PERLAPI(1) Perl Programmers Reference Guide PERLAPI(1)
NAME
perlapi - autogenerated documentation for the perl public API
DESCRIPTION
This file contains most of the documentation of the perl public API, as
generated by embed.pl. Specifically, it is a listing of functions,
macros, flags, and variables that may be used by extension writers.
Besides perlintern and config.h, some items are listed here as being
actually documented in another pod.
At the end is a list of functions which have yet to be documented.
Patches welcome! The interfaces of these are subject to change without
notice.
Some of the functions documented here are consolidated so that a single
entry serves for multiple functions which all do basically the same
thing, but have some slight differences. For example, one form might
process magic, while another doesn't. The name of each variation is
listed at the top of the single entry. But if all have the same
signature (arguments and return type) except for their names, only the
usage for the base form is shown. If any one of the forms has a
different signature (such as returning "const" or not) every function's
signature is explicitly displayed.
Anything not listed here or in the other mentioned pods is not part of
the public API, and should not be used by extension writers at all. For
these reasons, blindly using functions listed in proto.h is to be
avoided when writing extensions.
In Perl, unlike C, a string of characters may generally contain embedded
"NUL" characters. Sometimes in the documentation a Perl string is
referred to as a "buffer" to distinguish it from a C string, but
sometimes they are both just referred to as strings.
Note that all Perl API global variables must be referenced with the
"PL_" prefix. Again, those not listed here are not to be used by
extension writers, and may be changed or removed without notice; same
with macros. Some macros are provided for compatibility with the older,
unadorned names, but this support may be disabled in a future release.
Perl was originally written to handle US-ASCII only (that is characters
whose ordinal numbers are in the range 0 - 127). And documentation and
comments may still use the term ASCII, when sometimes in fact the entire
range from 0 - 255 is meant.
The non-ASCII characters below 256 can have various meanings, depending
on various things. (See, most notably, perllocale.) But usually the
whole range can be referred to as ISO-8859-1. Often, the term "Latin-1"
(or "Latin1") is used as an equivalent for ISO-8859-1. But some people
treat "Latin1" as referring just to the characters in the range 128
through 255, or sometimes from 160 through 255. This documentation uses
"Latin1" and "Latin-1" to refer to all 256 characters.
Note that Perl can be compiled and run under either ASCII or EBCDIC (See
perlebcdic). Most of the documentation (and even comments in the code)
ignore the EBCDIC possibility. For almost all purposes the differences
are transparent. As an example, under EBCDIC, instead of UTF-8, UTF-
EBCDIC is used to encode Unicode strings, and so whenever this
documentation refers to "utf8" (and variants of that name, including in
function names), it also (essentially transparently) means "UTF-EBCDIC".
But the ordinals of characters differ between ASCII, EBCDIC, and the
UTF- encodings, and a string encoded in UTF-EBCDIC may occupy a
different number of bytes than in UTF-8.
The organization of this document is tentative and subject to change.
Suggestions and patches welcome perl5-porters@perl.org
<mailto:perl5-porters@perl.org>.
The sections in this document currently are
"AV Handling"
"Callback Functions"
"Casting"
"Character case changing"
"Character classification"
"Compiler and Preprocessor information"
"Compiler directives"
"Compile-time scope hooks"
"Concurrency"
"COPs and Hint Hashes"
"Custom Operators"
"CV Handling"
"Debugging"
"Display functions"
"Embedding, Threads, and Interpreter Cloning"
"Errno"
"Exception Handling (simple) Macros"
"Filesystem configuration values"
"Floating point"
"General Configuration"
"Global Variables"
"GV Handling and Stashes"
"Hook manipulation"
"HV Handling"
"Input/Output"
"Integer"
"I/O Formats"
"Lexer interface"
"Locales"
"Magic"
"Memory Management"
"MRO"
"Multicall Functions"
"Numeric Functions"
"Optrees"
"Pack and Unpack"
"Pad Data Structures"
"Password and Group access"
"Paths to system commands"
"Prototype information"
"Reference-counted stack manipulation"
"REGEXP Functions"
"Reports and Formats"
"Signals"
"Site configuration"
"Sockets configuration values"
"Source Filters"
"Stack Manipulation Macros"
"String Handling"
"SV Flags"
"SV Handling"
"Tainting"
"Time"
"Typedef names"
"Unicode Support"
"Utility Functions"
"Versioning"
"Warning and Dieing"
"XS"
"Undocumented elements"
The listing below is alphabetical, case insensitive.
AV Handling
"AV"
Described in perlguts.
"AvALLOC"
Described in perlguts.
AvALLOC(AV* av)
"AvARRAY"
Returns a pointer to the AV's internal SV* array.
This is useful for doing pointer arithmetic on the array. If all
you need is to look up an array element, then prefer "av_fetch".
SV** AvARRAY(AV* av)
"av_clear"
Frees all the elements of an array, leaving it empty. The XS
equivalent of "@array = ()". See also "av_undef".
Note that it is possible that the actions of a destructor called
directly or indirectly by freeing an element of the array could
cause the reference count of the array itself to be reduced (e.g. by
deleting an entry in the symbol table). So it is a possibility that
the AV could have been freed (or even reallocated) on return from
the call unless you hold a reference to it.
void av_clear(AV *av)
"av_count"
Returns the number of elements in the array "av". This is the true
length of the array, including any undefined elements. It is always
the same as "av_top_index(av) + 1".
Size_t av_count(AV *av)
"av_create_and_push"
Push an SV onto the end of the array, creating the array if
necessary. A small internal helper function to remove a commonly
duplicated idiom.
NOTE: "av_create_and_push" must be explicitly called as
"Perl_av_create_and_push" with an "aTHX_" parameter.
void Perl_av_create_and_push(pTHX_ AV ** const avp,
SV * const val)
"av_create_and_unshift_one"
Unshifts an SV onto the beginning of the array, creating the array
if necessary. A small internal helper function to remove a commonly
duplicated idiom.
NOTE: "av_create_and_unshift_one" must be explicitly called as
"Perl_av_create_and_unshift_one" with an "aTHX_" parameter.
SV ** Perl_av_create_and_unshift_one(pTHX_ AV ** const avp,
SV * const val)
"av_delete"
Deletes the element indexed by "key" from the array, makes the
element mortal, and returns it. If "flags" equals "G_DISCARD", the
element is freed and NULL is returned. NULL is also returned if
"key" is out of range.
Perl equivalent: "splice(@myarray, $key, 1, undef)" (with the
"splice" in void context if "G_DISCARD" is present).
SV * av_delete(AV *av, SSize_t key, I32 flags)
"av_exists"
Returns true if the element indexed by "key" has been initialized.
This relies on the fact that uninitialized array elements are set to
"NULL".
Perl equivalent: exists($myarray[$key]).
bool av_exists(AV *av, SSize_t key)
"av_extend"
Pre-extend an array so that it is capable of storing values at
indexes "0..key". Thus "av_extend(av,99)" guarantees that the array
can store 100 elements, i.e. that "av_store(av, 0, sv)" through
"av_store(av, 99, sv)" on a plain array will work without any
further memory allocation.
If the av argument is a tied array then will call the "EXTEND" tied
array method with an argument of "(key+1)".
void av_extend(AV *av, SSize_t key)
"av_fetch"
Returns the SV at the specified index in the array. The "key" is
the index. If "lval" is true, you are guaranteed to get a real SV
back (in case it wasn't real before), which you can then modify.
Check that the return value is non-NULL before dereferencing it to a
"SV*".
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts
for more information on how to use this function on tied arrays.
The rough perl equivalent is $myarray[$key].
SV ** av_fetch(AV *av, SSize_t key, I32 lval)
"AvFILL"
Same as "av_top_index" or "av_tindex".
SSize_t AvFILL(AV* av)
"av_fill"
Set the highest index in the array to the given number, equivalent
to Perl's "$#array = $fill;".
The number of elements in the array will be "fill + 1" after
av_fill() returns. If the array was previously shorter, then the
additional elements appended are set to NULL. If the array was
longer, then the excess elements are freed. "av_fill(av, -1)" is
the same as av_clear(av).
void av_fill(AV *av, SSize_t fill)
"av_len"
Same as "av_top_index". Note that, unlike what the name implies, it
returns the maximum index in the array. This is unlike "sv_len",
which returns what you would expect.
To get the true number of elements in the array, instead use
"av_count".
SSize_t av_len(AV *av)
"av_make"
Creates a new AV and populates it with a list (**strp, length
"size") of SVs. A copy is made of each SV, so their refcounts are
not changed. The new AV will have a reference count of 1.
Perl equivalent: "my @new_array = ($scalar1, $scalar2,
$scalar3...);"
AV * av_make(SSize_t size, SV **strp)
"av_pop"
Removes one SV from the end of the array, reducing its size by one
and returning the SV (transferring control of one reference count)
to the caller. Returns &PL_sv_undef if the array is empty.
Perl equivalent: "pop(@myarray);"
SV * av_pop(AV *av)
"av_push"
Pushes an SV (transferring control of one reference count) onto the
end of the array. The array will grow automatically to accommodate
the addition.
Perl equivalent: "push @myarray, $val;".
void av_push(AV *av, SV *val)
"av_push_simple"
This is a cut-down version of av_push that assumes that the array is
very straightforward - no magic, not readonly, and AvREAL - and that
"key" is not less than -1. This function MUST NOT be used in
situations where any of those assumptions may not hold.
Pushes an SV (transferring control of one reference count) onto the
end of the array. The array will grow automatically to accommodate
the addition.
Perl equivalent: "push @myarray, $val;".
void av_push_simple(AV *av, SV *val)
"av_shift"
Removes one SV from the start of the array, reducing its size by one
and returning the SV (transferring control of one reference count)
to the caller. Returns &PL_sv_undef if the array is empty.
Perl equivalent: "shift(@myarray);"
SV * av_shift(AV *av)
"av_store"
Stores an SV in an array. The array index is specified as "key".
The return value will be "NULL" if the operation failed or if the
value did not need to be actually stored within the array (as in the
case of tied arrays). Otherwise, it can be dereferenced to get the
"SV*" that was stored there (= "val")).
Note that the caller is responsible for suitably incrementing the
reference count of "val" before the call, and decrementing it if the
function returned "NULL".
Approximate Perl equivalent: "splice(@myarray, $key, 1, $val)".
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts
for more information on how to use this function on tied arrays.
SV ** av_store(AV *av, SSize_t key, SV *val)
"av_tindex"
"av_top_index"
These behave identically. If the array "av" is empty, these return
-1; otherwise they return the maximum value of the indices of all
the array elements which are currently defined in "av".
They process 'get' magic.
The Perl equivalent for these is $#av.
Use "av_count" to get the number of elements in an array.
SSize_t av_tindex(AV *av)
"av_undef"
Undefines the array. The XS equivalent of undef(@array).
As well as freeing all the elements of the array (like av_clear()),
this also frees the memory used by the av to store its list of
scalars.
See "av_clear" for a note about the array possibly being invalid on
return.
void av_undef(AV *av)
"av_unshift"
Unshift the given number of "undef" values onto the beginning of the
array. The array will grow automatically to accommodate the
addition.
Perl equivalent: "unshift @myarray, ((undef) x $num);"
void av_unshift(AV *av, SSize_t num)
"get_av"
Returns the AV of the specified Perl global or package array with
the given name (so it won't work on lexical variables). "flags" are
passed to "gv_fetchpv". If "GV_ADD" is set and the Perl variable
does not exist then it will be created. If "flags" is zero
(ignoring "SVf_UTF8") and the variable does not exist then "NULL" is
returned.
Perl equivalent: "@{"$name"}".
NOTE: the perl_get_av() form is deprecated.
AV * get_av(const char *name, I32 flags)
"newAV"
"newAV_mortal"
"newAV_alloc_x"
"newAV_alloc_xz"
These all create a new AV, setting the reference count to 1. If you
also know the initial elements of the array with, see ""av_make"".
As background, an array consists of three things:
1. A data structure containing information about the array as a
whole, such as its size and reference count.
2. A C language array of pointers to the individual elements.
These are treated as pointers to SVs, so all must be castable to
SV*.
3. The individual elements themselves. These could be, for
instance, SVs and/or AVs and/or HVs, etc.
An empty array need only have the first data structure, and all
these functions create that. They differ in what else they do, as
follows:
"newAV" form
This does nothing beyond creating the whole-array data
structure. The Perl equivalent is approximately "my @array;"
This is useful when the minimum size of the array could be zero
(perhaps there are likely code paths that will entirely skip
using it).
If the array does get used, the pointers data structure will
need to be allocated at that time. This will end up being done
by "av_extend">, either explicitly:
av_extend(av, len);
or implicitly when the first element is stored:
(void)av_store(av, 0, sv);
Unused array elements are typically initialized by "av_extend".
"newAV_mortal" form
This also creates the whole-array data structure, but also
mortalises it. (That is to say, a reference to the AV is added
to the "temps" stack.)
"newAV_alloc_x" form
This effectively does a "newAV" followed by also allocating
(uninitialized) space for the pointers array. This is used when
you know ahead of time the likely minimum size of the array. It
is more efficient to do this than doing a plain "newAV" followed
by an "av_extend".
Of course the array can be extended later should it become
necessary.
"size" must be at least 1.
"newAV_alloc_xz" form
This is "newAV_alloc_x", but initializes each pointer in it to
NULL. This gives added safety to guard against them being read
before being set.
"size" must be at least 1.
The following examples all result in an array that can fit four
elements (indexes 0 .. 3):
AV *av = newAV();
av_extend(av, 3);
AV *av = newAV_alloc_x(4);
AV *av = newAV_alloc_xz(4);
In contrast, the following examples allocate an array that is only
guaranteed to fit one element without extending:
AV *av = newAV_alloc_x(1);
AV *av = newAV_alloc_xz(1);
AV * newAV ()
AV * newAV_mortal ()
AV * newAV_alloc_x (SSize_t size)
AV * newAV_alloc_xz(SSize_t size)
"newAVav"
Creates a new AV and populates it with values copied from an
existing AV. The new AV will have a reference count of 1, and will
contain newly created SVs copied from the original SV. The original
source will remain unchanged.
Perl equivalent: "my @new_array = @existing_array;"
AV * newAVav(AV *oav)
"newAVhv"
Creates a new AV and populates it with keys and values copied from
an existing HV. The new AV will have a reference count of 1, and
will contain newly created SVs copied from the original HV. The
original source will remain unchanged.
Perl equivalent: "my @new_array = %existing_hash;"
AV * newAVhv(HV *ohv)
"Nullav"
"DEPRECATED!" It is planned to remove "Nullav" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Null AV pointer.
(deprecated - use "(AV *)NULL" instead)
Callback Functions
"call_argv"
Performs a callback to the specified named and package-scoped Perl
subroutine with "argv" (a "NULL"-terminated array of strings) as
arguments. See perlcall.
Approximate Perl equivalent: "&{"$sub_name"}(@$argv)".
NOTE: the perl_call_argv() form is deprecated.
SSize_t call_argv(const char *sub_name, I32 flags, char **argv)
"call_method"
Performs a callback to the specified Perl method. The blessed
object must be on the stack. See perlcall.
NOTE: the perl_call_method() form is deprecated.
SSize_t call_method(const char *methname, I32 flags)
"call_pv"
Performs a callback to the specified Perl sub. See perlcall.
NOTE: the perl_call_pv() form is deprecated.
SSize_t call_pv(const char *sub_name, I32 flags)
"call_sv"
Performs a callback to the Perl sub specified by the SV.
If neither the "G_METHOD" nor "G_METHOD_NAMED" flag is supplied, the
SV may be any of a CV, a GV, a reference to a CV, a reference to a
GV or SvPV(sv) will be used as the name of the sub to call.
If the "G_METHOD" flag is supplied, the SV may be a reference to a
CV or SvPV(sv) will be used as the name of the method to call.
If the "G_METHOD_NAMED" flag is supplied, SvPV(sv) will be used as
the name of the method to call.
Some other values are treated specially for internal use and should
not be depended on.
See perlcall.
NOTE: the perl_call_sv() form is deprecated.
SSize_t call_sv(SV *sv, I32 flags)
"DESTRUCTORFUNC_NOCONTEXT_t"
Described in perlguts.
"DESTRUCTORFUNC_t"
Described in perlguts.
"ENTER"
Opening bracket on a callback. See "LEAVE" and perlcall.
ENTER;
"ENTER_with_name"
Same as "ENTER", but when debugging is enabled it also associates
the given literal string with the new scope.
ENTER_with_name("name");
"eval_pv"
Tells Perl to "eval" the given string in scalar context and return
an SV* result.
NOTE: the perl_eval_pv() form is deprecated.
SV * eval_pv(const char *p, I32 croak_on_error)
"eval_sv"
Tells Perl to "eval" the string in the SV. It supports the same
flags as "call_sv", with the obvious exception of "G_EVAL". See
perlcall.
The "G_RETHROW" flag can be used if you only need eval_sv() to
execute code specified by a string, but not catch any errors.
By default the code is compiled and executed with the default hints,
such as strict and features. Set "G_USEHINTS" in flags to use the
current hints from "PL_curcop".
NOTE: the perl_eval_sv() form is deprecated.
SSize_t eval_sv(SV *sv, I32 flags)
"FREETMPS"
Closing bracket for temporaries on a callback. See "SAVETMPS" and
perlcall.
FREETMPS;
"G_DISCARD"
Described in perlcall.
"G_EVAL"
Described in perlcall.
"GIMME"
"DEPRECATED!" It is planned to remove "GIMME" from a future release
of Perl. Do not use it for new code; remove it from existing code.
A backward-compatible version of "GIMME_V" which can only return
"G_SCALAR" or "G_LIST"; in a void context, it returns "G_SCALAR".
Deprecated. Use "GIMME_V" instead.
U32 GIMME
"GIMME_V"
The XSUB-writer's equivalent to Perl's "wantarray". Returns
"G_VOID", "G_SCALAR" or "G_LIST" for void, scalar or list context,
respectively. See perlcall for a usage example.
U32 GIMME_V
"G_KEEPERR"
Described in perlcall.
"G_LIST"
Described in perlcall.
"G_NOARGS"
Described in perlcall.
"G_SCALAR"
Described in perlcall.
"G_VOID"
Described in perlcall.
"is_lvalue_sub"
Returns non-zero if the sub calling this function is being called in
an lvalue context. Returns 0 otherwise.
I32 is_lvalue_sub()
"LEAVE"
Closing bracket on a callback. See "ENTER" and perlcall.
LEAVE;
"LEAVE_with_name"
Same as "LEAVE", but when debugging is enabled it first checks that
the scope has the given name. "name" must be a literal string.
LEAVE_with_name("name");
"MORTALDESTRUCTOR_SV"
Described in perlguts.
MORTALDESTRUCTOR_SV(SV *coderef, SV *args)
"mortal_destructor_sv"
This function arranges for either a Perl code reference, or a C
function reference to be called at the end of the current statement.
The "coderef" argument determines the type of function that will be
called. If it is SvROK() it is assumed to be a reference to a CV and
will arrange for the coderef to be called. If it is not SvROK() then
it is assumed to be a SvIV() which is SvIOK() whose value is a
pointer to a C function of type "DESTRUCTORFUNC_t" created using
PTR2INT(). Either way the "args" parameter will be provided to the
callback as a parameter, although the rules for doing so differ
between the Perl and C mode. Normally this function is only used
directly for the Perl case and the wrapper mortal_destructor_x() is
used for the C function case.
When operating in Perl callback mode the "args" parameter may be
NULL in which case the code reference is called with no arguments,
otherwise if it is an AV (SvTYPE(args) == SVt_PVAV) then the
contents of the AV will be used as the arguments to the code
reference, and if it is any other type then the "args" SV will be
provided as a single argument to the code reference.
When operating in a C callback mode the "args" parameter will be
passed directly to the C function as a "void *" pointer. No
additional processing of the argument will be peformed, and it is
the callers responsibility to free the "args" parameter if
necessary.
Be aware that there is a signficant difference in timing between the
end of the current statement and the end of the current pseudo
block. If you are looking for a mechanism to trigger a function at
the end of the current pseudo block you should look at
""SAVEDESTRUCTOR_X"" in perlapi instead of this function.
void mortal_destructor_sv(SV *coderef, SV *args)
"MORTALSVFUNC_X"
Described in perlguts.
MORTALSVFUNC_X(SVFUNC_t f, SV *sv)
"PL_errgv"
Described in perlcall.
"save_aelem"
"save_aelem_flags"
These each arrange for the value of the array element "av[idx]" to
be restored at the end of the enclosing pseudo-block.
In "save_aelem", the SV at C**sptr> will be replaced by a new
"undef" scalar. That scalar will inherit any magic from the
original **sptr, and any 'set' magic will be processed.
In "save_aelem_flags", "SAVEf_KEEPOLDELEM" being set in "flags"
causes the function to forgo all that: the scalar at **sptr is
untouched. If "SAVEf_KEEPOLDELEM" is not set, the SV at C**sptr>
will be replaced by a new "undef" scalar. That scalar will inherit
any magic from the original **sptr. Any 'set' magic will be
processed if and only if "SAVEf_SETMAGIC" is set in in "flags".
void save_aelem (AV *av, SSize_t idx, SV **sptr)
void save_aelem_flags(AV *av, SSize_t idx, SV **sptr,
const U32 flags)
"save_aptr"
Described in perlguts.
void save_aptr(AV **aptr)
"save_ary"
Described in perlguts.
AV * save_ary(GV *gv)
"SAVEBOOL"
Described in perlguts.
SAVEBOOL(bool i)
"SAVEDELETE"
Described in perlguts.
SAVEDELETE(HV * hv, char * key, I32 length)
"SAVEDESTRUCTOR"
Described in perlguts.
SAVEDESTRUCTOR(DESTRUCTORFUNC_NOCONTEXT_t f, void *p)
"SAVEDESTRUCTOR_X"
Described in perlguts.
SAVEDESTRUCTOR_X(DESTRUCTORFUNC_t f, void *p)
"SAVEFREEOP"
Described in perlguts.
SAVEFREEOP(OP *op)
"SAVEFREEPV"
Described in perlguts.
SAVEFREEPV(char *pv)
"SAVEFREERCPV"
Described in perlguts.
SAVEFREERCPV(char *pv)
"SAVEFREESV"
Described in perlguts.
SAVEFREESV(SV* sv)
"SAVEGENERICSV"
Described in perlguts.
SAVEGENERICSV(char **psv)
"save_hash"
Described in perlguts.
HV * save_hash(GV *gv)
"save_helem"
"save_helem_flags"
These each arrange for the value of the hash element (in Perlish
terms) "$hv{key}]" to be restored at the end of the enclosing
pseudo-block.
In "save_helem", the SV at C**sptr> will be replaced by a new
"undef" scalar. That scalar will inherit any magic from the
original **sptr, and any 'set' magic will be processed.
In "save_helem_flags", "SAVEf_KEEPOLDELEM" being set in "flags"
causes the function to forgo all that: the scalar at **sptr is
untouched. If "SAVEf_KEEPOLDELEM" is not set, the SV at C**sptr>
will be replaced by a new "undef" scalar. That scalar will inherit
any magic from the original **sptr. Any 'set' magic will be
processed if and only if "SAVEf_SETMAGIC" is set in in "flags".
void save_helem (HV *hv, SV *key, SV **sptr)
void save_helem_flags(HV *hv, SV *key, SV **sptr,
const U32 flags)
"save_hptr"
Described in perlguts.
void save_hptr(HV **hptr)
"SAVEINT"
Described in perlguts.
SAVEINT(int i)
"save_item"
Described in perlguts.
void save_item(SV *item)
"SAVEIV"
Described in perlguts.
SAVEIV(IV i)
"SAVEI8"
Described in perlguts.
SAVEI8(I8 i)
"SAVEI16"
Described in perlguts.
SAVEI16(I16 i)
"SAVEI32"
Described in perlguts.
SAVEI32(I32 i)
"SAVELONG"
Described in perlguts.
SAVELONG(long i)
"SAVEMORTALIZESV"
Described in perlguts.
SAVEMORTALIZESV(SV* sv)
"SAVEPPTR"
Described in perlguts.
SAVEPPTR(char * p)
"SAVERCPV"
Described in perlguts.
SAVERCPV(char *pv)
"save_scalar"
Described in perlguts.
SV * save_scalar(GV *gv)
"SAVESPTR"
Described in perlguts.
SAVESPTR(SV * s)
"SAVESTACK_POS"
Described in perlguts.
SAVESTACK_POS()
"SAVESTRLEN"
Described in perlguts.
SAVESTRLEN(STRLEN i)
"save_svref"
Described in perlguts.
SV * save_svref(SV **sptr)
"SAVETMPS"
Opening bracket for temporaries on a callback. See "FREETMPS" and
perlcall.
SAVETMPS;
Casting
"Atof"
This is a synonym for ""my_atof"".
NV Atof(NN const char * const s)
"cBOOL"
Cast-to-bool. When Perl was able to be compiled on pre-C99
compilers, a "(bool)" cast didn't necessarily do the right thing, so
this macro was created (and made somewhat complicated to work around
bugs in old compilers). Now, many years later, and C99 is used,
this is no longer required, but is kept for backwards compatibility.
bool cBOOL(bool expr)
"INT2PTR"
Described in perlguts.
type INT2PTR(type, int value)
"I_V"
Cast an NV to IV while avoiding undefined C behavior
IV I_V(NV what)
"I_32"
Cast an NV to I32 while avoiding undefined C behavior
I32 I_32(NV what)
"PTR2IV"
Described in perlguts.
IV PTR2IV(void * ptr)
"PTR2nat"
Described in perlguts.
IV PTR2nat(void *)
"PTR2NV"
Described in perlguts.
NV PTR2NV(void * ptr)
"PTR2ul"
Described in perlguts.
unsigned long PTR2ul(void *)
"PTR2UV"
Described in perlguts.
UV PTR2UV(void * ptr)
"PTRV"
Described in perlguts.
"U_V"
Cast an NV to UV while avoiding undefined C behavior
UV U_V(NV what)
"U_32"
Cast an NV to U32 while avoiding undefined C behavior
U32 U_32(NV what)
Character case changing
Perl uses "full" Unicode case mappings. This means that converting a
single character to another case may result in a sequence of more than
one character. For example, the uppercase of "ß" (LATIN SMALL LETTER
SHARP S) is the two character sequence "SS". This presents some
complications The lowercase of all characters in the range 0..255 is a
single character, and thus "toLOWER_L1" is furnished. But, "toUPPER_L1"
can't exist, as it couldn't return a valid result for all legal inputs.
Instead "toUPPER_uvchr" has an API that does allow every possible legal
result to be returned.) Likewise no other function that is crippled by
not being able to give the correct results for the full range of
possible inputs has been implemented here.
"toFOLD"
"toFOLD_A"
"toFOLD_utf8"
"toFOLD_utf8_safe"
"toFOLD_uvchr"
These all return the foldcase of a character. "foldcase" is an
internal case for "/i" pattern matching. If the foldcase of
character A and the foldcase of character B are the same, they match
caselessly; otherwise they don't.
The differences in the forms are what domain they operate on, and
whether the input is specified as a code point (those forms with a
"cp" parameter) or as a UTF-8 string (the others). In the latter
case, the code point to use is the first one in the buffer of UTF-8
encoded code points, delineated by the arguments "p .. e - 1".
"toFOLD" and "toFOLD_A" are synonyms of each other. They return the
foldcase of any ASCII-range code point. In this range, the foldcase
is identical to the lowercase. All other inputs are returned
unchanged. Since these are macros, the input type may be any
integral one, and the output will occupy the same number of bits as
the input.
There is no "toFOLD_L1" nor "toFOLD_LATIN1" as the foldcase of some
code points in the 0..255 range is above that range or consists of
multiple characters. Instead use "toFOLD_uvchr".
"toFOLD_uvchr" returns the foldcase of any Unicode code point. The
return value is identical to that of "toFOLD_A" for input code
points in the ASCII range. The foldcase of the vast majority of
Unicode code points is the same as the code point itself. For
these, and for code points above the legal Unicode maximum, this
returns the input code point unchanged. It additionally stores the
UTF-8 of the result into the buffer beginning at "s", and its length
in bytes into *lenp. The caller must have made "s" large enough to
contain at least "UTF8_MAXBYTES_CASE+1" bytes to avoid possible
overflow.
NOTE: the foldcase of a code point may be more than one code point.
The return value of this function is only the first of these. The
entire foldcase is returned in "s". To determine if the result is
more than a single code point, you can do something like this:
uc = toFOLD_uvchr(cp, s, &len);
if (len > UTF8SKIP(s)) { is multiple code points }
else { is a single code point }
"toFOLD_utf8" and "toFOLD_utf8_safe" are synonyms of each other.
The only difference between these and "toFOLD_uvchr" is that the
source for these is encoded in UTF-8, instead of being a code point.
It is passed as a buffer starting at "p", with "e" pointing to one
byte beyond its end. The "p" buffer may certainly contain more than
one code point; but only the first one (up through "e - 1") is
examined. If the UTF-8 for the input character is malformed in some
way, the program may croak, or the function may return the
REPLACEMENT CHARACTER, at the discretion of the implementation, and
subject to change in future releases.
UV toFOLD (UV cp)
UV toFOLD_A (UV cp)
UV toFOLD_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)
UV toFOLD_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
UV toFOLD_uvchr (UV cp, U8* s, STRLEN* lenp)
"toLOWER"
"toLOWER_A"
"toLOWER_LATIN1"
"toLOWER_LC"
"toLOWER_L1"
"toLOWER_utf8"
"toLOWER_utf8_safe"
"toLOWER_uvchr"
These all return the lowercase of a character. The differences are
what domain they operate on, and whether the input is specified as a
code point (those forms with a "cp" parameter) or as a UTF-8 string
(the others). In the latter case, the code point to use is the
first one in the buffer of UTF-8 encoded code points, delineated by
the arguments "p .. e - 1".
"toLOWER" and "toLOWER_A" are synonyms of each other. They return
the lowercase of any uppercase ASCII-range code point. All other
inputs are returned unchanged. Since these are macros, the input
type may be any integral one, and the output will occupy the same
number of bits as the input.
"toLOWER_L1" and "toLOWER_LATIN1" are synonyms of each other. They
behave identically as "toLOWER" for ASCII-range input. But
additionally will return the lowercase of any uppercase code point
in the entire 0..255 range, assuming a Latin-1 encoding (or the
EBCDIC equivalent on such platforms).
"toLOWER_LC" returns the lowercase of the input code point according
to the rules of the current POSIX locale. Input code points outside
the range 0..255 are returned unchanged.
"toLOWER_uvchr" returns the lowercase of any Unicode code point.
The return value is identical to that of "toLOWER_L1" for input code
points in the 0..255 range. The lowercase of the vast majority of
Unicode code points is the same as the code point itself. For
these, and for code points above the legal Unicode maximum, this
returns the input code point unchanged. It additionally stores the
UTF-8 of the result into the buffer beginning at "s", and its length
in bytes into *lenp. The caller must have made "s" large enough to
contain at least "UTF8_MAXBYTES_CASE+1" bytes to avoid possible
overflow.
NOTE: the lowercase of a code point may be more than one code point.
The return value of this function is only the first of these. The
entire lowercase is returned in "s". To determine if the result is
more than a single code point, you can do something like this:
uc = toLOWER_uvchr(cp, s, &len);
if (len > UTF8SKIP(s)) { is multiple code points }
else { is a single code point }
"toLOWER_utf8" and "toLOWER_utf8_safe" are synonyms of each other.
The only difference between these and "toLOWER_uvchr" is that the
source for these is encoded in UTF-8, instead of being a code point.
It is passed as a buffer starting at "p", with "e" pointing to one
byte beyond its end. The "p" buffer may certainly contain more than
one code point; but only the first one (up through "e - 1") is
examined. If the UTF-8 for the input character is malformed in some
way, the program may croak, or the function may return the
REPLACEMENT CHARACTER, at the discretion of the implementation, and
subject to change in future releases.
UV toLOWER (UV cp)
UV toLOWER_A (UV cp)
UV toLOWER_LATIN1 (UV cp)
UV toLOWER_LC (UV cp)
UV toLOWER_L1 (UV cp)
UV toLOWER_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)
UV toLOWER_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
UV toLOWER_uvchr (UV cp, U8* s, STRLEN* lenp)
"toTITLE"
"toTITLE_A"
"toTITLE_utf8"
"toTITLE_utf8_safe"
"toTITLE_uvchr"
These all return the titlecase of a character. The differences are
what domain they operate on, and whether the input is specified as a
code point (those forms with a "cp" parameter) or as a UTF-8 string
(the others). In the latter case, the code point to use is the
first one in the buffer of UTF-8 encoded code points, delineated by
the arguments "p .. e - 1".
"toTITLE" and "toTITLE_A" are synonyms of each other. They return
the titlecase of any lowercase ASCII-range code point. In this
range, the titlecase is identical to the uppercase. All other
inputs are returned unchanged. Since these are macros, the input
type may be any integral one, and the output will occupy the same
number of bits as the input.
There is no "toTITLE_L1" nor "toTITLE_LATIN1" as the titlecase of
some code points in the 0..255 range is above that range or consists
of multiple characters. Instead use "toTITLE_uvchr".
"toTITLE_uvchr" returns the titlecase of any Unicode code point.
The return value is identical to that of "toTITLE_A" for input code
points in the ASCII range. The titlecase of the vast majority of
Unicode code points is the same as the code point itself. For
these, and for code points above the legal Unicode maximum, this
returns the input code point unchanged. It additionally stores the
UTF-8 of the result into the buffer beginning at "s", and its length
in bytes into *lenp. The caller must have made "s" large enough to
contain at least "UTF8_MAXBYTES_CASE+1" bytes to avoid possible
overflow.
NOTE: the titlecase of a code point may be more than one code point.
The return value of this function is only the first of these. The
entire titlecase is returned in "s". To determine if the result is
more than a single code point, you can do something like this:
uc = toTITLE_uvchr(cp, s, &len);
if (len > UTF8SKIP(s)) { is multiple code points }
else { is a single code point }
"toTITLE_utf8" and "toTITLE_utf8_safe" are synonyms of each other.
The only difference between these and "toTITLE_uvchr" is that the
source for these is encoded in UTF-8, instead of being a code point.
It is passed as a buffer starting at "p", with "e" pointing to one
byte beyond its end. The "p" buffer may certainly contain more than
one code point; but only the first one (up through "e - 1") is
examined. If the UTF-8 for the input character is malformed in some
way, the program may croak, or the function may return the
REPLACEMENT CHARACTER, at the discretion of the implementation, and
subject to change in future releases.
UV toTITLE (UV cp)
UV toTITLE_A (UV cp)
UV toTITLE_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)
UV toTITLE_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
UV toTITLE_uvchr (UV cp, U8* s, STRLEN* lenp)
"toUPPER"
"toUPPER_A"
"toUPPER_utf8"
"toUPPER_utf8_safe"
"toUPPER_uvchr"
These all return the uppercase of a character. The differences are
what domain they operate on, and whether the input is specified as a
code point (those forms with a "cp" parameter) or as a UTF-8 string
(the others). In the latter case, the code point to use is the
first one in the buffer of UTF-8 encoded code points, delineated by
the arguments "p .. e - 1".
"toUPPER" and "toUPPER_A" are synonyms of each other. They return
the uppercase of any lowercase ASCII-range code point. All other
inputs are returned unchanged. Since these are macros, the input
type may be any integral one, and the output will occupy the same
number of bits as the input.
There is no "toUPPER_L1" nor "toUPPER_LATIN1" as the uppercase of
some code points in the 0..255 range is above that range or consists
of multiple characters. Instead use "toUPPER_uvchr".
"toUPPER_uvchr" returns the uppercase of any Unicode code point.
The return value is identical to that of "toUPPER_A" for input code
points in the ASCII range. The uppercase of the vast majority of
Unicode code points is the same as the code point itself. For
these, and for code points above the legal Unicode maximum, this
returns the input code point unchanged. It additionally stores the
UTF-8 of the result into the buffer beginning at "s", and its length
in bytes into *lenp. The caller must have made "s" large enough to
contain at least "UTF8_MAXBYTES_CASE+1" bytes to avoid possible
overflow.
NOTE: the uppercase of a code point may be more than one code point.
The return value of this function is only the first of these. The
entire uppercase is returned in "s". To determine if the result is
more than a single code point, you can do something like this:
uc = toUPPER_uvchr(cp, s, &len);
if (len > UTF8SKIP(s)) { is multiple code points }
else { is a single code point }
"toUPPER_utf8" and "toUPPER_utf8_safe" are synonyms of each other.
The only difference between these and "toUPPER_uvchr" is that the
source for these is encoded in UTF-8, instead of being a code point.
It is passed as a buffer starting at "p", with "e" pointing to one
byte beyond its end. The "p" buffer may certainly contain more than
one code point; but only the first one (up through "e - 1") is
examined. If the UTF-8 for the input character is malformed in some
way, the program may croak, or the function may return the
REPLACEMENT CHARACTER, at the discretion of the implementation, and
subject to change in future releases.
UV toUPPER (UV cp)
UV toUPPER_A (UV cp)
UV toUPPER_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp)
UV toUPPER_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
UV toUPPER_uvchr (UV cp, U8* s, STRLEN* lenp)
Character classification
This section is about functions (really macros) that classify characters
into types, such as punctuation versus alphabetic, etc. Most of these
are analogous to regular expression character classes. (See "POSIX
Character Classes" in perlrecharclass.) There are several variants for
each class. (Not all macros have all variants; each item below lists
the ones valid for it.) None are affected by "use bytes", and only the
ones with "LC" in the name are affected by the current locale.
The base function, e.g., isALPHA(), takes any signed or unsigned value,
treating it as a code point, and returns a boolean as to whether or not
the character represented by it is (or on non-ASCII platforms,
corresponds to) an ASCII character in the named class based on platform,
Unicode, and Perl rules. If the input is a number that doesn't fit in
an octet, FALSE is returned.
Variant "isFOO_A" (e.g., isALPHA_A()) is identical to the base function
with no suffix "_A". This variant is used to emphasize by its name that
only ASCII-range characters can return TRUE.
Variant "isFOO_L1" imposes the Latin-1 (or EBCDIC equivalent) character
set onto the platform. That is, the code points that are ASCII are
unaffected, since ASCII is a subset of Latin-1. But the non-ASCII code
points are treated as if they are Latin-1 characters. For example,
isWORDCHAR_L1() will return true when called with the code point 0xDF,
which is a word character in both ASCII and EBCDIC (though it represents
different characters in each). If the input is a number that doesn't
fit in an octet, FALSE is returned. (Perl's documentation uses a
colloquial definition of Latin-1, to include all code points below 256.)
Variant "isFOO_uvchr" is exactly like the "isFOO_L1" variant, for inputs
below 256, but if the code point is larger than 255, Unicode rules are
used to determine if it is in the character class. For example,
isWORDCHAR_uvchr(0x100) returns TRUE, since 0x100 is LATIN CAPITAL
LETTER A WITH MACRON in Unicode, and is a word character.
Variants "isFOO_utf8" and "isFOO_utf8_safe" are like "isFOO_uvchr", but
are used for UTF-8 encoded strings. The two forms are different names
for the same thing. Each call to one of these classifies the first
character of the string starting at "p". The second parameter, "e",
points to anywhere in the string beyond the first character, up to one
byte past the end of the entire string. Although both variants are
identical, the suffix "_safe" in one name emphasizes that it will not
attempt to read beyond "e - 1", provided that the constraint "s < e" is
true (this is asserted for in "-DDEBUGGING" builds). If the UTF-8 for
the input character is malformed in some way, the program may croak, or
the function may return FALSE, at the discretion of the implementation,
and subject to change in future releases.
Variant "isFOO_LC" is like the "isFOO_A" and "isFOO_L1" variants, but
the result is based on the current locale, which is what "LC" in the
name stands for. If Perl can determine that the current locale is a
UTF-8 locale, it uses the published Unicode rules; otherwise, it uses
the C library function that gives the named classification. For
example, isDIGIT_LC() when not in a UTF-8 locale returns the result of
calling isdigit(). FALSE is always returned if the input won't fit into
an octet. On some platforms where the C library function is known to be
defective, Perl changes its result to follow the POSIX standard's rules.
Variant "isFOO_LC_uvchr" acts exactly like "isFOO_LC" for inputs less
than 256, but for larger ones it returns the Unicode classification of
the code point.
Variants "isFOO_LC_utf8" and "isFOO_LC_utf8_safe" are like
"isFOO_LC_uvchr", but are used for UTF-8 encoded strings. The two forms
are different names for the same thing. Each call to one of these
classifies the first character of the string starting at "p". The
second parameter, "e", points to anywhere in the string beyond the first
character, up to one byte past the end of the entire string. Although
both variants are identical, the suffix "_safe" in one name emphasizes
that it will not attempt to read beyond "e - 1", provided that the
constraint "s < e" is true (this is asserted for in "-DDEBUGGING"
builds). If the UTF-8 for the input character is malformed in some way,
the program may croak, or the function may return FALSE, at the
discretion of the implementation, and subject to change in future
releases.
"isALNUM"
"isALNUM_A"
"isALNUM_LC"
"isALNUM_LC_uvchr"
These are each a synonym for their respectively named ""isWORDCHAR""
variant.
They are provided for backward compatibility, even though a word
character includes more than the standard C language meaning of
alphanumeric. To get the C language definition, use the
corresponding ""isALPHANUMERIC"" variant.
bool isALNUM(UV ch)
"isALNUMC"
"isALNUMC_A"
"isALNUMC_LC"
"isALNUMC_LC_uvchr"
"isALNUMC_L1"
These are discouraged, backward compatibility macros for
""isALPHANUMERIC"". That is, each returns a boolean indicating
whether the specified character is one of "[A-Za-z0-9]", analogous
to "m/[[:alnum:]]/".
The "C" suffix in the names was meant to indicate that they
correspond to the C language isalnum(3).
bool isALNUMC(UV ch)
"isALPHA"
"isALPHA_A"
"isALPHA_LC"
"isALPHA_LC_utf8_safe"
"isALPHA_LC_uvchr"
"isALPHA_L1"
"isALPHA_utf8"
"isALPHA_utf8_safe"
"isALPHA_uvchr"
Returns a boolean indicating whether the specified input is one of
"[A-Za-z]", analogous to "m/[[:alpha:]]/". See the top of this
section for an explanation of the variants.
bool isALPHA (UV ch)
bool isALPHA_A (UV ch)
bool isALPHA_LC (UV ch)
bool isALPHA_LC_utf8_safe(U8 * s, U8 *end)
bool isALPHA_LC_uvchr (UV ch)
bool isALPHA_L1 (UV ch)
bool isALPHA_utf8 (U8 * s, U8 * end)
bool isALPHA_utf8_safe (U8 * s, U8 * end)
bool isALPHA_uvchr (UV ch)
"isALPHANUMERIC"
"isALPHANUMERIC_A"
"isALPHANUMERIC_LC"
"isALPHANUMERIC_LC_utf8_safe"
"isALPHANUMERIC_LC_uvchr"
"isALPHANUMERIC_L1"
"isALPHANUMERIC_utf8"
"isALPHANUMERIC_utf8_safe"
"isALPHANUMERIC_uvchr"
Returns a boolean indicating whether the specified character is one
of "[A-Za-z0-9]", analogous to "m/[[:alnum:]]/". See the top of
this section for an explanation of the variants.
bool isALPHANUMERIC (UV ch)
bool isALPHANUMERIC_A (UV ch)
bool isALPHANUMERIC_LC (UV ch)
bool isALPHANUMERIC_LC_utf8_safe(U8 * s, U8 *end)
bool isALPHANUMERIC_LC_uvchr (UV ch)
bool isALPHANUMERIC_L1 (UV ch)
bool isALPHANUMERIC_utf8 (U8 * s, U8 * end)
bool isALPHANUMERIC_utf8_safe (U8 * s, U8 * end)
bool isALPHANUMERIC_uvchr (UV ch)
"isASCII"
"isASCII_A"
"isASCII_LC"
"isASCII_LC_utf8_safe"
"isASCII_LC_uvchr"
"isASCII_L1"
"isASCII_utf8"
"isASCII_utf8_safe"
"isASCII_uvchr"
Returns a boolean indicating whether the specified character is one
of the 128 characters in the ASCII character set, analogous to
"m/[[:ascii:]]/". On non-ASCII platforms, it returns TRUE iff this
character corresponds to an ASCII character. Variants isASCII_A()
and isASCII_L1() are identical to isASCII(). See the top of this
section for an explanation of the variants. Note, however, that
some platforms do not have the C library routine isascii(). In
these cases, the variants whose names contain "LC" are the same as
the corresponding ones without.
Also note, that because all ASCII characters are UTF-8 invariant
(meaning they have the exact same representation (always a single
byte) whether encoded in UTF-8 or not), "isASCII" will give the
correct results when called with any byte in any string encoded or
not in UTF-8. And similarly "isASCII_utf8" and "isASCII_utf8_safe"
will work properly on any string encoded or not in UTF-8.
bool isASCII (UV ch)
bool isASCII_A (UV ch)
bool isASCII_LC (UV ch)
bool isASCII_LC_utf8_safe(U8 * s, U8 *end)
bool isASCII_LC_uvchr (UV ch)
bool isASCII_L1 (UV ch)
bool isASCII_utf8 (U8 * s, U8 * end)
bool isASCII_utf8_safe (U8 * s, U8 * end)
bool isASCII_uvchr (UV ch)
"isBLANK"
"isBLANK_A"
"isBLANK_LC"
"isBLANK_LC_utf8_safe"
"isBLANK_LC_uvchr"
"isBLANK_L1"
"isBLANK_utf8"
"isBLANK_utf8_safe"
"isBLANK_uvchr"
Returns a boolean indicating whether the specified character is a
character considered to be a blank, analogous to "m/[[:blank:]]/".
See the top of this section for an explanation of the variants.
Note, however, that some platforms do not have the C library routine
isblank(). In these cases, the variants whose names contain "LC"
are the same as the corresponding ones without.
bool isBLANK (UV ch)
bool isBLANK_A (UV ch)
bool isBLANK_LC (UV ch)
bool isBLANK_LC_utf8_safe(U8 * s, U8 *end)
bool isBLANK_LC_uvchr (UV ch)
bool isBLANK_L1 (UV ch)
bool isBLANK_utf8 (U8 * s, U8 * end)
bool isBLANK_utf8_safe (U8 * s, U8 * end)
bool isBLANK_uvchr (UV ch)
"isCNTRL"
"isCNTRL_A"
"isCNTRL_LC"
"isCNTRL_LC_utf8_safe"
"isCNTRL_LC_uvchr"
"isCNTRL_L1"
"isCNTRL_utf8"
"isCNTRL_utf8_safe"
"isCNTRL_uvchr"
Returns a boolean indicating whether the specified character is a
control character, analogous to "m/[[:cntrl:]]/". See the top of
this section for an explanation of the variants. On EBCDIC
platforms, you almost always want to use the "isCNTRL_L1" variant.
bool isCNTRL (UV ch)
bool isCNTRL_A (UV ch)
bool isCNTRL_LC (UV ch)
bool isCNTRL_LC_utf8_safe(U8 * s, U8 *end)
bool isCNTRL_LC_uvchr (UV ch)
bool isCNTRL_L1 (UV ch)
bool isCNTRL_utf8 (U8 * s, U8 * end)
bool isCNTRL_utf8_safe (U8 * s, U8 * end)
bool isCNTRL_uvchr (UV ch)
"isDIGIT"
"isDIGIT_A"
"isDIGIT_LC"
"isDIGIT_LC_utf8_safe"
"isDIGIT_LC_uvchr"
"isDIGIT_L1"
"isDIGIT_utf8"
"isDIGIT_utf8_safe"
"isDIGIT_uvchr"
Returns a boolean indicating whether the specified character is a
digit, analogous to "m/[[:digit:]]/". Variants "isDIGIT_A" and
"isDIGIT_L1" are identical to "isDIGIT". See the top of this
section for an explanation of the variants.
bool isDIGIT (UV ch)
bool isDIGIT_A (UV ch)
bool isDIGIT_LC (UV ch)
bool isDIGIT_LC_utf8_safe(U8 * s, U8 *end)
bool isDIGIT_LC_uvchr (UV ch)
bool isDIGIT_L1 (UV ch)
bool isDIGIT_utf8 (U8 * s, U8 * end)
bool isDIGIT_utf8_safe (U8 * s, U8 * end)
bool isDIGIT_uvchr (UV ch)
"isGRAPH"
"isGRAPH_A"
"isGRAPH_LC"
"isGRAPH_LC_utf8_safe"
"isGRAPH_LC_uvchr"
"isGRAPH_L1"
"isGRAPH_utf8"
"isGRAPH_utf8_safe"
"isGRAPH_uvchr"
Returns a boolean indicating whether the specified character is a
graphic character, analogous to "m/[[:graph:]]/". See the top of
this section for an explanation of the variants.
bool isGRAPH (UV ch)
bool isGRAPH_A (UV ch)
bool isGRAPH_LC (UV ch)
bool isGRAPH_LC_utf8_safe(U8 * s, U8 *end)
bool isGRAPH_LC_uvchr (UV ch)
bool isGRAPH_L1 (UV ch)
bool isGRAPH_utf8 (U8 * s, U8 * end)
bool isGRAPH_utf8_safe (U8 * s, U8 * end)
bool isGRAPH_uvchr (UV ch)
"isIDCONT"
"isIDCONT_A"
"isIDCONT_LC"
"isIDCONT_LC_utf8_safe"
"isIDCONT_LC_uvchr"
"isIDCONT_L1"
"isIDCONT_utf8"
"isIDCONT_utf8_safe"
"isIDCONT_uvchr"
Returns a boolean indicating whether the specified character can be
the second or succeeding character of an identifier. This is very
close to, but not quite the same as the official Unicode property
"XID_Continue". The difference is that this returns true only if
the input character also matches "isWORDCHAR". See the top of this
section for an explanation of the variants.
bool isIDCONT (UV ch)
bool isIDCONT_A (UV ch)
bool isIDCONT_LC (UV ch)
bool isIDCONT_LC_utf8_safe(U8 * s, U8 *end)
bool isIDCONT_LC_uvchr (UV ch)
bool isIDCONT_L1 (UV ch)
bool isIDCONT_utf8 (U8 * s, U8 * end)
bool isIDCONT_utf8_safe (U8 * s, U8 * end)
bool isIDCONT_uvchr (UV ch)
"isIDFIRST"
"isIDFIRST_A"
"isIDFIRST_LC"
"isIDFIRST_LC_utf8_safe"
"isIDFIRST_LC_uvchr"
"isIDFIRST_L1"
"isIDFIRST_utf8"
"isIDFIRST_utf8_safe"
"isIDFIRST_uvchr"
Returns a boolean indicating whether the specified character can be
the first character of an identifier. This is very close to, but
not quite the same as the official Unicode property "XID_Start".
The difference is that this returns true only if the input character
also matches "isWORDCHAR". See the top of this section for an
explanation of the variants.
bool isIDFIRST (UV ch)
bool isIDFIRST_A (UV ch)
bool isIDFIRST_LC (UV ch)
bool isIDFIRST_LC_utf8_safe(U8 * s, U8 *end)
bool isIDFIRST_LC_uvchr (UV ch)
bool isIDFIRST_L1 (UV ch)
bool isIDFIRST_utf8 (U8 * s, U8 * end)
bool isIDFIRST_utf8_safe (U8 * s, U8 * end)
bool isIDFIRST_uvchr (UV ch)
"isLOWER"
"isLOWER_A"
"isLOWER_LC"
"isLOWER_LC_utf8_safe"
"isLOWER_LC_uvchr"
"isLOWER_L1"
"isLOWER_utf8"
"isLOWER_utf8_safe"
"isLOWER_uvchr"
Returns a boolean indicating whether the specified character is a
lowercase character, analogous to "m/[[:lower:]]/". See the top of
this section for an explanation of the variants
bool isLOWER (UV ch)
bool isLOWER_A (UV ch)
bool isLOWER_LC (UV ch)
bool isLOWER_LC_utf8_safe(U8 * s, U8 *end)
bool isLOWER_LC_uvchr (UV ch)
bool isLOWER_L1 (UV ch)
bool isLOWER_utf8 (U8 * s, U8 * end)
bool isLOWER_utf8_safe (U8 * s, U8 * end)
bool isLOWER_uvchr (UV ch)
"isOCTAL"
"isOCTAL_A"
"isOCTAL_L1"
Returns a boolean indicating whether the specified character is an
octal digit, [0-7]. The only two variants are "isOCTAL_A" and
"isOCTAL_L1"; each is identical to "isOCTAL".
bool isOCTAL(UV ch)
"isPRINT"
"isPRINT_A"
"isPRINT_LC"
"isPRINT_LC_utf8_safe"
"isPRINT_LC_uvchr"
"isPRINT_L1"
"isPRINT_utf8"
"isPRINT_utf8_safe"
"isPRINT_uvchr"
Returns a boolean indicating whether the specified character is a
printable character, analogous to "m/[[:print:]]/". See the top of
this section for an explanation of the variants.
bool isPRINT (UV ch)
bool isPRINT_A (UV ch)
bool isPRINT_LC (UV ch)
bool isPRINT_LC_utf8_safe(U8 * s, U8 *end)
bool isPRINT_LC_uvchr (UV ch)
bool isPRINT_L1 (UV ch)
bool isPRINT_utf8 (U8 * s, U8 * end)
bool isPRINT_utf8_safe (U8 * s, U8 * end)
bool isPRINT_uvchr (UV ch)
"isPSXSPC"
"isPSXSPC_A"
"isPSXSPC_LC"
"isPSXSPC_LC_utf8_safe"
"isPSXSPC_LC_uvchr"
"isPSXSPC_L1"
"isPSXSPC_utf8"
"isPSXSPC_utf8_safe"
"isPSXSPC_uvchr"
(short for Posix Space) Starting in 5.18, this is identical in all
its forms to the corresponding isSPACE() macros. The locale forms
of this macro are identical to their corresponding isSPACE() forms
in all Perl releases. In releases prior to 5.18, the non-locale
forms differ from their isSPACE() forms only in that the isSPACE()
forms don't match a Vertical Tab, and the isPSXSPC() forms do.
Otherwise they are identical. Thus this macro is analogous to what
"m/[[:space:]]/" matches in a regular expression. See the top of
this section for an explanation of the variants.
bool isPSXSPC (UV ch)
bool isPSXSPC_A (UV ch)
bool isPSXSPC_LC (UV ch)
bool isPSXSPC_LC_utf8_safe(U8 * s, U8 *end)
bool isPSXSPC_LC_uvchr (UV ch)
bool isPSXSPC_L1 (UV ch)
bool isPSXSPC_utf8 (U8 * s, U8 * end)
bool isPSXSPC_utf8_safe (U8 * s, U8 * end)
bool isPSXSPC_uvchr (UV ch)
"isPUNCT"
"isPUNCT_A"
"isPUNCT_LC"
"isPUNCT_LC_utf8_safe"
"isPUNCT_LC_uvchr"
"isPUNCT_L1"
"isPUNCT_utf8"
"isPUNCT_utf8_safe"
"isPUNCT_uvchr"
Returns a boolean indicating whether the specified character is a
punctuation character, analogous to "m/[[:punct:]]/". Note that the
definition of what is punctuation isn't as straightforward as one
might desire. See "POSIX Character Classes" in perlrecharclass for
details. See the top of this section for an explanation of the
variants.
bool isPUNCT (UV ch)
bool isPUNCT_A (UV ch)
bool isPUNCT_LC (UV ch)
bool isPUNCT_LC_utf8_safe(U8 * s, U8 *end)
bool isPUNCT_LC_uvchr (UV ch)
bool isPUNCT_L1 (UV ch)
bool isPUNCT_utf8 (U8 * s, U8 * end)
bool isPUNCT_utf8_safe (U8 * s, U8 * end)
bool isPUNCT_uvchr (UV ch)
"isSPACE"
"isSPACE_A"
"isSPACE_LC"
"isSPACE_LC_utf8_safe"
"isSPACE_LC_uvchr"
"isSPACE_L1"
"isSPACE_utf8"
"isSPACE_utf8_safe"
"isSPACE_uvchr"
Returns a boolean indicating whether the specified character is a
whitespace character. This is analogous to what "m/\s/" matches in
a regular expression. Starting in Perl 5.18 this also matches what
"m/[[:space:]]/" does. Prior to 5.18, only the locale forms of this
macro (the ones with "LC" in their names) matched precisely what
"m/[[:space:]]/" does. In those releases, the only difference, in
the non-locale variants, was that isSPACE() did not match a vertical
tab. (See "isPSXSPC" for a macro that matches a vertical tab in all
releases.) See the top of this section for an explanation of the
variants.
bool isSPACE (UV ch)
bool isSPACE_A (UV ch)
bool isSPACE_LC (UV ch)
bool isSPACE_LC_utf8_safe(U8 * s, U8 *end)
bool isSPACE_LC_uvchr (UV ch)
bool isSPACE_L1 (UV ch)
bool isSPACE_utf8 (U8 * s, U8 * end)
bool isSPACE_utf8_safe (U8 * s, U8 * end)
bool isSPACE_uvchr (UV ch)
"isUPPER"
"isUPPER_A"
"isUPPER_LC"
"isUPPER_LC_utf8_safe"
"isUPPER_LC_uvchr"
"isUPPER_L1"
"isUPPER_utf8"
"isUPPER_utf8_safe"
"isUPPER_uvchr"
Returns a boolean indicating whether the specified character is an
uppercase character, analogous to "m/[[:upper:]]/". See the top of
this section for an explanation of the variants.
bool isUPPER (UV ch)
bool isUPPER_A (UV ch)
bool isUPPER_LC (UV ch)
bool isUPPER_LC_utf8_safe(U8 * s, U8 *end)
bool isUPPER_LC_uvchr (UV ch)
bool isUPPER_L1 (UV ch)
bool isUPPER_utf8 (U8 * s, U8 * end)
bool isUPPER_utf8_safe (U8 * s, U8 * end)
bool isUPPER_uvchr (UV ch)
"isWORDCHAR"
"isWORDCHAR_A"
"isWORDCHAR_LC"
"isWORDCHAR_LC_utf8_safe"
"isWORDCHAR_LC_uvchr"
"isWORDCHAR_L1"
"isWORDCHAR_utf8"
"isWORDCHAR_utf8_safe"
"isWORDCHAR_uvchr"
Returns a boolean indicating whether the specified character is a
character that is a word character, analogous to what "m/\w/" and
"m/[[:word:]]/" match in a regular expression. A word character is
an alphabetic character, a decimal digit, a connecting punctuation
character (such as an underscore), or a "mark" character that
attaches to one of those (like some sort of accent).
See the top of this section for an explanation of the variants.
"isWORDCHAR_A", "isWORDCHAR_L1", "isWORDCHAR_uvchr",
"isWORDCHAR_LC", "isWORDCHAR_LC_uvchr", "isWORDCHAR_LC_utf8", and
"isWORDCHAR_LC_utf8_safe" are also as described there, but
additionally include the platform's native underscore.
bool isWORDCHAR (UV ch)
bool isWORDCHAR_A (UV ch)
bool isWORDCHAR_LC (UV ch)
bool isWORDCHAR_LC_utf8_safe(U8 * s, U8 *end)
bool isWORDCHAR_LC_uvchr (UV ch)
bool isWORDCHAR_L1 (UV ch)
bool isWORDCHAR_utf8 (U8 * s, U8 * end)
bool isWORDCHAR_utf8_safe (U8 * s, U8 * end)
bool isWORDCHAR_uvchr (UV ch)
"isXDIGIT"
"isXDIGIT_A"
"isXDIGIT_LC"
"isXDIGIT_LC_utf8_safe"
"isXDIGIT_LC_uvchr"
"isXDIGIT_L1"
"isXDIGIT_utf8"
"isXDIGIT_utf8_safe"
"isXDIGIT_uvchr"
Returns a boolean indicating whether the specified character is a
hexadecimal digit. In the ASCII range these are "[0-9A-Fa-f]".
Variants isXDIGIT_A() and isXDIGIT_L1() are identical to isXDIGIT().
See the top of this section for an explanation of the variants.
bool isXDIGIT (UV ch)
bool isXDIGIT_A (UV ch)
bool isXDIGIT_LC (UV ch)
bool isXDIGIT_LC_utf8_safe(U8 * s, U8 *end)
bool isXDIGIT_LC_uvchr (UV ch)
bool isXDIGIT_L1 (UV ch)
bool isXDIGIT_utf8 (U8 * s, U8 * end)
bool isXDIGIT_utf8_safe (U8 * s, U8 * end)
bool isXDIGIT_uvchr (UV ch)
Compiler and Preprocessor information
"CPPLAST"
This symbol is intended to be used along with "CPPRUN" in the same
manner symbol "CPPMINUS" is used with "CPPSTDIN". It contains either
"-" or "".
"CPPMINUS"
This symbol contains the second part of the string which will invoke
the C preprocessor on the standard input and produce to standard
output. This symbol will have the value "-" if "CPPSTDIN" needs a
minus to specify standard input, otherwise the value is "".
"CPPRUN"
This symbol contains the string which will invoke a C preprocessor
on the standard input and produce to standard output. It needs to
end with "CPPLAST", after all other preprocessor flags have been
specified. The main difference with "CPPSTDIN" is that this program
will never be a pointer to a shell wrapper, i.e. it will be empty if
no preprocessor is available directly to the user. Note that it may
well be different from the preprocessor used to compile the C
program.
"CPPSTDIN"
This symbol contains the first part of the string which will invoke
the C preprocessor on the standard input and produce to standard
output. Typical value of "cc -E" or "/lib/cpp", but it can also
call a wrapper. See "CPPRUN".
"HASATTRIBUTE_ALWAYS_INLINE"
Can we handle "GCC" attribute for functions that should always be
inlined.
"HASATTRIBUTE_DEPRECATED"
Can we handle "GCC" attribute for marking deprecated "APIs"
"HASATTRIBUTE_FORMAT"
Can we handle "GCC" attribute for checking printf-style formats
"HASATTRIBUTE_NONNULL"
Can we handle "GCC" attribute for nonnull function parms.
"HASATTRIBUTE_NORETURN"
Can we handle "GCC" attribute for functions that do not return
"HASATTRIBUTE_PURE"
Can we handle "GCC" attribute for pure functions
"HASATTRIBUTE_UNUSED"
Can we handle "GCC" attribute for unused variables and arguments
"HASATTRIBUTE_VISIBILITY"
Can we handle "GCC" attribute for functions that should have a
different visibility.
"HASATTRIBUTE_WARN_UNUSED_RESULT"
Can we handle "GCC" attribute for warning on unused results
"HAS_BUILTIN_ADD_OVERFLOW"
This symbol, if defined, indicates that the compiler supports
"__builtin_add_overflow" for adding integers with overflow checks.
"HAS_BUILTIN_CHOOSE_EXPR"
Can we handle "GCC" builtin for compile-time ternary-like
expressions
"HAS_BUILTIN_EXPECT"
Can we handle "GCC" builtin for telling that certain values are more
likely
"HAS_BUILTIN_MUL_OVERFLOW"
This symbol, if defined, indicates that the compiler supports
"__builtin_mul_overflow" for multiplying integers with overflow
checks.
"HAS_BUILTIN_SUB_OVERFLOW"
This symbol, if defined, indicates that the compiler supports
"__builtin_sub_overflow" for subtracting integers with overflow
checks.
"HAS_C99_VARIADIC_MACROS"
If defined, the compiler supports C99 variadic macros.
"HAS_STATIC_INLINE"
This symbol, if defined, indicates that the C compiler supports
C99-style static inline. That is, the function can't be called from
another translation unit.
"MEM_ALIGNBYTES"
This symbol contains the number of bytes required to align a double,
or a long double when applicable. Usual values are 2, 4 and 8. The
default is eight, for safety. For cross-compiling or multiarch
support, Configure will set a minimum of 8.
"PERL_STATIC_INLINE"
This symbol gives the best-guess incantation to use for static
inline functions. If "HAS_STATIC_INLINE" is defined, this will give
C99-style inline. If "HAS_STATIC_INLINE" is not defined, this will
give a plain 'static'. It will always be defined to something that
gives static linkage. Possibilities include
static inline (c99)
static __inline__ (gcc -ansi)
static __inline (MSVC)
static _inline (older MSVC)
static (c89 compilers)
"PERL_THREAD_LOCAL"
This symbol, if defined, gives a linkage specification for thread-
local storage. For example, for a C11 compiler this will be
"_Thread_local". Beware, some compilers are sensitive to the C
language standard they are told to parse. For example, suncc
defaults to C11, so our probe will report that "_Thread_local" can
be used. However, if the -std=c99 is later added to the compiler
flags, then "_Thread_local" will become a syntax error. Hence it is
important for these flags to be consistent between probing and use.
"U32_ALIGNMENT_REQUIRED"
This symbol, if defined, indicates that you must access character
data through U32-aligned pointers.
Compiler directives
"__ASSERT_"
This is a helper macro to avoid preprocessor issues, replaced by
nothing unless under DEBUGGING, where it expands to an assert of its
argument, followed by a comma (hence the comma operator). If we
just used a straight assert(), we would get a comma with nothing
before it when not DEBUGGING.
__ASSERT_(bool expr)
"ASSUME"
"ASSUME" is like assert(), but it has a benefit in a release build.
It is a hint to a compiler about a statement of fact in a function
call free expression, which allows the compiler to generate better
machine code. In a debug build, ASSUME(x) is a synonym for
assert(x). ASSUME(0) means the control path is unreachable. In a for
loop, "ASSUME" can be used to hint that a loop will run at least X
times. "ASSUME" is based off MSVC's "__assume" intrinsic function,
see its documents for more details.
ASSUME(bool expr)
"dNOOP"
Declare nothing; typically used as a placeholder to replace
something that used to declare something. Works on compilers that
require declarations before any code.
dNOOP;
"END_EXTERN_C"
When not compiling using C++, expands to nothing. Otherwise ends a
section of code already begun by a "START_EXTERN_C".
END_EXTERN_C
"EXTERN_C"
When not compiling using C++, expands to nothing. Otherwise is used
in a declaration of a function to indicate the function should have
external C linkage. This is required for things to work for just
about all functions with external linkage compiled into perl.
Often, you can use "START_EXTERN_C" ... "END_EXTERN_C" blocks
surrounding all your code that you need to have this linkage.
Example usage:
EXTERN_C int flock(int fd, int op);
"LIKELY"
Returns the input unchanged, but at the same time it gives a branch
prediction hint to the compiler that this condition is likely to be
true.
LIKELY(bool expr)
"NOOP"
Do nothing; typically used as a placeholder to replace something
that used to do something.
NOOP;
"PERL_UNUSED_ARG"
This is used to suppress compiler warnings that a parameter to a
function is not used. This situation can arise, for example, when a
parameter is needed under some configuration conditions, but not
others, so that C preprocessor conditional compilation causes it be
used just sometimes.
PERL_UNUSED_ARG(void x);
"PERL_UNUSED_CONTEXT"
This is used to suppress compiler warnings that the thread context
parameter to a function is not used. This situation can arise, for
example, when a C preprocessor conditional compilation causes it be
used just some times.
PERL_UNUSED_CONTEXT;
"PERL_UNUSED_DECL"
Tells the compiler that the parameter in the function prototype just
before it is not necessarily expected to be used in the function.
Not that many compilers understand this, so this should only be used
in cases where "PERL_UNUSED_ARG" can't conveniently be used.
Example usage:
Signal_t
Perl_perly_sighandler(int sig, Siginfo_t *sip PERL_UNUSED_DECL,
void *uap PERL_UNUSED_DECL, bool safe)
"PERL_UNUSED_RESULT"
This macro indicates to discard the return value of the function
call inside it, e.g.,
PERL_UNUSED_RESULT(foo(a, b))
The main reason for this is that the combination of "gcc
-Wunused-result" (part of "-Wall") and the
"__attribute__((warn_unused_result))" cannot be silenced with
casting to "void". This causes trouble when the system header files
use the attribute.
Use "PERL_UNUSED_RESULT" sparingly, though, since usually the
warning is there for a good reason: you might lose success/failure
information, or leak resources, or changes in resources.
But sometimes you just want to ignore the return value, e.g., on
codepaths soon ending up in abort, or in "best effort" attempts, or
in situations where there is no good way to handle failures.
Sometimes "PERL_UNUSED_RESULT" might not be the most natural way:
another possibility is that you can capture the return value and use
"PERL_UNUSED_VAR" on that.
PERL_UNUSED_RESULT(void x)
"PERL_UNUSED_VAR"
This is used to suppress compiler warnings that the variable x is
not used. This situation can arise, for example, when a C
preprocessor conditional compilation causes it be used just some
times.
PERL_UNUSED_VAR(void x);
"START_EXTERN_C"
When not compiling using C++, expands to nothing. Otherwise begins
a section of code in which every function will effectively have
"EXTERN_C" applied to it, that is to have external C linkage. The
section is ended by a "END_EXTERN_C".
START_EXTERN_C
"STATIC"
Described in perlguts.
"STMT_END"
"STMT_START"
These allow a series of statements in a macro to be used as a single
statement, as in
if (x) STMT_START { ... } STMT_END else ...
Note that you can't return a value out of this construct and cannot
use it as an operand to the comma operator. These limit its
utility.
But, a value could be returned by constructing the API so that a
pointer is passed and the macro dereferences this to set the return.
If the value can be any of various types, depending on context, you
can handle that situation in some situations by adding the type of
the return as an extra accompanying parameter:
#define foo(param, type) STMT_START {
type * param; *param = do_calc; ...
} STMT_END
This could be awkward, so consider instead using a C language
"static inline" function.
If you do use this construct, it is easy to forget that it is a
macro and not a function, and hence fall into traps that might not
show up until someone someday writes code which contains names that
clash with the ones you chose here, or calls it with a parameter
which is an expression with side effects, the consequences of which
you didn't think about. See "Writing safer macros" in perlhacktips
for how to avoid these.
"UNLIKELY"
Returns the input unchanged, but at the same time it gives a branch
prediction hint to the compiler that this condition is likely to be
false.
UNLIKELY(bool expr)
Compile-time scope hooks
"BhkDISABLE"
NOTE: "BhkDISABLE" is experimental and may change or be removed
without notice.
Temporarily disable an entry in this BHK structure, by clearing the
appropriate flag. "which" is a preprocessor token indicating which
entry to disable.
void BhkDISABLE(BHK *hk, token which)
"BhkENABLE"
NOTE: "BhkENABLE" is experimental and may change or be removed
without notice.
Re-enable an entry in this BHK structure, by setting the appropriate
flag. "which" is a preprocessor token indicating which entry to
enable. This will assert (under -DDEBUGGING) if the entry doesn't
contain a valid pointer.
void BhkENABLE(BHK *hk, token which)
"BhkENTRY_set"
NOTE: "BhkENTRY_set" is experimental and may change or be removed
without notice.
Set an entry in the BHK structure, and set the flags to indicate it
is valid. "which" is a preprocessing token indicating which entry
to set. The type of "ptr" depends on the entry.
void BhkENTRY_set(BHK *hk, token which, void *ptr)
"blockhook_register"
NOTE: "blockhook_register" is experimental and may change or be
removed without notice.
Register a set of hooks to be called when the Perl lexical scope
changes at compile time. See "Compile-time scope hooks" in
perlguts.
NOTE: "blockhook_register" must be explicitly called as
"Perl_blockhook_register" with an "aTHX_" parameter.
void Perl_blockhook_register(pTHX_ BHK *hk)
Concurrency
"aTHX"
Described in perlguts.
"aTHX_"
Described in perlguts.
"CPERLscope"
"DEPRECATED!" It is planned to remove "CPERLscope" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Now a no-op.
void CPERLscope(void x)
"dTHR"
Described in perlguts.
"dTHX"
Described in perlguts.
"dTHXa"
On threaded perls, set "pTHX" to "a"; on unthreaded perls, do
nothing
"dTHXoa"
Now a synonym for "dTHXa".
"dVAR"
This is now a synonym for dNOOP: declare nothing
"GETENV_PRESERVES_OTHER_THREAD"
This symbol, if defined, indicates that the getenv system call
doesn't zap the static buffer of getenv() in a different thread.
The typical getenv() implementation will return a pointer to the
proper position in **environ. But some may instead copy them to a
static buffer in getenv(). If there is a per-thread instance of
that buffer, or the return points to **environ, then a
many-reader/1-writer mutex will work; otherwise an exclusive locking
mutex is required to prevent races.
"HAS_PTHREAD_ATFORK"
This symbol, if defined, indicates that the "pthread_atfork" routine
is available to setup fork handlers.
"HAS_PTHREAD_ATTR_SETSCOPE"
This symbol, if defined, indicates that the "pthread_attr_setscope"
system call is available to set the contention scope attribute of a
thread attribute object.
"HAS_PTHREAD_YIELD"
This symbol, if defined, indicates that the "pthread_yield" routine
is available to yield the execution of the current thread.
"sched_yield" is preferable to "pthread_yield".
"HAS_SCHED_YIELD"
This symbol, if defined, indicates that the "sched_yield" routine is
available to yield the execution of the current thread.
"sched_yield" is preferable to "pthread_yield".
"I_MACH_CTHREADS"
This symbol, if defined, indicates to the C program that it should
include mach/cthreads.h.
#ifdef I_MACH_CTHREADS
#include <mach_cthreads.h>
#endif
"I_PTHREAD"
This symbol, if defined, indicates to the C program that it should
include pthread.h.
#ifdef I_PTHREAD
#include <pthread.h>
#endif
"MULTIPLICITY"
This symbol, if defined, indicates that Perl should be built to use
multiplicity.
"OLD_PTHREAD_CREATE_JOINABLE"
This symbol, if defined, indicates how to create pthread in joinable
(aka undetached) state. "NOTE": not defined if pthread.h already
has defined "PTHREAD_CREATE_JOINABLE" (the new version of the
constant). If defined, known values are "PTHREAD_CREATE_UNDETACHED"
and "__UNDETACHED".
"OLD_PTHREADS_API"
This symbol, if defined, indicates that Perl should be built to use
the old draft "POSIX" threads "API".
"PERL_IMPLICIT_CONTEXT"
Described in perlguts.
"PERL_NO_GET_CONTEXT"
Described in perlguts.
"pTHX"
Described in perlguts.
"pTHX_"
Described in perlguts.
"SCHED_YIELD"
This symbol defines the way to yield the execution of the current
thread. Known ways are "sched_yield", "pthread_yield", and
"pthread_yield" with "NULL".
COPs and Hint Hashes
"cop_fetch_label"
NOTE: "cop_fetch_label" is experimental and may change or be removed
without notice.
Returns the label attached to a cop, and stores its length in bytes
into *len. Upon return, *flags will be set to either "SVf_UTF8" or
0.
Alternatively, use the macro "CopLABEL_len_flags"; or if you don't
need to know if the label is UTF-8 or not, the macro "CopLABEL_len";
or if you additionally don't need to know the length, "CopLABEL".
const char * cop_fetch_label(COP * const cop, STRLEN *len,
U32 *flags)
"CopFILE"
Returns the name of the file associated with the "COP" "c"
const char * CopFILE(const COP * c)
"CopFILEAV"
Returns the AV associated with the "COP" "c", creating it if
necessary.
AV * CopFILEAV(const COP * c)
"CopFILEAVn"
Returns the AV associated with the "COP" "c", returning NULL if it
doesn't already exist.
AV * CopFILEAVn(const COP * c)
"CopFILE_copy"
Efficiently copies the cop file name from one COP to another. Wraps
the required logic to do a refcounted copy under threads or not.
void CopFILE_copy(COP * dst, COP * src)
"CopFILE_free"
Frees the file data in a cop. Under the hood this is a refcounting
operation.
void CopFILE_free(COP * c)
"CopFILEGV"
Returns the GV associated with the "COP" "c"
GV * CopFILEGV(const COP * c)
"CopFILEGV_set"
Available only on unthreaded perls. Makes "pv" the name of the file
associated with the "COP" "c"
void CopFILEGV_set(COP *c, GV *gv)
"CopFILE_LEN"
Returns the length of the file associated with the "COP" "c"
const char * CopFILE_LEN(const COP * c)
"CopFILE_set"
Makes "pv" the name of the file associated with the "COP" "c"
void CopFILE_set(COP * c, const char * pv)
"CopFILE_setn"
Makes "pv" the name of the file associated with the "COP" "c"
void CopFILE_setn(COP * c, const char * pv, STRLEN len)
"CopFILESV"
Returns the SV associated with the "COP" "c"
SV * CopFILESV(const COP * c)
"cophh_copy"
NOTE: "cophh_copy" is experimental and may change or be removed
without notice.
Make and return a complete copy of the cop hints hash "cophh".
COPHH * cophh_copy(COPHH *cophh)
"cophh_delete_pv"
"cophh_delete_pvn"
"cophh_delete_pvs"
"cophh_delete_sv"
NOTE: all these forms are experimental and may change or be removed
without notice.
These delete a key and its associated value from the cop hints hash
"cophh", and return the modified hash. The returned hash pointer is
in general not the same as the hash pointer that was passed in. The
input hash is consumed by the function, and the pointer to it must
not be subsequently used. Use "cophh_copy" if you need both hashes.
The forms differ in how the key is specified. In all forms, the key
is pointed to by "key". In the plain "pv" form, the key is a C
language NUL-terminated string. In the "pvs" form, the key is a C
language string literal. In the "pvn" form, an additional
parameter, "keylen", specifies the length of the string, which
hence, may contain embedded-NUL characters. In the "sv" form, *key
is an SV, and the key is the PV extracted from that. using
"SvPV_const".
"hash" is a precomputed hash of the key string, or zero if it has
not been precomputed. This parameter is omitted from the "pvs"
form, as it is computed automatically at compile time.
The only flag currently used from the "flags" parameter is
"COPHH_KEY_UTF8". It is illegal to set this in the "sv" form. In
the "pv*" forms, it specifies whether the key octets are interpreted
as UTF-8 (if set) or as Latin-1 (if cleared). The "sv" form uses
the underlying SV to determine the UTF-8ness of the octets.
COPHH * cophh_delete_pv (COPHH *cophh, const char *key, U32 hash,
U32 flags)
COPHH * cophh_delete_pvn(COPHH *cophh, const char *key,
STRLEN keylen, U32 hash, U32 flags)
COPHH * cophh_delete_pvs(COPHH *cophh, "key", U32 flags)
COPHH * cophh_delete_sv (COPHH *cophh, SV *key, U32 hash,
U32 flags)
"cophh_exists_pvn"
NOTE: "cophh_exists_pvn" is experimental and may change or be
removed without notice.
These look up the hint entry in the cop "cop" with the key specified
by "key" (and "keylen" in the "pvn" form), returning true if a value
exists, and false otherwise.
The forms differ in how the key is specified. In the plain "pv"
form, the key is a C language NUL-terminated string. In the "pvs"
form, the key is a C language string literal. In the "pvn" form, an
additional parameter, "keylen", specifies the length of the string,
which hence, may contain embedded-NUL characters. In the "sv" form,
*key is an SV, and the key is the PV extracted from that. using
"SvPV_const".
"hash" is a precomputed hash of the key string, or zero if it has
not been precomputed. This parameter is omitted from the "pvs"
form, as it is computed automatically at compile time.
The only flag currently used from the "flags" parameter is
"COPHH_KEY_UTF8". It is illegal to set this in the "sv" form. In
the "pv*" forms, it specifies whether the key octets are interpreted
as UTF-8 (if set) or as Latin-1 (if cleared). The "sv" form uses
the underlying SV to determine the UTF-8ness of the octets.
bool cophh_exists_pvn(const COPHH *cophh, const char *key,
STRLEN keylen, U32 hash, U32 flags)
"cophh_fetch_pv"
"cophh_fetch_pvn"
"cophh_fetch_pvs"
"cophh_fetch_sv"
NOTE: all these forms are experimental and may change or be removed
without notice.
These look up the entry in the cop hints hash "cophh" with the key
specified by "key" (and "keylen" in the "pvn" form), returning that
value as a mortal scalar copy, or &PL_sv_placeholder if there is no
value associated with the key.
The forms differ in how the key is specified. In the plain "pv"
form, the key is a C language NUL-terminated string. In the "pvs"
form, the key is a C language string literal. In the "pvn" form, an
additional parameter, "keylen", specifies the length of the string,
which hence, may contain embedded-NUL characters. In the "sv" form,
*key is an SV, and the key is the PV extracted from that. using
"SvPV_const".
"hash" is a precomputed hash of the key string, or zero if it has
not been precomputed. This parameter is omitted from the "pvs"
form, as it is computed automatically at compile time.
The only flag currently used from the "flags" parameter is
"COPHH_KEY_UTF8". It is illegal to set this in the "sv" form. In
the "pv*" forms, it specifies whether the key octets are interpreted
as UTF-8 (if set) or as Latin-1 (if cleared). The "sv" form uses
the underlying SV to determine the UTF-8ness of the octets.
SV * cophh_fetch_pv (const COPHH *cophh, const char *key,
U32 hash, U32 flags)
SV * cophh_fetch_pvn(const COPHH *cophh, const char *key,
STRLEN keylen, U32 hash, U32 flags)
SV * cophh_fetch_pvs(const COPHH *cophh, "key", U32 flags)
SV * cophh_fetch_sv (const COPHH *cophh, SV *key, U32 hash,
U32 flags)
"cophh_free"
NOTE: "cophh_free" is experimental and may change or be removed
without notice.
Discard the cop hints hash "cophh", freeing all resources associated
with it.
void cophh_free(COPHH *cophh)
"cophh_2hv"
NOTE: "cophh_2hv" is experimental and may change or be removed
without notice.
Generates and returns a standard Perl hash representing the full set
of key/value pairs in the cop hints hash "cophh". "flags" is
currently unused and must be zero.
HV * cophh_2hv(const COPHH *cophh, U32 flags)
"cophh_new_empty"
NOTE: "cophh_new_empty" is experimental and may change or be removed
without notice.
Generate and return a fresh cop hints hash containing no entries.
COPHH * cophh_new_empty()
"cophh_store_pv"
"cophh_store_pvn"
"cophh_store_pvs"
"cophh_store_sv"
NOTE: all these forms are experimental and may change or be removed
without notice.
These store a value, associated with a key, in the cop hints hash
"cophh", and return the modified hash. The returned hash pointer is
in general not the same as the hash pointer that was passed in. The
input hash is consumed by the function, and the pointer to it must
not be subsequently used. Use "cophh_copy" if you need both hashes.
"value" is the scalar value to store for this key. "value" is
copied by these functions, which thus do not take ownership of any
reference to it, and hence later changes to the scalar will not be
reflected in the value visible in the cop hints hash. Complex types
of scalar will not be stored with referential integrity, but will be
coerced to strings.
The forms differ in how the key is specified. In all forms, the key
is pointed to by "key". In the plain "pv" form, the key is a C
language NUL-terminated string. In the "pvs" form, the key is a C
language string literal. In the "pvn" form, an additional
parameter, "keylen", specifies the length of the string, which
hence, may contain embedded-NUL characters. In the "sv" form, *key
is an SV, and the key is the PV extracted from that. using
"SvPV_const".
"hash" is a precomputed hash of the key string, or zero if it has
not been precomputed. This parameter is omitted from the "pvs"
form, as it is computed automatically at compile time.
The only flag currently used from the "flags" parameter is
"COPHH_KEY_UTF8". It is illegal to set this in the "sv" form. In
the "pv*" forms, it specifies whether the key octets are interpreted
as UTF-8 (if set) or as Latin-1 (if cleared). The "sv" form uses
the underlying SV to determine the UTF-8ness of the octets.
COPHH * cophh_store_pv (COPHH *cophh, const char *key, U32 hash,
SV *value, U32 flags)
COPHH * cophh_store_pvn(COPHH *cophh, const char *key,
STRLEN keylen, U32 hash, SV *value,
U32 flags)
COPHH * cophh_store_pvs(COPHH *cophh, "key", SV *value,
U32 flags)
COPHH * cophh_store_sv (COPHH *cophh, SV *key, U32 hash,
SV *value, U32 flags)
"cop_hints_exists_pv"
"cop_hints_exists_pvn"
"cop_hints_exists_pvs"
"cop_hints_exists_sv"
These look up the hint entry in the cop "cop" with the key specified
by "key" (and "keylen" in the "pvn" form), returning true if a value
exists, and false otherwise.
The forms differ in how the key is specified. In all forms, the key
is pointed to by "key". In the plain "pv" form, the key is a C
language NUL-terminated string. In the "pvs" form, the key is a C
language string literal. In the "pvn" form, an additional
parameter, "keylen", specifies the length of the string, which
hence, may contain embedded-NUL characters. In the "sv" form, *key
is an SV, and the key is the PV extracted from that. using
"SvPV_const".
"hash" is a precomputed hash of the key string, or zero if it has
not been precomputed. This parameter is omitted from the "pvs"
form, as it is computed automatically at compile time.
The only flag currently used from the "flags" parameter is
"COPHH_KEY_UTF8". It is illegal to set this in the "sv" form. In
the "pv*" forms, it specifies whether the key octets are interpreted
as UTF-8 (if set) or as Latin-1 (if cleared). The "sv" form uses
the underlying SV to determine the UTF-8ness of the octets.
bool cop_hints_exists_pv (const COP *cop, const char *key,
U32 hash, U32 flags)
bool cop_hints_exists_pvn(const COP *cop, const char *key,
STRLEN keylen, U32 hash, U32 flags)
bool cop_hints_exists_pvs(const COP *cop, "key", U32 flags)
bool cop_hints_exists_sv (const COP *cop, SV *key, U32 hash,
U32 flags)
"cop_hints_fetch_pv"
"cop_hints_fetch_pvn"
"cop_hints_fetch_pvs"
"cop_hints_fetch_sv"
These look up the hint entry in the cop "cop" with the key specified
by "key" (and "keylen" in the "pvn" form), returning that value as a
mortal scalar copy, or &PL_sv_placeholder if there is no value
associated with the key.
The forms differ in how the key is specified. In the plain "pv"
form, the key is a C language NUL-terminated string. In the "pvs"
form, the key is a C language string literal. In the "pvn" form, an
additional parameter, "keylen", specifies the length of the string,
which hence, may contain embedded-NUL characters. In the "sv" form,
*key is an SV, and the key is the PV extracted from that. using
"SvPV_const".
"hash" is a precomputed hash of the key string, or zero if it has
not been precomputed. This parameter is omitted from the "pvs"
form, as it is computed automatically at compile time.
The only flag currently used from the "flags" parameter is
"COPHH_KEY_UTF8". It is illegal to set this in the "sv" form. In
the "pv*" forms, it specifies whether the key octets are interpreted
as UTF-8 (if set) or as Latin-1 (if cleared). The "sv" form uses
the underlying SV to determine the UTF-8ness of the octets.
SV * cop_hints_fetch_pv (const COP *cop, const char *key,
U32 hash, U32 flags)
SV * cop_hints_fetch_pvn(const COP *cop, const char *key,
STRLEN keylen, U32 hash, U32 flags)
SV * cop_hints_fetch_pvs(const COP *cop, "key", U32 flags)
SV * cop_hints_fetch_sv (const COP *cop, SV *key, U32 hash,
U32 flags)
"cop_hints_2hv"
Generates and returns a standard Perl hash representing the full set
of hint entries in the cop "cop". "flags" is currently unused and
must be zero.
HV * cop_hints_2hv(const COP *cop, U32 flags)
"CopLABEL"
"CopLABEL_len"
"CopLABEL_len_flags"
These return the label attached to a cop.
"CopLABEL_len" and "CopLABEL_len_flags" additionally store the
number of bytes comprising the returned label into *len.
"CopLABEL_len_flags" additionally returns the UTF-8ness of the
returned label, by setting *flags to 0 or "SVf_UTF8".
const char * CopLABEL (COP *const cop)
const char * CopLABEL_len (COP *const cop, STRLEN *len)
const char * CopLABEL_len_flags(COP *const cop, STRLEN *len,
U32 *flags)
"CopLINE"
Returns the line number in the source code associated with the "COP"
"c"
line_t CopLINE(const COP * c)
"CopSTASH"
Returns the stash associated with "c".
HV * CopSTASH(const COP * c)
"CopSTASH_eq"
Returns a boolean as to whether or not "hv" is the stash associated
with "c".
bool CopSTASH_eq(const COP * c, const HV * hv)
"CopSTASHPV"
Returns the package name of the stash associated with "c", or "NULL"
if no associated stash
char * CopSTASHPV(const COP * c)
"CopSTASHPV_set"
Set the package name of the stash associated with "c", to the NUL-
terminated C string "p", creating the package if necessary.
void CopSTASHPV_set(COP * c, const char * pv)
"CopSTASH_set"
Set the stash associated with "c" to "hv".
bool CopSTASH_set(COP * c, HV * hv)
"cop_store_label"
NOTE: "cop_store_label" is experimental and may change or be removed
without notice.
Save a label into a "cop_hints_hash". You need to set flags to
"SVf_UTF8" for a UTF-8 label. Any other flag is ignored.
void cop_store_label(COP * const cop, const char *label,
STRLEN len, U32 flags)
"PERL_SI"
Use this typedef to declare variables that are to hold "struct
stackinfo".
"PL_curcop"
The currently active COP (control op) roughly representing the
current statement in the source.
On threaded perls, each thread has an independent copy of this
variable; each initialized at creation time with the current value
of the creating thread's copy.
COP* PL_curcop
"RCPV_LEN"
Returns the length of a pv created with rcpv_new(). Note that this
reflects the length of the string from the callers point of view, it
does not include the mandatory null which is always injected at the
end of the string by rcpv_new(). No checks are performed to ensure
that "pv" was actually allocated with rcpv_new(), it is the callers
responsibility to ensure that this is the case.
RCPV * RCPV_LEN(char *pv)
"RCPV_REFCNT_dec"
Decrements the refcount for a "char *" pointer which was created
with a call to rcpv_new(). Same as calling rcpv_free(). No checks
are performed to ensure that "pv" was actually allocated with
rcpv_new(), it is the callers responsibility to ensure that this is
the case.
RCPV * RCPV_REFCNT_dec(char *pv)
"RCPV_REFCNT_inc"
Increments the refcount for a "char *" pointer which was created
with a call to rcpv_new(). Same as calling rcpv_copy(). No checks
are performed to ensure that "pv" was actually allocated with
rcpv_new(), it is the callers responsibility to ensure that this is
the case.
RCPV * RCPV_REFCNT_inc(char *pv)
"RCPV_REFCOUNT"
Returns the refcount for a pv created with rcpv_new(). No checks
are performed to ensure that "pv" was actually allocated with
rcpv_new(), it is the callers responsibility to ensure that this is
the case.
RCPV * RCPV_REFCOUNT(char *pv)
"RCPVx"
Returns the RCPV structure (struct rcpv) for a refcounted string pv
created with rcpv_new(). No checks are performed to ensure that
"pv" was actually allocated with rcpv_new(), it is the callers
responsibility to ensure that this is the case.
RCPV * RCPVx(char *pv)
Custom Operators
"custom_op_register"
Register a custom op. See "Custom Operators" in perlguts.
NOTE: "custom_op_register" must be explicitly called as
"Perl_custom_op_register" with an "aTHX_" parameter.
void Perl_custom_op_register(pTHX_ Perl_ppaddr_t ppaddr,
const XOP *xop)
"Perl_custom_op_xop"
Return the XOP structure for a given custom op. This macro should
be considered internal to "OP_NAME" and the other access macros: use
them instead. This macro does call a function. Prior to 5.19.6,
this was implemented as a function.
const XOP * Perl_custom_op_xop(pTHX_ const OP *o)
"XopDISABLE"
Temporarily disable a member of the XOP, by clearing the appropriate
flag.
void XopDISABLE(XOP *xop, token which)
"XopENABLE"
Reenable a member of the XOP which has been disabled.
void XopENABLE(XOP *xop, token which)
"XopENTRY"
Return a member of the XOP structure. "which" is a cpp token
indicating which entry to return. If the member is not set this
will return a default value. The return type depends on "which".
This macro evaluates its arguments more than once. If you are using
"Perl_custom_op_xop" to retrieve a "XOP *" from a "OP *", use the
more efficient "XopENTRYCUSTOM" instead.
XopENTRY(XOP *xop, token which)
"XopENTRYCUSTOM"
Exactly like "XopENTRY(XopENTRY(Perl_custom_op_xop(aTHX_ o), which)"
but more efficient. The "which" parameter is identical to
"XopENTRY".
XopENTRYCUSTOM(const OP *o, token which)
"XopENTRY_set"
Set a member of the XOP structure. "which" is a cpp token
indicating which entry to set. See "Custom Operators" in perlguts
for details about the available members and how they are used. This
macro evaluates its argument more than once.
void XopENTRY_set(XOP *xop, token which, value)
"XopFLAGS"
Return the XOP's flags.
U32 XopFLAGS(XOP *xop)
CV Handling
This section documents functions to manipulate CVs which are code-
values, meaning subroutines. For more information, see perlguts.
"caller_cx"
The XSUB-writer's equivalent of caller(). The returned
"PERL_CONTEXT" structure can be interrogated to find all the
information returned to Perl by "caller". Note that XSUBs don't get
a stack frame, so "caller_cx(0, NULL)" will return information for
the immediately-surrounding Perl code.
This function skips over the automatic calls to &DB::sub made on the
behalf of the debugger. If the stack frame requested was a sub
called by "DB::sub", the return value will be the frame for the call
to "DB::sub", since that has the correct line number/etc. for the
call site. If dbcxp is non-"NULL", it will be set to a pointer to
the frame for the sub call itself.
const PERL_CONTEXT * caller_cx(I32 level,
const PERL_CONTEXT **dbcxp)
"CvDEPTH"
Returns the recursion level of the CV "sv". Hence >= 2 indicates we
are in a recursive call.
I32 * CvDEPTH(const CV * const sv)
"CvGV"
Returns the GV associated with the CV "sv", reifying it if
necessary.
GV * CvGV(CV *sv)
"CvSTASH"
Returns the stash of the CV. A stash is the symbol table hash,
containing the package-scoped variables in the package where the
subroutine was defined. For more information, see perlguts.
This also has a special use with XS AUTOLOAD subs. See "Autoloading
with XSUBs" in perlguts.
HV* CvSTASH(CV* cv)
"find_runcv"
Locate the CV corresponding to the currently executing sub or eval.
If "db_seqp" is non_null, skip CVs that are in the DB package and
populate *db_seqp with the cop sequence number at the point that the
DB:: code was entered. (This allows debuggers to eval in the scope
of the breakpoint rather than in the scope of the debugger itself.)
CV * find_runcv(U32 *db_seqp)
"get_cv"
"get_cvn_flags"
"get_cvs"
These return the CV of the specified Perl subroutine. "flags" are
passed to "gv_fetchpvn_flags". If "GV_ADD" is set and the Perl
subroutine does not exist then it will be declared (which has the
same effect as saying "sub name;"). If "GV_ADD" is not set and the
subroutine does not exist, then NULL is returned.
The forms differ only in how the subroutine is specified.. With
"get_cvs", the name is a literal C string, enclosed in double
quotes. With "get_cv", the name is given by the "name" parameter,
which must be a NUL-terminated C string. With "get_cvn_flags", the
name is also given by the "name" parameter, but it is a Perl string
(possibly containing embedded NUL bytes), and its length in bytes is
contained in the "len" parameter.
NOTE: the perl_get_cv() form is deprecated.
NOTE: the perl_get_cvn_flags() form is deprecated.
NOTE: the perl_get_cvs() form is deprecated.
CV * get_cv (const char *name, I32 flags)
CV * get_cvn_flags(const char *name, STRLEN len, I32 flags)
CV * get_cvs ("string", I32 flags)
"Nullcv"
"DEPRECATED!" It is planned to remove "Nullcv" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Null CV pointer.
(deprecated - use "(CV *)NULL" instead)
Debugging
"av_dump"
Dumps the contents of an AV to the "STDERR" filehandle, Similar to
using Devel::Peek on an arrayref but does not expect an RV wrapper.
Dumps contents to a depth of 3 levels deep.
void av_dump(AV *av)
"deb"
"deb_nocontext"
When perl is compiled with "-DDEBUGGING", this prints to STDERR the
information given by the arguments, prefaced by the name of the file
containing the script causing the call, and the line number within
that file.
If the "v" (verbose) debugging option is in effect, the process id
is also printed.
The two forms differ only in that "deb_nocontext" does not take a
thread context ("aTHX") parameter, so is used in situations where
the caller doesn't already have the thread context.
NOTE: "deb" must be explicitly called as "Perl_deb" with an "aTHX_"
parameter.
void Perl_deb (pTHX_ const char *pat, ...)
void deb_nocontext(const char *pat, ...)
"debstack"
Dump the current stack
I32 debstack()
"dump_all"
Dumps the entire optree of the current program starting at
"PL_main_root" to "STDERR". Also dumps the optrees for all visible
subroutines in "PL_defstash".
void dump_all()
"dump_c_backtrace"
Dumps the C backtrace to the given "fp".
Returns true if a backtrace could be retrieved, false if not.
bool dump_c_backtrace(PerlIO *fp, int max_depth, int skip)
"dump_eval"
Described in perlguts.
void dump_eval()
"dump_form"
Dumps the contents of the format contained in the GV "gv" to
"STDERR", or a message that one doesn't exist.
void dump_form(const GV *gv)
"dump_packsubs"
Dumps the optrees for all visible subroutines in "stash".
void dump_packsubs(const HV *stash)
"dump_sub"
Described in perlguts.
void dump_sub(const GV *gv)
"get_c_backtrace_dump"
Returns a SV containing a dump of "depth" frames of the call stack,
skipping the "skip" innermost ones. "depth" of 20 is usually
enough.
The appended output looks like:
...
1 10e004812:0082 Perl_croak util.c:1716 /usr/bin/perl
2 10df8d6d2:1d72 perl_parse perl.c:3975 /usr/bin/perl
...
The fields are tab-separated. The first column is the depth (zero
being the innermost non-skipped frame). In the hex:offset, the hex
is where the program counter was in "S_parse_body", and the :offset
(might be missing) tells how much inside the "S_parse_body" the
program counter was.
The "util.c:1716" is the source code file and line number.
The /usr/bin/perl is obvious (hopefully).
Unknowns are "-". Unknowns can happen unfortunately quite easily:
if the platform doesn't support retrieving the information; if the
binary is missing the debug information; if the optimizer has
transformed the code by for example inlining.
SV * get_c_backtrace_dump(int max_depth, int skip)
"gv_dump"
Dump the name and, if they differ, the effective name of the GV "gv"
to "STDERR".
void gv_dump(GV *gv)
"HAS_BACKTRACE"
This symbol, if defined, indicates that the backtrace() routine is
available to get a stack trace. The execinfo.h header must be
included to use this routine.
"hv_dump"
Dumps the contents of an HV to the "STDERR" filehandle. Similar to
using Devel::Peek on an hashref but does not expect an RV wrapper.
Dumps contents to a depth of 3 levels deep.
void hv_dump(HV *hv)
"magic_dump"
Dumps the contents of the MAGIC "mg" to "STDERR".
void magic_dump(const MAGIC *mg)
"op_class"
Given an op, determine what type of struct it has been allocated as.
Returns one of the OPclass enums, such as OPclass_LISTOP.
OPclass op_class(const OP *o)
"op_dump"
Dumps the optree starting at OP "o" to "STDERR".
void op_dump(const OP *o)
"PL_op"
Described in perlhacktips.
"PL_runops"
Described in perlguts.
"PL_sv_serial"
Described in perlhacktips.
"pmop_dump"
Dump an OP that is related to Pattern Matching, such as
"s/foo/bar/"; these require special handling.
void pmop_dump(PMOP *pm)
"sv_dump"
Dumps the contents of an SV to the "STDERR" filehandle.
For an example of its output, see Devel::Peek. If the item is an
SvROK it will dump items to a depth of 4, otherwise it will dump
only the top level item, which means that it will not dump the
contents of an AV * or HV *. For that use av_dump() or hv_dump().
void sv_dump(SV *sv)
"sv_dump_depth"
Dumps the contents of an SV to the "STDERR" filehandle to the depth
requested. This function can be used on any SV derived type (GV, HV,
AV) with an appropriate cast. This is a more flexible variant of
sv_dump(). For example
HV *hv = ...;
sv_dump_depth((SV*)hv, 2);
would dump the hv, its keys and values, but would not recurse into
any RV values.
void sv_dump_depth(SV *sv, I32 depth)
"vdeb"
This is like "deb", but "args" are an encapsulated argument list.
void vdeb(const char *pat, va_list *args)
Display functions
"form"
"form_nocontext"
These take a sprintf-style format pattern and conventional (non-SV)
arguments and return the formatted string.
(char *) Perl_form(aTHX_ const char* pat, ...)
They can be used any place a string (char *) is required:
char * s = form_nocontext("%d.%d", major, minor);
They each return a temporary that will be freed "soon",
automatically by the system, at the same time that SVs operated on
by "sv_2mortal" are freed.
Use the result immediately, or copy to a stable place for longer
retention. This is contrary to the incorrect previous documentation
of these that claimed that the return was a single per-thread
buffer. That was (and is) actually true only when these are called
during global destruction.
The two forms differ only in that "form_nocontext" does not take a
thread context ("aTHX") parameter, so is used in situations where
the caller doesn't already have the thread context.
"vform" is the same except the arguments are an encapsulated
argument list.
NOTE: "form" must be explicitly called as "Perl_form" with an
"aTHX_" parameter.
char * Perl_form (pTHX_ const char *pat, ...)
char * form_nocontext(const char *pat, ...)
"mess"
"mess_nocontext"
These take a sprintf-style format pattern and argument list, which
are used to generate a string message. If the message does not end
with a newline, then it will be extended with some indication of the
current location in the code, as described for "mess_sv".
Normally, the resulting message is returned in a new mortal SV. But
during global destruction a single SV may be shared between uses of
this function.
The two forms differ only in that "mess_nocontext" does not take a
thread context ("aTHX") parameter, so is used in situations where
the caller doesn't already have the thread context.
NOTE: "mess" must be explicitly called as "Perl_mess" with an
"aTHX_" parameter.
SV * Perl_mess (pTHX_ const char *pat, ...)
SV * mess_nocontext(const char *pat, ...)
"mess_sv"
Expands a message, intended for the user, to include an indication
of the current location in the code, if the message does not already
appear to be complete.
"basemsg" is the initial message or object. If it is a reference,
it will be used as-is and will be the result of this function.
Otherwise it is used as a string, and if it already ends with a
newline, it is taken to be complete, and the result of this function
will be the same string. If the message does not end with a
newline, then a segment such as "at foo.pl line 37" will be
appended, and possibly other clauses indicating the current state of
execution. The resulting message will end with a dot and a newline.
Normally, the resulting message is returned in a new mortal SV.
During global destruction a single SV may be shared between uses of
this function. If "consume" is true, then the function is permitted
(but not required) to modify and return "basemsg" instead of
allocating a new SV.
SV * mess_sv(SV *basemsg, bool consume)
"pv_display"
Similar to
pv_escape(dsv,pv,cur,pvlim,PERL_PV_ESCAPE_QUOTE);
except that an additional "\0" will be appended to the string when
len > cur and pv[cur] is "\0".
Note that the final string may be up to 7 chars longer than pvlim.
char * pv_display(SV *dsv, const char *pv, STRLEN cur,
STRLEN len, STRLEN pvlim)
"pv_escape"
Escapes at most the first "count" chars of "pv" and puts the results
into "dsv" such that the size of the escaped string will not exceed
"max" chars and will not contain any incomplete escape sequences.
The number of bytes escaped will be returned in the "STRLEN
*escaped" parameter if it is not null. When the "dsv" parameter is
null no escaping actually occurs, but the number of bytes that would
be escaped were it not null will be calculated.
If flags contains "PERL_PV_ESCAPE_QUOTE" then any double quotes in
the string will also be escaped.
Normally the SV will be cleared before the escaped string is
prepared, but when "PERL_PV_ESCAPE_NOCLEAR" is set this will not
occur.
If "PERL_PV_ESCAPE_UNI" is set then the input string is treated as
UTF-8. If "PERL_PV_ESCAPE_UNI_DETECT" is set then the input string
is scanned using is_utf8_string() to determine if it is UTF-8.
If "PERL_PV_ESCAPE_ALL" is set then all input chars will be output
using "\x01F1" style escapes, otherwise if "PERL_PV_ESCAPE_NONASCII"
is set, only non-ASCII chars will be escaped using this style;
otherwise, only chars above 255 will be so escaped; other non
printable chars will use octal or common escaped patterns like "\n".
Otherwise, if "PERL_PV_ESCAPE_NOBACKSLASH" then all chars below 255
will be treated as printable and will be output as literals. The
"PERL_PV_ESCAPE_NON_WC" modifies the previous rules to cause word
chars, unicode or otherwise, to be output as literals, note this
uses the *unicode* rules for deciding on word characters.
If "PERL_PV_ESCAPE_FIRSTCHAR" is set then only the first char of the
string will be escaped, regardless of max. If the output is to be in
hex, then it will be returned as a plain hex sequence. Thus the
output will either be a single char, an octal escape sequence, a
special escape like "\n" or a hex value.
If "PERL_PV_ESCAPE_RE" is set then the escape char used will be a
"%" and not a "\\". This is because regexes very often contain
backslashed sequences, whereas "%" is not a particularly common
character in patterns.
Returns a pointer to the escaped text as held by "dsv".
char * pv_escape(SV *dsv, char const * const str,
const STRLEN count, STRLEN max,
STRLEN * const escaped, U32 flags)
"pv_pretty"
Converts a string into something presentable, handling escaping via
pv_escape() and supporting quoting and ellipses.
If the "PERL_PV_PRETTY_QUOTE" flag is set then the result will be
double quoted with any double quotes in the string escaped.
Otherwise if the "PERL_PV_PRETTY_LTGT" flag is set then the result
be wrapped in angle brackets.
If the "PERL_PV_PRETTY_ELLIPSES" flag is set and not all characters
in string were output then an ellipsis "..." will be appended to the
string. Note that this happens AFTER it has been quoted.
If "start_color" is non-null then it will be inserted after the
opening quote (if there is one) but before the escaped text. If
"end_color" is non-null then it will be inserted after the escaped
text but before any quotes or ellipses.
Returns a pointer to the prettified text as held by "dsv".
char * pv_pretty(SV *dsv, char const * const str,
const STRLEN count, const STRLEN max,
char const * const start_color,
char const * const end_color, const U32 flags)
"vform"
Like "form" except the arguments are an encapsulated argument list.
char * vform(const char *pat, va_list *args)
"vmess"
"pat" and "args" are a sprintf-style format pattern and encapsulated
argument list, respectively. These are used to generate a string
message. If the message does not end with a newline, then it will
be extended with some indication of the current location in the
code, as described for "mess_sv".
Normally, the resulting message is returned in a new mortal SV.
During global destruction a single SV may be shared between uses of
this function.
SV * vmess(const char *pat, va_list *args)
Embedding, Threads, and Interpreter Cloning
"call_atexit"
Add a function "fn" to the list of functions to be called at global
destruction. "ptr" will be passed as an argument to "fn"; it can
point to a "struct" so that you can pass anything you want.
Note that under threads, "fn" may run multiple times. This is
because the list is executed each time the current or any descendent
thread terminates.
void call_atexit(ATEXIT_t fn, void *ptr)
"cv_clone"
Clone a CV, making a lexical closure. "proto" supplies the
prototype of the function: its code, pad structure, and other
attributes. The prototype is combined with a capture of outer
lexicals to which the code refers, which are taken from the
currently-executing instance of the immediately surrounding code.
CV * cv_clone(CV *proto)
"cv_name"
Returns an SV containing the name of the CV, mainly for use in error
reporting. The CV may actually be a GV instead, in which case the
returned SV holds the GV's name. Anything other than a GV or CV is
treated as a string already holding the sub name, but this could
change in the future.
An SV may be passed as a second argument. If so, the name will be
assigned to it and it will be returned. Otherwise the returned SV
will be a new mortal.
If "flags" has the "CV_NAME_NOTQUAL" bit set, then the package name
will not be included. If the first argument is neither a CV nor a
GV, this flag is ignored (subject to change).
SV * cv_name(CV *cv, SV *sv, U32 flags)
"cv_undef"
Clear out all the active components of a CV. This can happen either
by an explicit "undef &foo", or by the reference count going to
zero. In the former case, we keep the "CvOUTSIDE" pointer, so that
any anonymous children can still follow the full lexical scope
chain.
void cv_undef(CV *cv)
"find_rundefsv"
Returns the global variable $_.
SV * find_rundefsv()
"get_op_descs"
"DEPRECATED!" It is planned to remove "get_op_descs" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Return a pointer to the array of all the descriptions of the various
OPs Given an opcode from the enum in opcodes.h, "PL_op_desc[opcode]"
returns a pointer to a C language string giving its description.
char ** get_op_descs()
"get_op_names"
"DEPRECATED!" It is planned to remove "get_op_names" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Return a pointer to the array of all the names of the various OPs
Given an opcode from the enum in opcodes.h, "PL_op_name[opcode]"
returns a pointer to a C language string giving its name.
char ** get_op_names()
"HAS_SKIP_LOCALE_INIT"
Described in perlembed.
"intro_my"
"Introduce" "my" variables to visible status. This is called during
parsing at the end of each statement to make lexical variables
visible to subsequent statements.
U32 intro_my()
"load_module"
"load_module_nocontext"
These load the module whose name is pointed to by the string part of
"name". Note that the actual module name, not its filename, should
be given. Eg, "Foo::Bar" instead of "Foo/Bar.pm". ver, if specified
and not NULL, provides version semantics similar to "use Foo::Bar
VERSION". The optional trailing arguments can be used to specify
arguments to the module's import() method, similar to "use Foo::Bar
VERSION LIST"; their precise handling depends on the flags. The
flags argument is a bitwise-ORed collection of any of
"PERL_LOADMOD_DENY", "PERL_LOADMOD_NOIMPORT", or
"PERL_LOADMOD_IMPORT_OPS" (or 0 for no flags).
If "PERL_LOADMOD_NOIMPORT" is set, the module is loaded as if with
an empty import list, as in "use Foo::Bar ()"; this is the only
circumstance in which the trailing optional arguments may be omitted
entirely. Otherwise, if "PERL_LOADMOD_IMPORT_OPS" is set, the
trailing arguments must consist of exactly one "OP*", containing the
op tree that produces the relevant import arguments. Otherwise, the
trailing arguments must all be "SV*" values that will be used as
import arguments; and the list must be terminated with "(SV*) NULL".
If neither "PERL_LOADMOD_NOIMPORT" nor "PERL_LOADMOD_IMPORT_OPS" is
set, the trailing "NULL" pointer is needed even if no import
arguments are desired. The reference count for each specified "SV*"
argument is decremented. In addition, the "name" argument is
modified.
If "PERL_LOADMOD_DENY" is set, the module is loaded as if with "no"
rather than "use".
"load_module" and "load_module_nocontext" have the same apparent
signature, but the former hides the fact that it is accessing a
thread context parameter. So use the latter when you get a
compilation error about "pTHX".
void load_module (U32 flags, SV *name, SV *ver, ...)
void load_module_nocontext(U32 flags, SV *name, SV *ver, ...)
"my_exit"
A wrapper for the C library exit(3), honoring what "PL_exit_flags"
in perlapi say to do.
void my_exit(U32 status)
"my_failure_exit"
Exit the running Perl process with an error.
On non-VMS platforms, this is essentially equivalent to ""my_exit"",
using "errno", but forces an en error code of 255 if "errno" is 0.
On VMS, it takes care to set the appropriate severity bits in the
exit status.
void my_failure_exit()
"my_strlcat"
The C library "strlcat" if available, or a Perl implementation of
it. This operates on C "NUL"-terminated strings.
my_strlcat() appends string "src" to the end of "dst". It will
append at most "size - strlen(dst) - 1" bytes. It will then
"NUL"-terminate, unless "size" is 0 or the original "dst" string was
longer than "size" (in practice this should not happen as it means
that either "size" is incorrect or that "dst" is not a proper
"NUL"-terminated string).
Note that "size" is the full size of the destination buffer and the
result is guaranteed to be "NUL"-terminated if there is room. Note
that room for the "NUL" should be included in "size".
The return value is the total length that "dst" would have if "size"
is sufficiently large. Thus it is the initial length of "dst" plus
the length of "src". If "size" is smaller than the return, the
excess was not appended.
Size_t my_strlcat(char *dst, const char *src, Size_t size)
"my_strlcpy"
The C library "strlcpy" if available, or a Perl implementation of
it. This operates on C "NUL"-terminated strings.
my_strlcpy() copies up to "size - 1" bytes from the string "src" to
"dst", "NUL"-terminating the result if "size" is not 0.
The return value is the total length "src" would be if the copy
completely succeeded. If it is larger than "size", the excess was
not copied.
Size_t my_strlcpy(char *dst, const char *src, Size_t size)
"newPADNAMELIST"
NOTE: "newPADNAMELIST" is experimental and may change or be removed
without notice.
Creates a new pad name list. "max" is the highest index for which
space is allocated.
PADNAMELIST * newPADNAMELIST(size_t max)
"newPADNAMEouter"
NOTE: "newPADNAMEouter" is experimental and may change or be removed
without notice.
Constructs and returns a new pad name. Only use this function for
names that refer to outer lexicals. (See also "newPADNAMEpvn".)
"outer" is the outer pad name that this one mirrors. The returned
pad name has the "PADNAMEf_OUTER" flag already set.
PADNAME * newPADNAMEouter(PADNAME *outer)
"newPADNAMEpvn"
NOTE: "newPADNAMEpvn" is experimental and may change or be removed
without notice.
Constructs and returns a new pad name. "s" must be a UTF-8 string.
Do not use this for pad names that point to outer lexicals. See
"newPADNAMEouter".
PADNAME * newPADNAMEpvn(const char *s, STRLEN len)
"nothreadhook"
Stub that provides thread hook for perl_destruct when there are no
threads.
int nothreadhook()
"pad_add_anon"
Allocates a place in the currently-compiling pad (via "pad_alloc")
for an anonymous function that is lexically scoped inside the
currently-compiling function. The function "func" is linked into
the pad, and its "CvOUTSIDE" link to the outer scope is weakened to
avoid a reference loop.
One reference count is stolen, so you may need to do
SvREFCNT_inc(func).
"optype" should be an opcode indicating the type of operation that
the pad entry is to support. This doesn't affect operational
semantics, but is used for debugging.
PADOFFSET pad_add_anon(CV *func, I32 optype)
"pad_add_name_pv"
Exactly like "pad_add_name_pvn", but takes a nul-terminated string
instead of a string/length pair.
PADOFFSET pad_add_name_pv(const char *name, const U32 flags,
HV *typestash, HV *ourstash)
"pad_add_name_pvn"
Allocates a place in the currently-compiling pad for a named lexical
variable. Stores the name and other metadata in the name part of
the pad, and makes preparations to manage the variable's lexical
scoping. Returns the offset of the allocated pad slot.
"namepv"/"namelen" specify the variable's name in UTF-8, including
leading sigil. If "typestash" is non-null, the name is for a typed
lexical, and this identifies the type. If "ourstash" is non-null,
it's a lexical reference to a package variable, and this identifies
the package. The following flags can be OR'ed together:
padadd_OUR redundantly specifies if it's a package var
padadd_STATE variable will retain value persistently
padadd_NO_DUP_CHECK skip check for lexical shadowing
padadd_FIELD specifies that the lexical is a field for a class
PADOFFSET pad_add_name_pvn(const char *namepv, STRLEN namelen,
U32 flags, HV *typestash,
HV *ourstash)
"pad_add_name_sv"
Exactly like "pad_add_name_pvn", but takes the name string in the
form of an SV instead of a string/length pair.
PADOFFSET pad_add_name_sv(SV *name, U32 flags, HV *typestash,
HV *ourstash)
"pad_alloc"
NOTE: "pad_alloc" is experimental and may change or be removed
without notice.
Allocates a place in the currently-compiling pad, returning the
offset of the allocated pad slot. No name is initially attached to
the pad slot. "tmptype" is a set of flags indicating the kind of
pad entry required, which will be set in the value SV for the
allocated pad entry:
SVs_PADMY named lexical variable ("my", "our", "state")
SVs_PADTMP unnamed temporary store
SVf_READONLY constant shared between recursion levels
"SVf_READONLY" has been supported here only since perl 5.20. To
work with earlier versions as well, use "SVf_READONLY|SVs_PADTMP".
"SVf_READONLY" does not cause the SV in the pad slot to be marked
read-only, but simply tells "pad_alloc" that it will be made read-
only (by the caller), or at least should be treated as such.
"optype" should be an opcode indicating the type of operation that
the pad entry is to support. This doesn't affect operational
semantics, but is used for debugging.
PADOFFSET pad_alloc(I32 optype, U32 tmptype)
"pad_findmy_pv"
Exactly like "pad_findmy_pvn", but takes a nul-terminated string
instead of a string/length pair.
PADOFFSET pad_findmy_pv(const char *name, U32 flags)
"pad_findmy_pvn"
Given the name of a lexical variable, find its position in the
currently-compiling pad. "namepv"/"namelen" specify the variable's
name, including leading sigil. "flags" is reserved and must be
zero. If it is not in the current pad but appears in the pad of any
lexically enclosing scope, then a pseudo-entry for it is added in
the current pad. Returns the offset in the current pad, or
"NOT_IN_PAD" if no such lexical is in scope.
PADOFFSET pad_findmy_pvn(const char *namepv, STRLEN namelen,
U32 flags)
"pad_findmy_sv"
Exactly like "pad_findmy_pvn", but takes the name string in the form
of an SV instead of a string/length pair.
PADOFFSET pad_findmy_sv(SV *name, U32 flags)
"padnamelist_fetch"
NOTE: "padnamelist_fetch" is experimental and may change or be
removed without notice.
Fetches the pad name from the given index.
PADNAME * padnamelist_fetch(PADNAMELIST *pnl, SSize_t key)
"padnamelist_store"
NOTE: "padnamelist_store" is experimental and may change or be
removed without notice.
Stores the pad name (which may be null) at the given index, freeing
any existing pad name in that slot.
PADNAME ** padnamelist_store(PADNAMELIST *pnl, SSize_t key,
PADNAME *val)
"pad_tidy"
NOTE: "pad_tidy" is experimental and may change or be removed
without notice.
Tidy up a pad at the end of compilation of the code to which it
belongs. Jobs performed here are: remove most stuff from the pads
of anonsub prototypes; give it a @_; mark temporaries as such.
"type" indicates the kind of subroutine:
padtidy_SUB ordinary subroutine
padtidy_SUBCLONE prototype for lexical closure
padtidy_FORMAT format
void pad_tidy(padtidy_type type)
"perl_alloc"
Allocates a new Perl interpreter. See perlembed.
PerlInterpreter * perl_alloc()
"PERL_ASYNC_CHECK"
Described in perlinterp.
void PERL_ASYNC_CHECK()
"perl_clone"
Create and return a new interpreter by cloning the current one.
"perl_clone" takes these flags as parameters:
"CLONEf_COPY_STACKS" - is used to, well, copy the stacks also,
without it we only clone the data and zero the stacks, with it we
copy the stacks and the new perl interpreter is ready to run at the
exact same point as the previous one. The pseudo-fork code uses
"COPY_STACKS" while the threads->create doesn't.
"CLONEf_KEEP_PTR_TABLE" - "perl_clone" keeps a ptr_table with the
pointer of the old variable as a key and the new variable as a
value, this allows it to check if something has been cloned and not
clone it again, but rather just use the value and increase the
refcount. If "KEEP_PTR_TABLE" is not set then "perl_clone" will
kill the ptr_table using the function
"ptr_table_free(PL_ptr_table); PL_ptr_table = NULL;". A reason to
keep it around is if you want to dup some of your own variables
which are outside the graph that perl scans.
"CLONEf_CLONE_HOST" - This is a win32 thing, it is ignored on unix,
it tells perl's win32host code (which is c++) to clone itself, this
is needed on win32 if you want to run two threads at the same time,
if you just want to do some stuff in a separate perl interpreter and
then throw it away and return to the original one, you don't need to
do anything.
PerlInterpreter * perl_clone(PerlInterpreter *proto_perl,
UV flags)
"perl_construct"
Initializes a new Perl interpreter. See perlembed.
void perl_construct(PerlInterpreter *my_perl)
"perl_destruct"
Shuts down a Perl interpreter. See perlembed for a tutorial.
"my_perl" points to the Perl interpreter. It must have been
previously created through the use of "perl_alloc" and
"perl_construct". It may have been initialised through
"perl_parse", and may have been used through "perl_run" and other
means. This function should be called for any Perl interpreter that
has been constructed with "perl_construct", even if subsequent
operations on it failed, for example if "perl_parse" returned a non-
zero value.
If the interpreter's "PL_exit_flags" word has the
"PERL_EXIT_DESTRUCT_END" flag set, then this function will execute
code in "END" blocks before performing the rest of destruction. If
it is desired to make any use of the interpreter between
"perl_parse" and "perl_destruct" other than just calling "perl_run",
then this flag should be set early on. This matters if "perl_run"
will not be called, or if anything else will be done in addition to
calling "perl_run".
Returns a value be a suitable value to pass to the C library
function "exit" (or to return from "main"), to serve as an exit code
indicating the nature of the way the interpreter terminated. This
takes into account any failure of "perl_parse" and any early exit
from "perl_run". The exit code is of the type required by the host
operating system, so because of differing exit code conventions it
is not portable to interpret specific numeric values as having
specific meanings.
int perl_destruct(PerlInterpreter *my_perl)
"perl_free"
Releases a Perl interpreter. See perlembed.
void perl_free(PerlInterpreter *my_perl)
"PERL_GET_CONTEXT"
Described in perlguts.
"PerlInterpreter"
Described in perlembed.
"perl_parse"
Tells a Perl interpreter to parse a Perl script. This performs most
of the initialisation of a Perl interpreter. See perlembed for a
tutorial.
"my_perl" points to the Perl interpreter that is to parse the
script. It must have been previously created through the use of
"perl_alloc" and "perl_construct". "xsinit" points to a callback
function that will be called to set up the ability for this Perl
interpreter to load XS extensions, or may be null to perform no such
setup.
"argc" and "argv" supply a set of command-line arguments to the Perl
interpreter, as would normally be passed to the "main" function of a
C program. "argv[argc]" must be null. These arguments are where
the script to parse is specified, either by naming a script file or
by providing a script in a "-e" option. If $0 will be written to in
the Perl interpreter, then the argument strings must be in writable
memory, and so mustn't just be string constants.
"env" specifies a set of environment variables that will be used by
this Perl interpreter. If non-null, it must point to a null-
terminated array of environment strings. If null, the Perl
interpreter will use the environment supplied by the "environ"
global variable.
This function initialises the interpreter, and parses and compiles
the script specified by the command-line arguments. This includes
executing code in "BEGIN", "UNITCHECK", and "CHECK" blocks. It does
not execute "INIT" blocks or the main program.
Returns an integer of slightly tricky interpretation. The correct
use of the return value is as a truth value indicating whether there
was a failure in initialisation. If zero is returned, this
indicates that initialisation was successful, and it is safe to
proceed to call "perl_run" and make other use of it. If a non-zero
value is returned, this indicates some problem that means the
interpreter wants to terminate. The interpreter should not be just
abandoned upon such failure; the caller should proceed to shut the
interpreter down cleanly with "perl_destruct" and free it with
"perl_free".
For historical reasons, the non-zero return value also attempts to
be a suitable value to pass to the C library function "exit" (or to
return from "main"), to serve as an exit code indicating the nature
of the way initialisation terminated. However, this isn't portable,
due to differing exit code conventions. An attempt is made to
return an exit code of the type required by the host operating
system, but because it is constrained to be non-zero, it is not
necessarily possible to indicate every type of exit. It is only
reliable on Unix, where a zero exit code can be augmented with a set
bit that will be ignored. In any case, this function is not the
correct place to acquire an exit code: one should get that from
"perl_destruct".
int perl_parse(PerlInterpreter *my_perl, XSINIT_t xsinit,
int argc, char **argv, char **env)
"perl_run"
Tells a Perl interpreter to run its main program. See perlembed for
a tutorial.
"my_perl" points to the Perl interpreter. It must have been
previously created through the use of "perl_alloc" and
"perl_construct", and initialised through "perl_parse". This
function should not be called if "perl_parse" returned a non-zero
value, indicating a failure in initialisation or compilation.
This function executes code in "INIT" blocks, and then executes the
main program. The code to be executed is that established by the
prior call to "perl_parse". If the interpreter's "PL_exit_flags"
word does not have the "PERL_EXIT_DESTRUCT_END" flag set, then this
function will also execute code in "END" blocks. If it is desired
to make any further use of the interpreter after calling this
function, then "END" blocks should be postponed to "perl_destruct"
time by setting that flag.
Returns an integer of slightly tricky interpretation. The correct
use of the return value is as a truth value indicating whether the
program terminated non-locally. If zero is returned, this indicates
that the program ran to completion, and it is safe to make other use
of the interpreter (provided that the "PERL_EXIT_DESTRUCT_END" flag
was set as described above). If a non-zero value is returned, this
indicates that the interpreter wants to terminate early. The
interpreter should not be just abandoned because of this desire to
terminate; the caller should proceed to shut the interpreter down
cleanly with "perl_destruct" and free it with "perl_free".
For historical reasons, the non-zero return value also attempts to
be a suitable value to pass to the C library function "exit" (or to
return from "main"), to serve as an exit code indicating the nature
of the way the program terminated. However, this isn't portable,
due to differing exit code conventions. An attempt is made to
return an exit code of the type required by the host operating
system, but because it is constrained to be non-zero, it is not
necessarily possible to indicate every type of exit. It is only
reliable on Unix, where a zero exit code can be augmented with a set
bit that will be ignored. In any case, this function is not the
correct place to acquire an exit code: one should get that from
"perl_destruct".
int perl_run(PerlInterpreter *my_perl)
"PERL_SET_CONTEXT"
Described in perlguts.
void PERL_SET_CONTEXT(PerlInterpreter* i)
"PERL_SYS_INIT"
"PERL_SYS_INIT3"
These provide system-specific tune up of the C runtime environment
necessary to run Perl interpreters. Only one should be used, and it
should be called only once, before creating any Perl interpreters.
They differ in that "PERL_SYS_INIT3" also initializes "env".
void PERL_SYS_INIT (int *argc, char*** argv)
void PERL_SYS_INIT3(int *argc, char*** argv, char*** env)
"PERL_SYS_TERM"
Provides system-specific clean up of the C runtime environment after
running Perl interpreters. This should be called only once, after
freeing any remaining Perl interpreters.
void PERL_SYS_TERM()
"PL_exit_flags"
Contains flags controlling perl's behaviour on exit():
• "PERL_EXIT_DESTRUCT_END"
If set, END blocks are executed when the interpreter is
destroyed. This is normally set by perl itself after the
interpreter is constructed.
• "PERL_EXIT_ABORT"
Call abort() on exit. This is used internally by perl itself to
abort if exit is called while processing exit.
• "PERL_EXIT_WARN"
Warn on exit.
• "PERL_EXIT_EXPECTED"
Set by the "exit" in perlfunc operator.
U8 PL_exit_flags
"PL_origalen"
Described in perlembed.
"PL_perl_destruct_level"
This value may be set when embedding for full cleanup.
Possible values:
• 0 - none
• 1 - full
• 2 or greater - full with checks.
If $ENV{PERL_DESTRUCT_LEVEL} is set to an integer greater than the
value of "PL_perl_destruct_level" its value is used instead.
On threaded perls, each thread has an independent copy of this
variable; each initialized at creation time with the current value
of the creating thread's copy.
signed char PL_perl_destruct_level
"ptr_table_fetch"
Look for "sv" in the pointer-mapping table "tbl", returning its
value, or NULL if not found.
void * ptr_table_fetch(PTR_TBL_t * const tbl,
const void * const sv)
"ptr_table_free"
Clear and free a ptr table
void ptr_table_free(PTR_TBL_t * const tbl)
"ptr_table_new"
Create a new pointer-mapping table
PTR_TBL_t * ptr_table_new()
"ptr_table_split"
Double the hash bucket size of an existing ptr table
void ptr_table_split(PTR_TBL_t * const tbl)
"ptr_table_store"
Add a new entry to a pointer-mapping table "tbl". In hash terms,
"oldsv" is the key; Cnewsv> is the value.
The names "old" and "new" are specific to the core's typical use of
ptr_tables in thread cloning.
void ptr_table_store(PTR_TBL_t * const tbl,
const void * const oldsv,
void * const newsv)
"require_pv"
Tells Perl to "require" the file named by the string argument. It
is analogous to the Perl code "eval "require '$file'"". It's even
implemented that way; consider using load_module instead.
NOTE: the perl_require_pv() form is deprecated.
void require_pv(const char *pv)
"vload_module"
Like "load_module" but the arguments are an encapsulated argument
list.
void vload_module(U32 flags, SV *name, SV *ver, va_list *args)
Errno
"sv_string_from_errnum"
Generates the message string describing an OS error and returns it
as an SV. "errnum" must be a value that "errno" could take,
identifying the type of error.
If "tgtsv" is non-null then the string will be written into that SV
(overwriting existing content) and it will be returned. If "tgtsv"
is a null pointer then the string will be written into a new mortal
SV which will be returned.
The message will be taken from whatever locale would be used by $!,
and will be encoded in the SV in whatever manner would be used by
$!. The details of this process are subject to future change.
Currently, the message is taken from the C locale by default
(usually producing an English message), and from the currently
selected locale when in the scope of the "use locale" pragma. A
heuristic attempt is made to decode the message from the locale's
character encoding, but it will only be decoded as either UTF-8 or
ISO-8859-1. It is always correctly decoded in a UTF-8 locale,
usually in an ISO-8859-1 locale, and never in any other locale.
The SV is always returned containing an actual string, and with no
other OK bits set. Unlike $!, a message is even yielded for
"errnum" zero (meaning success), and if no useful message is
available then a useless string (currently empty) is returned.
SV * sv_string_from_errnum(int errnum, SV *tgtsv)
Exception Handling (simple) Macros
"dXCPT"
Set up necessary local variables for exception handling. See
"Exception Handling" in perlguts.
dXCPT;
"JMPENV_JUMP"
Described in perlinterp.
void JMPENV_JUMP(int v)
"JMPENV_PUSH"
Described in perlinterp.
void JMPENV_PUSH(int v)
"PL_restartop"
Described in perlinterp.
"XCPT_CATCH"
Introduces a catch block. See "Exception Handling" in perlguts.
"XCPT_RETHROW"
Rethrows a previously caught exception. See "Exception Handling" in
perlguts.
XCPT_RETHROW;
"XCPT_TRY_END"
Ends a try block. See "Exception Handling" in perlguts.
"XCPT_TRY_START"
Starts a try block. See "Exception Handling" in perlguts.
Filesystem configuration values
Also see "List of capability HAS_foo symbols".
"DIRNAMLEN"
This symbol, if defined, indicates to the C program that the length
of directory entry names is provided by a "d_namlen" field.
Otherwise you need to do strlen() on the "d_name" field.
"DOSUID"
This symbol, if defined, indicates that the C program should check
the script that it is executing for setuid/setgid bits, and attempt
to emulate setuid/setgid on systems that have disabled setuid #!
scripts because the kernel can't do it securely. It is up to the
package designer to make sure that this emulation is done securely.
Among other things, it should do an fstat on the script it just
opened to make sure it really is a setuid/setgid script, it should
make sure the arguments passed correspond exactly to the argument on
the #! line, and it should not trust any subprocesses to which it
must pass the filename rather than the file descriptor of the script
to be executed.
"EOF_NONBLOCK"
This symbol, if defined, indicates to the C program that a read() on
a non-blocking file descriptor will return 0 on "EOF", and not the
value held in "RD_NODATA" (-1 usually, in that case!).
"FCNTL_CAN_LOCK"
This symbol, if defined, indicates that fcntl() can be used for file
locking. Normally on Unix systems this is defined. It may be
undefined on "VMS".
"FFLUSH_ALL"
This symbol, if defined, tells that to flush all pending stdio
output one must loop through all the stdio file handles stored in an
array and fflush them. Note that if "fflushNULL" is defined,
fflushall will not even be probed for and will be left undefined.
"FFLUSH_NULL"
This symbol, if defined, tells that fflush(NULL) correctly flushes
all pending stdio output without side effects. In particular, on
some platforms calling fflush(NULL) *still* corrupts "STDIN" if it
is a pipe.
"FILE_base"
This macro is used to access the "_base" field (or equivalent) of
the "FILE" structure pointed to by its argument. This macro will
always be defined if "USE_STDIO_BASE" is defined.
void * FILE_base(FILE * f)
"FILE_bufsiz"
This macro is used to determine the number of bytes in the I/O
buffer pointed to by "_base" field (or equivalent) of the "FILE"
structure pointed to its argument. This macro will always be defined
if "USE_STDIO_BASE" is defined.
Size_t FILE_bufsiz(FILE *f)
"FILE_cnt"
This macro is used to access the "_cnt" field (or equivalent) of the
"FILE" structure pointed to by its argument. This macro will always
be defined if "USE_STDIO_PTR" is defined.
Size_t FILE_cnt(FILE * f)
"FILE_ptr"
This macro is used to access the "_ptr" field (or equivalent) of the
"FILE" structure pointed to by its argument. This macro will always
be defined if "USE_STDIO_PTR" is defined.
void * FILE_ptr(FILE * f)
"FLEXFILENAMES"
This symbol, if defined, indicates that the system supports
filenames longer than 14 characters.
"HAS_DIR_DD_FD"
This symbol, if defined, indicates that the "DIR"* dirstream
structure contains a member variable named "dd_fd".
"HAS_DUP2"
This symbol, if defined, indicates that the "dup2" routine is
available to duplicate file descriptors.
"HAS_DUP3"
This symbol, if defined, indicates that the "dup3" routine is
available to duplicate file descriptors.
"HAS_FAST_STDIO"
This symbol, if defined, indicates that the "fast stdio" is
available to manipulate the stdio buffers directly.
"HAS_FCHDIR"
This symbol, if defined, indicates that the "fchdir" routine is
available to change directory using a file descriptor.
"HAS_FCNTL"
This symbol, if defined, indicates to the C program that the fcntl()
function exists.
"HAS_FDCLOSE"
This symbol, if defined, indicates that the "fdclose" routine is
available to free a "FILE" structure without closing the underlying
file descriptor. This function appeared in "FreeBSD" 10.2.
"HAS_FDOPENDIR"
This symbol, if defined, indicates that the fdopendir() routine is
available to open directories using an opened file descriptor
already referring to that directory.
"HAS_FPATHCONF"
This symbol, if defined, indicates that pathconf() is available to
determine file-system related limits and options associated with a
given open file descriptor.
"HAS_FPOS64_T"
This symbol will be defined if the C compiler supports "fpos64_t".
"HAS_FSTATFS"
This symbol, if defined, indicates that the "fstatfs" routine is
available to stat filesystems by file descriptors.
"HAS_FSTATVFS"
This symbol, if defined, indicates that the "fstatvfs" routine is
available to stat filesystems by file descriptors.
"HAS_GETFSSTAT"
This symbol, if defined, indicates that the "getfsstat" routine is
available to stat filesystems in bulk.
"HAS_GETMNT"
This symbol, if defined, indicates that the "getmnt" routine is
available to get filesystem mount info by filename.
"HAS_GETMNTENT"
This symbol, if defined, indicates that the "getmntent" routine is
available to iterate through mounted file systems to get their info.
"HAS_HASMNTOPT"
This symbol, if defined, indicates that the "hasmntopt" routine is
available to query the mount options of file systems.
"HAS_LSEEK_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the lseek() function. Otherwise, it is up to the
program to supply one. A good guess is
extern off_t lseek(int, off_t, int);
"HAS_MKDIR"
This symbol, if defined, indicates that the "mkdir" routine is
available to create directories. Otherwise you should fork off a
new process to exec /bin/mkdir.
"HAS_OFF64_T"
This symbol will be defined if the C compiler supports "off64_t".
"HAS_OPENAT"
This symbol is defined if the openat() routine is available.
"HAS_OPEN3"
This manifest constant lets the C program know that the three
argument form of open(2) is available.
"HAS_POLL"
This symbol, if defined, indicates that the "poll" routine is
available to "poll" active file descriptors. Please check "I_POLL"
and "I_SYS_POLL" to know which header should be included as well.
"HAS_READDIR"
This symbol, if defined, indicates that the "readdir" routine is
available to read directory entries. You may have to include
dirent.h. See "I_DIRENT".
"HAS_READDIR64_R"
This symbol, if defined, indicates that the "readdir64_r" routine is
available to readdir64 re-entrantly.
"HAS_REWINDDIR"
This symbol, if defined, indicates that the "rewinddir" routine is
available. You may have to include dirent.h. See "I_DIRENT".
"HAS_RMDIR"
This symbol, if defined, indicates that the "rmdir" routine is
available to remove directories. Otherwise you should fork off a new
process to exec /bin/rmdir.
"HAS_SEEKDIR"
This symbol, if defined, indicates that the "seekdir" routine is
available. You may have to include dirent.h. See "I_DIRENT".
"HAS_SELECT"
This symbol, if defined, indicates that the "select" routine is
available to "select" active file descriptors. If the timeout field
is used, sys/time.h may need to be included.
"HAS_SETVBUF"
This symbol, if defined, indicates that the "setvbuf" routine is
available to change buffering on an open stdio stream. to a line-
buffered mode.
"HAS_STDIO_STREAM_ARRAY"
This symbol, if defined, tells that there is an array holding the
stdio streams.
"HAS_STRUCT_FS_DATA"
This symbol, if defined, indicates that the "struct fs_data" to do
statfs() is supported.
"HAS_STRUCT_STATFS"
This symbol, if defined, indicates that the "struct statfs" to do
statfs() is supported.
"HAS_STRUCT_STATFS_F_FLAGS"
This symbol, if defined, indicates that the "struct statfs" does
have the "f_flags" member containing the mount flags of the
filesystem containing the file. This kind of "struct statfs" is
coming from sys/mount.h ("BSD" 4.3), not from sys/statfs.h ("SYSV").
Older "BSDs" (like Ultrix) do not have statfs() and "struct statfs",
they have ustat() and getmnt() with "struct ustat" and "struct
fs_data".
"HAS_TELLDIR"
This symbol, if defined, indicates that the "telldir" routine is
available. You may have to include dirent.h. See "I_DIRENT".
"HAS_USTAT"
This symbol, if defined, indicates that the "ustat" system call is
available to query file system statistics by "dev_t".
"I_FCNTL"
This manifest constant tells the C program to include fcntl.h.
#ifdef I_FCNTL
#include <fcntl.h>
#endif
"I_SYS_DIR"
This symbol, if defined, indicates to the C program that it should
include sys/dir.h.
#ifdef I_SYS_DIR
#include <sys_dir.h>
#endif
"I_SYS_FILE"
This symbol, if defined, indicates to the C program that it should
include sys/file.h to get definition of "R_OK" and friends.
#ifdef I_SYS_FILE
#include <sys_file.h>
#endif
"I_SYS_NDIR"
This symbol, if defined, indicates to the C program that it should
include sys/ndir.h.
#ifdef I_SYS_NDIR
#include <sys_ndir.h>
#endif
"I_SYS_STATFS"
This symbol, if defined, indicates that sys/statfs.h exists.
#ifdef I_SYS_STATFS
#include <sys_statfs.h>
#endif
"LSEEKSIZE"
This symbol holds the number of bytes used by the "Off_t".
"RD_NODATA"
This symbol holds the return code from read() when no data is
present on the non-blocking file descriptor. Be careful! If
"EOF_NONBLOCK" is not defined, then you can't distinguish between no
data and "EOF" by issuing a read(). You'll have to find another way
to tell for sure!
"READDIR64_R_PROTO"
This symbol encodes the prototype of "readdir64_r". It is zero if
"d_readdir64_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_readdir64_r" is defined.
"STDCHAR"
This symbol is defined to be the type of char used in stdio.h. It
has the values "unsigned char" or "char".
"STDIO_CNT_LVALUE"
This symbol is defined if the "FILE_cnt" macro can be used as an
lvalue.
"STDIO_PTR_LVAL_NOCHANGE_CNT"
This symbol is defined if using the "FILE_ptr" macro as an lvalue to
increase the pointer by n leaves File_cnt(fp) unchanged.
"STDIO_PTR_LVAL_SETS_CNT"
This symbol is defined if using the "FILE_ptr" macro as an lvalue to
increase the pointer by n has the side effect of decreasing the
value of File_cnt(fp) by n.
"STDIO_PTR_LVALUE"
This symbol is defined if the "FILE_ptr" macro can be used as an
lvalue.
"STDIO_STREAM_ARRAY"
This symbol tells the name of the array holding the stdio streams.
Usual values include "_iob", "__iob", and "__sF".
"ST_INO_SIGN"
This symbol holds the signedness of "struct stat"'s "st_ino". 1 for
unsigned, -1 for signed.
"ST_INO_SIZE"
This variable contains the size of "struct stat"'s "st_ino" in
bytes.
"VAL_EAGAIN"
This symbol holds the errno error code set by read() when no data
was present on the non-blocking file descriptor.
"VAL_O_NONBLOCK"
This symbol is to be used during open() or fcntl(F_SETFL) to turn on
non-blocking I/O for the file descriptor. Note that there is no way
back, i.e. you cannot turn it blocking again this way. If you wish
to alternatively switch between blocking and non-blocking, use the
ioctl(FIOSNBIO) call instead, but that is not supported by all
devices.
"VOID_CLOSEDIR"
This symbol, if defined, indicates that the closedir() routine does
not return a value.
Floating point
Also "List of capability HAS_foo symbols" lists capabilities that arent
in this section. For example "HAS_ASINH", for the hyperbolic sine
function.
"CASTFLAGS"
This symbol contains flags that say what difficulties the compiler
has casting odd floating values to unsigned long:
0 = ok
1 = couldn't cast < 0
2 = couldn't cast >= 0x80000000
4 = couldn't cast in argument expression list
"CASTNEGFLOAT"
This symbol is defined if the C compiler can cast negative numbers
to unsigned longs, ints and shorts.
"DOUBLE_HAS_INF"
This symbol, if defined, indicates that the double has the infinity.
"DOUBLE_HAS_NAN"
This symbol, if defined, indicates that the double has the not-a-
number.
"DOUBLE_HAS_NEGATIVE_ZERO"
This symbol, if defined, indicates that the double has the
"negative_zero".
"DOUBLE_HAS_SUBNORMALS"
This symbol, if defined, indicates that the double has the
subnormals (denormals).
"DOUBLEINFBYTES"
This symbol, if defined, is a comma-separated list of hexadecimal
bytes for the double precision infinity.
"DOUBLEKIND"
"DOUBLEKIND" will be one of
"DOUBLE_IS_IEEE_754_32_BIT_LITTLE_ENDIAN"
"DOUBLE_IS_IEEE_754_32_BIT_BIG_ENDIAN"
"DOUBLE_IS_IEEE_754_64_BIT_LITTLE_ENDIAN"
"DOUBLE_IS_IEEE_754_64_BIT_BIG_ENDIAN"
"DOUBLE_IS_IEEE_754_128_BIT_LITTLE_ENDIAN"
"DOUBLE_IS_IEEE_754_128_BIT_BIG_ENDIAN"
"DOUBLE_IS_IEEE_754_64_BIT_MIXED_ENDIAN_LE_BE"
"DOUBLE_IS_IEEE_754_64_BIT_MIXED_ENDIAN_BE_LE"
"DOUBLE_IS_VAX_F_FLOAT" "DOUBLE_IS_VAX_D_FLOAT"
"DOUBLE_IS_VAX_G_FLOAT" "DOUBLE_IS_IBM_SINGLE_32_BIT"
"DOUBLE_IS_IBM_DOUBLE_64_BIT" "DOUBLE_IS_CRAY_SINGLE_64_BIT"
"DOUBLE_IS_UNKNOWN_FORMAT"
"DOUBLEMANTBITS"
This symbol, if defined, tells how many mantissa bits there are in
double precision floating point format. Note that this is usually
"DBL_MANT_DIG" minus one, since with the standard "IEEE" 754 formats
"DBL_MANT_DIG" includes the implicit bit, which doesn't really
exist.
"DOUBLENANBYTES"
This symbol, if defined, is a comma-separated list of hexadecimal
bytes (0xHH) for the double precision not-a-number.
"DOUBLESIZE"
This symbol contains the size of a double, so that the C
preprocessor can make decisions based on it.
"DOUBLE_STYLE_CRAY"
This symbol, if defined, indicates that the double is the 64-bit
"CRAY" mainframe format.
"DOUBLE_STYLE_IBM"
This symbol, if defined, indicates that the double is the 64-bit
"IBM" mainframe format.
"DOUBLE_STYLE_IEEE"
This symbol, if defined, indicates that the double is the 64-bit
"IEEE" 754.
"DOUBLE_STYLE_VAX"
This symbol, if defined, indicates that the double is the 64-bit
"VAX" format D or G.
"HAS_ATOLF"
This symbol, if defined, indicates that the "atolf" routine is
available to convert strings into long doubles.
"HAS_CLASS"
This symbol, if defined, indicates that the "class" routine is
available to classify doubles. Available for example in "AIX". The
returned values are defined in float.h and are:
FP_PLUS_NORM Positive normalized, nonzero
FP_MINUS_NORM Negative normalized, nonzero
FP_PLUS_DENORM Positive denormalized, nonzero
FP_MINUS_DENORM Negative denormalized, nonzero
FP_PLUS_ZERO +0.0
FP_MINUS_ZERO -0.0
FP_PLUS_INF +INF
FP_MINUS_INF -INF
FP_NANS Signaling Not a Number (NaNS)
FP_NANQ Quiet Not a Number (NaNQ)
"HAS_FINITE"
This symbol, if defined, indicates that the "finite" routine is
available to check whether a double is "finite" (non-infinity non-
NaN).
"HAS_FINITEL"
This symbol, if defined, indicates that the "finitel" routine is
available to check whether a long double is finite (non-infinity
non-NaN).
"HAS_FPCLASS"
This symbol, if defined, indicates that the "fpclass" routine is
available to classify doubles. Available for example in
Solaris/"SVR4". The returned values are defined in ieeefp.h and
are:
FP_SNAN signaling NaN
FP_QNAN quiet NaN
FP_NINF negative infinity
FP_PINF positive infinity
FP_NDENORM negative denormalized non-zero
FP_PDENORM positive denormalized non-zero
FP_NZERO negative zero
FP_PZERO positive zero
FP_NNORM negative normalized non-zero
FP_PNORM positive normalized non-zero
"HAS_FP_CLASS"
This symbol, if defined, indicates that the "fp_class" routine is
available to classify doubles. Available for example in Digital
"UNIX". The returned values are defined in math.h and are:
FP_SNAN Signaling NaN (Not-a-Number)
FP_QNAN Quiet NaN (Not-a-Number)
FP_POS_INF +infinity
FP_NEG_INF -infinity
FP_POS_NORM Positive normalized
FP_NEG_NORM Negative normalized
FP_POS_DENORM Positive denormalized
FP_NEG_DENORM Negative denormalized
FP_POS_ZERO +0.0 (positive zero)
FP_NEG_ZERO -0.0 (negative zero)
"HAS_FPCLASSIFY"
This symbol, if defined, indicates that the "fpclassify" routine is
available to classify doubles. Available for example in HP-UX. The
returned values are defined in math.h and are
FP_NORMAL Normalized
FP_ZERO Zero
FP_INFINITE Infinity
FP_SUBNORMAL Denormalized
FP_NAN NaN
"HAS_FP_CLASSIFY"
This symbol, if defined, indicates that the "fp_classify" routine is
available to classify doubles. The values are defined in math.h
FP_NORMAL Normalized
FP_ZERO Zero
FP_INFINITE Infinity
FP_SUBNORMAL Denormalized
FP_NAN NaN
"HAS_FPCLASSL"
This symbol, if defined, indicates that the "fpclassl" routine is
available to classify long doubles. Available for example in
"IRIX". The returned values are defined in ieeefp.h and are:
FP_SNAN signaling NaN
FP_QNAN quiet NaN
FP_NINF negative infinity
FP_PINF positive infinity
FP_NDENORM negative denormalized non-zero
FP_PDENORM positive denormalized non-zero
FP_NZERO negative zero
FP_PZERO positive zero
FP_NNORM negative normalized non-zero
FP_PNORM positive normalized non-zero
"HAS_FP_CLASSL"
This symbol, if defined, indicates that the "fp_classl" routine is
available to classify long doubles. Available for example in
Digital "UNIX". See for possible values "HAS_FP_CLASS".
"HAS_FPGETROUND"
This symbol, if defined, indicates that the "fpgetround" routine is
available to get the floating point rounding mode.
"HAS_FREXPL"
This symbol, if defined, indicates that the "frexpl" routine is
available to break a long double floating-point number into a
normalized fraction and an integral power of 2.
"HAS_ILOGB"
This symbol, if defined, indicates that the "ilogb" routine is
available to get integer exponent of a floating-point value.
"HAS_ISFINITE"
This symbol, if defined, indicates that the "isfinite" routine is
available to check whether a double is finite (non-infinity non-
NaN).
"HAS_ISFINITEL"
This symbol, if defined, indicates that the "isfinitel" routine is
available to check whether a long double is finite. (non-infinity
non-NaN).
"HAS_ISINF"
This symbol, if defined, indicates that the "isinf" routine is
available to check whether a double is an infinity.
"HAS_ISINFL"
This symbol, if defined, indicates that the "isinfl" routine is
available to check whether a long double is an infinity.
"HAS_ISNAN"
This symbol, if defined, indicates that the "isnan" routine is
available to check whether a double is a NaN.
"HAS_ISNANL"
This symbol, if defined, indicates that the "isnanl" routine is
available to check whether a long double is a NaN.
"HAS_ISNORMAL"
This symbol, if defined, indicates that the "isnormal" routine is
available to check whether a double is normal (non-zero normalized).
"HAS_J0L"
This symbol, if defined, indicates to the C program that the j0l()
function is available for Bessel functions of the first kind of the
order zero, for long doubles.
"HAS_J0"
This symbol, if defined, indicates to the C program that the j0()
function is available for Bessel functions of the first kind of the
order zero, for doubles.
"HAS_LDBL_DIG"
This symbol, if defined, indicates that this system's float.h or
limits.h defines the symbol "LDBL_DIG", which is the number of
significant digits in a long double precision number. Unlike for
"DBL_DIG", there's no good guess for "LDBL_DIG" if it is undefined.
"HAS_LDEXPL"
This symbol, if defined, indicates that the "ldexpl" routine is
available to shift a long double floating-point number by an
integral power of 2.
"HAS_LLRINT"
This symbol, if defined, indicates that the "llrint" routine is
available to return the long long value closest to a double
(according to the current rounding mode).
"HAS_LLRINTL"
This symbol, if defined, indicates that the "llrintl" routine is
available to return the long long value closest to a long double
(according to the current rounding mode).
"HAS_LLROUNDL"
This symbol, if defined, indicates that the "llroundl" routine is
available to return the nearest long long value away from zero of
the long double argument value.
"HAS_LONG_DOUBLE"
This symbol will be defined if the C compiler supports long doubles.
"HAS_LRINT"
This symbol, if defined, indicates that the "lrint" routine is
available to return the integral value closest to a double
(according to the current rounding mode).
"HAS_LRINTL"
This symbol, if defined, indicates that the "lrintl" routine is
available to return the integral value closest to a long double
(according to the current rounding mode).
"HAS_LROUNDL"
This symbol, if defined, indicates that the "lroundl" routine is
available to return the nearest integral value away from zero of the
long double argument value.
"HAS_MODFL"
This symbol, if defined, indicates that the "modfl" routine is
available to split a long double x into a fractional part f and an
integer part i such that |f| < 1.0 and (f + i) = x.
"HAS_NAN"
This symbol, if defined, indicates that the "nan" routine is
available to generate NaN.
"HAS_NEXTTOWARD"
This symbol, if defined, indicates that the "nexttoward" routine is
available to return the next machine representable long double from
x in direction y.
"HAS_REMAINDER"
This symbol, if defined, indicates that the "remainder" routine is
available to return the floating-point "remainder".
"HAS_SCALBN"
This symbol, if defined, indicates that the "scalbn" routine is
available to multiply floating-point number by integral power of
radix.
"HAS_SIGNBIT"
This symbol, if defined, indicates that the "signbit" routine is
available to check if the given number has the sign bit set. This
should include correct testing of -0.0. This will only be set if
the signbit() routine is safe to use with the NV type used
internally in perl. Users should call Perl_signbit(), which will be
#defined to the system's signbit() function or macro if this symbol
is defined.
"HAS_SQRTL"
This symbol, if defined, indicates that the "sqrtl" routine is
available to do long double square roots.
"HAS_STRTOD_L"
This symbol, if defined, indicates that the "strtod_l" routine is
available to convert strings to long doubles.
"HAS_STRTOLD"
This symbol, if defined, indicates that the "strtold" routine is
available to convert strings to long doubles.
"HAS_STRTOLD_L"
This symbol, if defined, indicates that the "strtold_l" routine is
available to convert strings to long doubles.
"HAS_TRUNC"
This symbol, if defined, indicates that the "trunc" routine is
available to round doubles towards zero.
"HAS_UNORDERED"
This symbol, if defined, indicates that the "unordered" routine is
available to check whether two doubles are "unordered" (effectively:
whether either of them is NaN)
"I_FENV"
This symbol, if defined, indicates to the C program that it should
include fenv.h to get the floating point environment definitions.
#ifdef I_FENV
#include <fenv.h>
#endif
"I_QUADMATH"
This symbol, if defined, indicates that quadmath.h exists and should
be included.
#ifdef I_QUADMATH
#include <quadmath.h>
#endif
"LONGDBLINFBYTES"
This symbol, if defined, is a comma-separated list of hexadecimal
bytes for the long double precision infinity.
"LONGDBLMANTBITS"
This symbol, if defined, tells how many mantissa bits there are in
long double precision floating point format. Note that this can be
"LDBL_MANT_DIG" minus one, since "LDBL_MANT_DIG" can include the
"IEEE" 754 implicit bit. The common x86-style 80-bit long double
does not have an implicit bit.
"LONGDBLNANBYTES"
This symbol, if defined, is a comma-separated list of hexadecimal
bytes (0xHH) for the long double precision not-a-number.
"LONG_DOUBLEKIND"
"LONG_DOUBLEKIND" will be one of "LONG_DOUBLE_IS_DOUBLE"
"LONG_DOUBLE_IS_IEEE_754_128_BIT_LITTLE_ENDIAN"
"LONG_DOUBLE_IS_IEEE_754_128_BIT_BIG_ENDIAN"
"LONG_DOUBLE_IS_X86_80_BIT_LITTLE_ENDIAN"
"LONG_DOUBLE_IS_X86_80_BIT_BIG_ENDIAN"
"LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LE_LE"
"LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BE_BE"
"LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LE_BE"
"LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BE_LE"
"LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LITTLE_ENDIAN"
"LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BIG_ENDIAN"
"LONG_DOUBLE_IS_VAX_H_FLOAT" "LONG_DOUBLE_IS_UNKNOWN_FORMAT" It is
only defined if the system supports long doubles.
"LONG_DOUBLESIZE"
This symbol contains the size of a long double, so that the C
preprocessor can make decisions based on it. It is only defined if
the system supports long doubles. Note that this is "sizeof(long
double)", which may include unused bytes.
"LONG_DOUBLE_STYLE_IEEE"
This symbol, if defined, indicates that the long double is any of
the "IEEE" 754 style long doubles: "LONG_DOUBLE_STYLE_IEEE_STD",
"LONG_DOUBLE_STYLE_IEEE_EXTENDED",
"LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLE".
"LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLE"
This symbol, if defined, indicates that the long double is the
128-bit double-double.
"LONG_DOUBLE_STYLE_IEEE_EXTENDED"
This symbol, if defined, indicates that the long double is the
80-bit "IEEE" 754. Note that despite the 'extended' this is less
than the 'std', since this is an extension of the double precision.
"LONG_DOUBLE_STYLE_IEEE_STD"
This symbol, if defined, indicates that the long double is the
128-bit "IEEE" 754.
"LONG_DOUBLE_STYLE_VAX"
This symbol, if defined, indicates that the long double is the
128-bit "VAX" format H.
"NV"
Described in perlguts.
"NVMANTBITS"
This symbol, if defined, tells how many mantissa bits (not including
implicit bit) there are in a Perl NV. This depends on which
floating point type was chosen.
"NV_OVERFLOWS_INTEGERS_AT"
This symbol gives the largest integer value that NVs can hold. This
value + 1.0 cannot be stored accurately. It is expressed as constant
floating point expression to reduce the chance of decimal/binary
conversion issues. If it can not be determined, the value 0 is
given.
"NV_PRESERVES_UV"
This symbol, if defined, indicates that a variable of type "NVTYPE"
can preserve all the bits of a variable of type "UVTYPE".
"NV_PRESERVES_UV_BITS"
This symbol contains the number of bits a variable of type "NVTYPE"
can preserve of a variable of type "UVTYPE".
"NVSIZE"
This symbol contains the sizeof(NV). Note that some floating point
formats have unused bytes. The most notable example is the x86*
80-bit extended precision which comes in byte sizes of 12 and 16
(for 32 and 64 bit platforms, respectively), but which only uses 10
bytes. Perl compiled with "-Duselongdouble" on x86* is like this.
"NVTYPE"
This symbol defines the C type used for Perl's NV.
"NV_ZERO_IS_ALLBITS_ZERO"
This symbol, if defined, indicates that a variable of type "NVTYPE"
stores 0.0 in memory as all bits zero.
General Configuration
This section contains configuration information not otherwise found in
the more specialized sections of this document. At the end is a list of
"#defines" whose name should be enough to tell you what they do, and a
list of #defines which tell you if you need to "#include" files to get
the corresponding functionality.
"ASCIIish"
A preprocessor symbol that is defined iff the system is an ASCII
platform; this symbol would not be defined on "EBCDIC" platforms.
#ifdef ASCIIish
"BYTEORDER"
This symbol holds the hexadecimal constant defined in byteorder, in
a UV, i.e. 0x1234 or 0x4321 or 0x12345678, etc... If the compiler
supports cross-compiling or multiple-architecture binaries, use
compiler-defined macros to determine the byte order.
"CHARBITS"
This symbol contains the size of a char, so that the C preprocessor
can make decisions based on it.
"DB_VERSION_MAJOR_CFG"
This symbol, if defined, defines the major version number of
Berkeley DB found in the db.h header when Perl was configured.
"DB_VERSION_MINOR_CFG"
This symbol, if defined, defines the minor version number of
Berkeley DB found in the db.h header when Perl was configured. For
DB version 1 this is always 0.
"DB_VERSION_PATCH_CFG"
This symbol, if defined, defines the patch version number of
Berkeley DB found in the db.h header when Perl was configured. For
DB version 1 this is always 0.
"DEFAULT_INC_EXCLUDES_DOT"
This symbol, if defined, removes the legacy default behavior of
including '.' at the end of @"INC".
"DLSYM_NEEDS_UNDERSCORE"
This symbol, if defined, indicates that we need to prepend an
underscore to the symbol name before calling dlsym(). This only
makes sense if you *have* dlsym, which we will presume is the case
if you're using dl_dlopen.xs.
"EBCDIC"
This symbol, if defined, indicates that this system uses "EBCDIC"
encoding.
"HAS_CSH"
This symbol, if defined, indicates that the C-shell exists.
"HAS_GETHOSTNAME"
This symbol, if defined, indicates that the C program may use the
gethostname() routine to derive the host name. See also "HAS_UNAME"
and "PHOSTNAME".
"HAS_GNULIBC"
This symbol, if defined, indicates to the C program that the "GNU" C
library is being used. A better check is to use the "__GLIBC__" and
"__GLIBC_MINOR__" symbols supplied with glibc.
"HAS_LGAMMA"
This symbol, if defined, indicates that the "lgamma" routine is
available to do the log gamma function. See also "HAS_TGAMMA" and
"HAS_LGAMMA_R".
"HAS_LGAMMA_R"
This symbol, if defined, indicates that the "lgamma_r" routine is
available to do the log gamma function without using the global
signgam variable.
"HAS_NON_INT_BITFIELDS"
This symbol, if defined, indicates that the C compiler accepts,
without error or warning, "struct bitfields" that are declared with
sizes other than plain 'int'; for example 'unsigned char' is
accepted.
"HAS_PRCTL_SET_NAME"
This symbol, if defined, indicates that the prctl routine is
available to set process title and supports "PR_SET_NAME".
"HAS_PROCSELFEXE"
This symbol is defined if "PROCSELFEXE_PATH" is a symlink to the
absolute pathname of the executing program.
"HAS_PSEUDOFORK"
This symbol, if defined, indicates that an emulation of the fork
routine is available.
"HAS_REGCOMP"
This symbol, if defined, indicates that the regcomp() routine is
available to do some regular pattern matching (usually on "POSIX".2
conforming systems).
"HAS_SETPGID"
This symbol, if defined, indicates that the "setpgid(pid, gpid)"
routine is available to set process group ID.
"HAS_SIGSETJMP"
This variable indicates to the C program that the sigsetjmp()
routine is available to save the calling process's registers and
stack environment for later use by siglongjmp(), and to optionally
save the process's signal mask. See "Sigjmp_buf", "Sigsetjmp", and
"Siglongjmp".
"HAS_STRUCT_CMSGHDR"
This symbol, if defined, indicates that the "struct cmsghdr" is
supported.
"HAS_STRUCT_MSGHDR"
This symbol, if defined, indicates that the "struct msghdr" is
supported.
"HAS_TGAMMA"
This symbol, if defined, indicates that the "tgamma" routine is
available to do the gamma function. See also "HAS_LGAMMA".
"HAS_UNAME"
This symbol, if defined, indicates that the C program may use the
uname() routine to derive the host name. See also "HAS_GETHOSTNAME"
and "PHOSTNAME".
"HAS_UNION_SEMUN"
This symbol, if defined, indicates that the "union semun" is defined
by including sys/sem.h. If not, the user code probably needs to
define it as:
union semun {
int val;
struct semid_ds *buf;
unsigned short *array;
}
"I_DIRENT"
This symbol, if defined, indicates to the C program that it should
include dirent.h. Using this symbol also triggers the definition of
the "Direntry_t" define which ends up being '"struct dirent"' or
'"struct direct"' depending on the availability of dirent.h.
#ifdef I_DIRENT
#include <dirent.h>
#endif
"I_POLL"
This symbol, if defined, indicates that poll.h exists and should be
included. (see also "HAS_POLL")
#ifdef I_POLL
#include <poll.h>
#endif
"I_SYS_RESOURCE"
This symbol, if defined, indicates to the C program that it should
include sys/resource.h.
#ifdef I_SYS_RESOURCE
#include <sys_resource.h>
#endif
"LIBM_LIB_VERSION"
This symbol, if defined, indicates that libm exports "_LIB_VERSION"
and that math.h defines the enum to manipulate it.
"NEED_VA_COPY"
This symbol, if defined, indicates that the system stores the
variable argument list datatype, "va_list", in a format that cannot
be copied by simple assignment, so that some other means must be
used when copying is required. As such systems vary in their
provision (or non-provision) of copying mechanisms, handy.h defines
a platform- independent macro, "Perl_va_copy(src, dst)", to do the
job.
"OSNAME"
This symbol contains the name of the operating system, as determined
by Configure. You shouldn't rely on it too much; the specific
feature tests from Configure are generally more reliable.
"OSVERS"
This symbol contains the version of the operating system, as
determined by Configure. You shouldn't rely on it too much; the
specific feature tests from Configure are generally more reliable.
"PERL_USE_GCC_BRACE_GROUPS"
This C pre-processor value, if defined, indicates that it is
permissible to use the GCC brace groups extension. However, use of
this extension is DISCOURAGED. Use a "static inline" function
instead.
The extension, of the form
({ statement ... })
turns the block consisting of statement ... into an expression with
a value, unlike plain C language blocks. This can present
optimization possibilities, BUT, unless you know for sure that this
will never be compiled without this extension being available and
not forbidden, you need to specify an alternative. Thus two code
paths have to be maintained, which can get out-of-sync. All these
issues are solved by using a "static inline" function instead.
Perl can be configured to not use this feature by passing the
parameter "-Accflags=-DPERL_GCC_BRACE_GROUPS_FORBIDDEN" to
Configure.
#ifdef PERL_USE_GCC_BRACE_GROUPS
"PHOSTNAME"
This symbol, if defined, indicates the command to feed to the
popen() routine to derive the host name. See also "HAS_GETHOSTNAME"
and "HAS_UNAME". Note that the command uses a fully qualified path,
so that it is safe even if used by a process with super-user
privileges.
"PROCSELFEXE_PATH"
If "HAS_PROCSELFEXE" is defined this symbol is the filename of the
symbolic link pointing to the absolute pathname of the executing
program.
"PTRSIZE"
This symbol contains the size of a pointer, so that the C
preprocessor can make decisions based on it. It will be
"sizeof(void *)" if the compiler supports (void *); otherwise it
will be "sizeof(char *)".
"RANDBITS"
This symbol indicates how many bits are produced by the function
used to generate normalized random numbers. Values include 15, 16,
31, and 48.
"SELECT_MIN_BITS"
This symbol holds the minimum number of bits operated by select.
That is, if you do "select(n, ...)", how many bits at least will be
cleared in the masks if some activity is detected. Usually this is
either n or 32*ceil(n/32), especially many little-endians do the
latter. This is only useful if you have select(), naturally.
"SETUID_SCRIPTS_ARE_SECURE_NOW"
This symbol, if defined, indicates that the bug that prevents setuid
scripts from being secure is not present in this kernel.
"ST_DEV_SIGN"
This symbol holds the signedness of "struct stat"'s "st_dev". 1 for
unsigned, -1 for signed.
"ST_DEV_SIZE"
This variable contains the size of "struct stat"'s "st_dev" in
bytes.
List of capability "HAS_foo" symbols
This is a list of those symbols that dont appear elsewhere in ths
document that indicate if the current platform has a certain capability.
Their names all begin with "HAS_". Only those symbols whose capability
is directly derived from the name are listed here. All others have
their meaning expanded out elsewhere in this document. This
(relatively) compact list is because we think that the expansion would
add little or no value and take up a lot of space (because there are so
many). If you think certain ones should be expanded, send email to
perl5-porters@perl.org <mailto:perl5-porters@perl.org>.
Each symbol here will be "#define"d if and only if the platform has the
capability. If you need more detail, see the corresponding entry in
config.h. For convenience, the list is split so that the ones that
indicate there is a reentrant version of a capability are listed
separately
"HAS_ACCEPT4", "HAS_ACCESS", "HAS_ACCESSX", "HAS_ACOSH",
"HAS_AINTL", "HAS_ALARM", "HAS_ASINH", "HAS_ATANH", "HAS_ATOLL",
"HAS_CBRT", "HAS_CHOWN", "HAS_CHROOT", "HAS_CHSIZE",
"HAS_CLEARENV", "HAS_COPYSIGN", "HAS_COPYSIGNL", "HAS_CRYPT",
"HAS_CTERMID", "HAS_CUSERID", "HAS_DIRFD", "HAS_DLADDR",
"HAS_DLERROR", "HAS_EACCESS", "HAS_ENDHOSTENT", "HAS_ENDNETENT",
"HAS_ENDPROTOENT", "HAS_ENDSERVENT", "HAS_ERF", "HAS_ERFC",
"HAS_EXPM1", "HAS_EXP2", "HAS_FCHMOD", "HAS_FCHMODAT",
"HAS_FCHOWN", "HAS_FDIM", "HAS_FD_SET", "HAS_FEGETROUND",
"HAS_FFS", "HAS_FFSL", "HAS_FGETPOS", "HAS_FLOCK", "HAS_FMA",
"HAS_FMAX", "HAS_FMIN", "HAS_FORK", "HAS_FSEEKO", "HAS_FSETPOS",
"HAS_FSYNC", "HAS_FTELLO", "HAS__FWALK", "HAS_GAI_STRERROR",
"HAS_GETADDRINFO", "HAS_GETCWD", "HAS_GETESPWNAM", "HAS_GETGROUPS",
"HAS_GETHOSTBYADDR", "HAS_GETHOSTBYNAME", "HAS_GETHOSTENT",
"HAS_GETLOGIN", "HAS_GETNAMEINFO", "HAS_GETNETBYADDR",
"HAS_GETNETBYNAME", "HAS_GETNETENT", "HAS_GETPAGESIZE",
"HAS_GETPGID", "HAS_GETPGRP", "HAS_GETPGRP2", "HAS_GETPPID",
"HAS_GETPRIORITY", "HAS_GETPROTOBYNAME", "HAS_GETPROTOBYNUMBER",
"HAS_GETPROTOENT", "HAS_GETPRPWNAM", "HAS_GETSERVBYNAME",
"HAS_GETSERVBYPORT", "HAS_GETSERVENT", "HAS_GETSPNAM", "HAS_HTONL",
"HAS_HTONS", "HAS_HYPOT", "HAS_ILOGBL", "HAS_INET_ATON",
"HAS_INETNTOP", "HAS_INETPTON", "HAS_IP_MREQ", "HAS_IP_MREQ_SOURCE",
"HAS_IPV6_MREQ", "HAS_IPV6_MREQ_SOURCE", "HAS_ISASCII",
"HAS_ISBLANK", "HAS_ISLESS", "HAS_KILLPG", "HAS_LCHOWN",
"HAS_LINK", "HAS_LINKAT", "HAS_LLROUND", "HAS_LOCKF", "HAS_LOGB",
"HAS_LOG1P", "HAS_LOG2", "HAS_LROUND", "HAS_LSTAT", "HAS_MADVISE",
"HAS_MBLEN", "HAS_MBRLEN", "HAS_MBRTOWC", "HAS_MBSTOWCS",
"HAS_MBTOWC", "HAS_MEMMEM", "HAS_MEMRCHR", "HAS_MKDTEMP",
"HAS_MKFIFO", "HAS_MKOSTEMP", "HAS_MKSTEMP", "HAS_MKSTEMPS",
"HAS_MMAP", "HAS_MPROTECT", "HAS_MSG", "HAS_MSYNC", "HAS_MUNMAP",
"HAS_NEARBYINT", "HAS_NEXTAFTER", "HAS_NICE", "HAS_NTOHL",
"HAS_NTOHS", "HAS_PATHCONF", "HAS_PAUSE", "HAS_PHOSTNAME",
"HAS_PIPE", "HAS_PIPE2", "HAS_PRCTL", "HAS_PTRDIFF_T",
"HAS_READLINK", "HAS_READV", "HAS_RECVMSG", "HAS_REMQUO",
"HAS_RENAME", "HAS_RENAMEAT", "HAS_RINT", "HAS_ROUND",
"HAS_SCALBNL", "HAS_SEM", "HAS_SENDMSG", "HAS_SETEGID",
"HAS_SETENV", "HAS_SETEUID", "HAS_SETGROUPS", "HAS_SETHOSTENT",
"HAS_SETLINEBUF", "HAS_SETNETENT", "HAS_SETPGRP", "HAS_SETPGRP2",
"HAS_SETPRIORITY", "HAS_SETPROCTITLE", "HAS_SETPROTOENT",
"HAS_SETREGID", "HAS_SETRESGID", "HAS_SETRESUID", "HAS_SETREUID",
"HAS_SETRGID", "HAS_SETRUID", "HAS_SETSERVENT", "HAS_SETSID",
"HAS_SHM", "HAS_SIGACTION", "HAS_SIGPROCMASK", "HAS_SIN6_SCOPE_ID",
"HAS_SNPRINTF", "HAS_STAT", "HAS_STRCOLL", "HAS_STRERROR_L",
"HAS_STRLCAT", "HAS_STRLCPY", "HAS_STRNLEN", "HAS_STRTOD",
"HAS_STRTOL", "HAS_STRTOLL", "HAS_STRTOQ", "HAS_STRTOUL",
"HAS_STRTOULL", "HAS_STRTOUQ", "HAS_STRXFRM", "HAS_STRXFRM_L",
"HAS_SYMLINK", "HAS_SYSCALL", "HAS_SYSCONF", "HAS_SYS_ERRLIST",
"HAS_SYSTEM", "HAS_TCGETPGRP", "HAS_TCSETPGRP", "HAS_TOWLOWER",
"HAS_TOWUPPER", "HAS_TRUNCATE", "HAS_TRUNCL", "HAS_UALARM",
"HAS_UMASK", "HAS_UNLINKAT", "HAS_UNSETENV", "HAS_VFORK",
"HAS_VSNPRINTF", "HAS_WAITPID", "HAS_WAIT4", "HAS_WCRTOMB",
"HAS_WCSCMP", "HAS_WCSTOMBS", "HAS_WCSXFRM", "HAS_WCTOMB",
"HAS_WRITEV"
And, the reentrant capabilities:
"HAS_CRYPT_R", "HAS_CTERMID_R", "HAS_DRAND48_R", "HAS_ENDHOSTENT_R",
"HAS_ENDNETENT_R", "HAS_ENDPROTOENT_R", "HAS_ENDSERVENT_R",
"HAS_GETGRGID_R", "HAS_GETGRNAM_R", "HAS_GETHOSTBYADDR_R",
"HAS_GETHOSTBYNAME_R", "HAS_GETHOSTENT_R", "HAS_GETLOGIN_R",
"HAS_GETNETBYADDR_R", "HAS_GETNETBYNAME_R", "HAS_GETNETENT_R",
"HAS_GETPROTOBYNAME_R", "HAS_GETPROTOBYNUMBER_R",
"HAS_GETPROTOENT_R", "HAS_GETPWNAM_R", "HAS_GETPWUID_R",
"HAS_GETSERVBYNAME_R", "HAS_GETSERVBYPORT_R", "HAS_GETSERVENT_R",
"HAS_GETSPNAM_R", "HAS_RANDOM_R", "HAS_READDIR_R",
"HAS_SETHOSTENT_R", "HAS_SETNETENT_R", "HAS_SETPROTOENT_R",
"HAS_SETSERVENT_R", "HAS_SRANDOM_R", "HAS_SRAND48_R",
"HAS_STRERROR_R", "HAS_TMPNAM_R", "HAS_TTYNAME_R"
Example usage:
#ifdef HAS_STRNLEN
use strnlen()
#else
use an alternative implementation
#endif
List of "#include" needed symbols
This list contains symbols that indicate if certain "#include" files are
present on the platform. If your code accesses the functionality that
one of these is for, you will need to "#include" it if the symbol on
this list is "#define"d. For more detail, see the corresponding entry
in config.h.
"I_ARPA_INET", "I_BFD", "I_CRYPT", "I_DBM", "I_DLFCN",
"I_EXECINFO", "I_FP", "I_FP_CLASS", "I_GDBM", "I_GDBMNDBM",
"I_GDBM_NDBM", "I_GRP", "I_IEEEFP", "I_INTTYPES", "I_LIBUTIL",
"I_MNTENT", "I_NDBM", "I_NETDB", "I_NET_ERRNO", "I_NETINET_IN",
"I_NETINET_TCP", "I_PROT", "I_PWD", "I_RPCSVC_DBM", "I_SGTTY",
"I_SHADOW", "I_STDBOOL", "I_STDINT", "I_SUNMATH", "I_SYS_ACCESS",
"I_SYS_IOCTL", "I_SYSLOG", "I_SYSMODE", "I_SYS_MOUNT",
"I_SYS_PARAM", "I_SYS_POLL", "I_SYS_SECURITY", "I_SYS_SELECT",
"I_SYS_STAT", "I_SYS_STATVFS", "I_SYS_SYSCALL", "I_SYS_TIME",
"I_SYS_TIME_KERNEL", "I_SYS_TIMES", "I_SYS_TYPES", "I_SYSUIO",
"I_SYS_UN", "I_SYSUTSNAME", "I_SYS_VFS", "I_SYS_WAIT", "I_TERMIO",
"I_TERMIOS", "I_UNISTD", "I_USTAT", "I_VFORK", "I_WCHAR",
"I_WCTYPE"
Example usage:
#ifdef I_WCHAR
#include <wchar.h>
#endif
Global Variables
These variables are global to an entire process. They are shared
between all interpreters and all threads in a process. Any variables
not documented here may be changed or removed without notice, so don't
use them! If you feel you really do need to use an unlisted variable,
first send email to perl5-porters@perl.org
<mailto:perl5-porters@perl.org>. It may be that someone there will
point out a way to accomplish what you need without using an internal
variable. But if not, you should get a go-ahead to document and then
use the variable.
"PL_check"
Array, indexed by opcode, of functions that will be called for the
"check" phase of optree building during compilation of Perl code.
For most (but not all) types of op, once the op has been initially
built and populated with child ops it will be filtered through the
check function referenced by the appropriate element of this array.
The new op is passed in as the sole argument to the check function,
and the check function returns the completed op. The check function
may (as the name suggests) check the op for validity and signal
errors. It may also initialise or modify parts of the ops, or
perform more radical surgery such as adding or removing child ops,
or even throw the op away and return a different op in its place.
This array of function pointers is a convenient place to hook into
the compilation process. An XS module can put its own custom check
function in place of any of the standard ones, to influence the
compilation of a particular type of op. However, a custom check
function must never fully replace a standard check function (or even
a custom check function from another module). A module modifying
checking must instead wrap the preexisting check function. A custom
check function must be selective about when to apply its custom
behaviour. In the usual case where it decides not to do anything
special with an op, it must chain the preexisting op function.
Check functions are thus linked in a chain, with the core's base
checker at the end.
For thread safety, modules should not write directly to this array.
Instead, use the function "wrap_op_checker".
"PL_infix_plugin"
NOTE: "PL_infix_plugin" is experimental and may change or be removed
without notice.
NOTE: This API exists entirely for the purpose of making the CPAN
module "XS::Parse::Infix" work. It is not expected that additional
modules will make use of it; rather, that they should use
"XS::Parse::Infix" to provide parsing of new infix operators.
Function pointer, pointing at a function used to handle extended
infix operators. The function should be declared as
int infix_plugin_function(pTHX_
char *opname, STRLEN oplen,
struct Perl_custom_infix **infix_ptr)
The function is called from the tokenizer whenever a possible infix
operator is seen. "opname" points to the operator name in the
parser's input buffer, and "oplen" gives the maximum number of bytes
of it that should be consumed; it is not null-terminated. The
function is expected to examine the operator name and possibly other
state such as %^H, to determine whether it wants to handle the
operator name.
As compared to the single stage of "PL_keyword_plugin", parsing of
additional infix operators occurs in three separate stages. This is
because of the more complex interactions it has with the parser, to
ensure that operator precedence rules work correctly. These stages
are co-ordinated by the use of an additional information structure.
If the function wants to handle the infix operator, it must set the
variable pointed to by "infix_ptr" to the address of a structure
that provides this additional information about the subsequent
parsing stages. If it does not, it should make a call to the next
function in the chain.
This structure has the following definition:
struct Perl_custom_infix {
enum Perl_custom_infix_precedence prec;
void (*parse)(pTHX_ SV **opdata,
struct Perl_custom_infix *);
OP *(*build_op)(pTHX_ SV **opdata, OP *lhs, OP *rhs,
struct Perl_custom_infix *);
};
The function must then return an integer giving the number of bytes
consumed by the name of this operator. In the case of an operator
whose name is composed of identifier characters, this must be equal
to "oplen". In the case of an operator named by non-identifier
characters, this is permitted to be shorter than "oplen", and any
additional characters after it will not be claimed by the infix
operator but instead will be consumed by the tokenizer and parser as
normal.
If the optional "parse" function is provided, it is called
immediately by the parser to let the operator's definition consume
any additional syntax from the source code. This should not be used
for normal operand parsing, but it may be useful when implementing
things like parametric operators or meta-operators that consume more
syntax themselves. This function may use the variable pointed to by
"opdata" to provide an SV containing additional data to be passed
into the "build_op" function later on.
The information structure gives the operator precedence level in the
"prec" field. This is used to tell the parser how much of the
surrounding syntax before and after should be considered as operands
to the operator.
The tokenizer and parser will then continue to operate as normal
until enough additional input has been parsed to form both the left-
and right-hand side operands to the operator, according to the
precedence level. At this point the "build_op" function is called,
being passed the left- and right-hand operands as optree fragments.
It is expected to combine them into the resulting optree fragment,
which it should return.
After the "build_op" function has returned, if the variable pointed
to by "opdata" was set to a non-"NULL" value, it will then be
destroyed by calling SvREFCNT_dec().
For thread safety, modules should not set this variable directly.
Instead, use the function "wrap_infix_plugin".
However, that all said, the introductory note above still applies.
This variable is provided in core perl only for the benefit of the
"XS::Parse::Infix" module. That module acts as a central registry
for infix operators, automatically handling things like deparse
support and discovery/reflection, and these abilities only work
because it knows all the registered operators. Other modules should
not use this interpreter variable directly to implement them because
then those central features would no longer work properly.
Furthermore, it is likely that this (experimental) API will be
replaced in a future Perl version by a more complete API that fully
implements the central registry and other semantics currently
provided by "XS::Parse::Infix", once the module has had sufficient
experimental testing time. This current mechanism exists only as an
interim measure to get to that stage.
"PL_keyword_plugin"
NOTE: "PL_keyword_plugin" is experimental and may change or be
removed without notice.
Function pointer, pointing at a function used to handle extended
keywords. The function should be declared as
int keyword_plugin_function(pTHX_
char *keyword_ptr, STRLEN keyword_len,
OP **op_ptr)
The function is called from the tokeniser, whenever a possible
keyword is seen. "keyword_ptr" points at the word in the parser's
input buffer, and "keyword_len" gives its length; it is not null-
terminated. The function is expected to examine the word, and
possibly other state such as %^H, to decide whether it wants to
handle it as an extended keyword. If it does not, the function
should return "KEYWORD_PLUGIN_DECLINE", and the normal parser
process will continue.
If the function wants to handle the keyword, it first must parse
anything following the keyword that is part of the syntax introduced
by the keyword. See "Lexer interface" for details.
When a keyword is being handled, the plugin function must build a
tree of "OP" structures, representing the code that was parsed. The
root of the tree must be stored in *op_ptr. The function then
returns a constant indicating the syntactic role of the construct
that it has parsed: "KEYWORD_PLUGIN_STMT" if it is a complete
statement, or "KEYWORD_PLUGIN_EXPR" if it is an expression. Note
that a statement construct cannot be used inside an expression
(except via "do BLOCK" and similar), and an expression is not a
complete statement (it requires at least a terminating semicolon).
When a keyword is handled, the plugin function may also have
(compile-time) side effects. It may modify "%^H", define functions,
and so on. Typically, if side effects are the main purpose of a
handler, it does not wish to generate any ops to be included in the
normal compilation. In this case it is still required to supply an
op tree, but it suffices to generate a single null op.
That's how the *PL_keyword_plugin function needs to behave overall.
Conventionally, however, one does not completely replace the
existing handler function. Instead, take a copy of
"PL_keyword_plugin" before assigning your own function pointer to
it. Your handler function should look for keywords that it is
interested in and handle those. Where it is not interested, it
should call the saved plugin function, passing on the arguments it
received. Thus "PL_keyword_plugin" actually points at a chain of
handler functions, all of which have an opportunity to handle
keywords, and only the last function in the chain (built into the
Perl core) will normally return "KEYWORD_PLUGIN_DECLINE".
For thread safety, modules should not set this variable directly.
Instead, use the function "wrap_keyword_plugin".
"PL_phase"
A value that indicates the current Perl interpreter's phase.
Possible values include "PERL_PHASE_CONSTRUCT", "PERL_PHASE_START",
"PERL_PHASE_CHECK", "PERL_PHASE_INIT", "PERL_PHASE_RUN",
"PERL_PHASE_END", and "PERL_PHASE_DESTRUCT".
For example, the following determines whether the interpreter is in
global destruction:
if (PL_phase == PERL_PHASE_DESTRUCT) {
// we are in global destruction
}
"PL_phase" was introduced in Perl 5.14; in prior perls you can use
"PL_dirty" (boolean) to determine whether the interpreter is in
global destruction. (Use of "PL_dirty" is discouraged since 5.14.)
enum perl_phase PL_phase
GV Handling and Stashes
A GV is a structure which corresponds to a Perl typeglob, ie *foo. It
is a structure that holds a pointer to a scalar, an array, a hash etc,
corresponding to $foo, @foo, %foo.
GVs are usually found as values in stashes (symbol table hashes) where
Perl stores its global variables.
A stash is a hash that contains all variables that are defined within a
package. See "Stashes and Globs" in perlguts
"amagic_call"
Perform the overloaded (active magic) operation given by "method".
"method" is one of the values found in overload.h.
"flags" affects how the operation is performed, as follows:
"AMGf_noleft"
"left" is not to be used in this operation.
"AMGf_noright"
"right" is not to be used in this operation.
"AMGf_unary"
The operation is done only on just one operand.
"AMGf_assign"
The operation changes one of the operands, e.g., $x += 1
SV * amagic_call(SV *left, SV *right, int method, int dir)
"amagic_deref_call"
Perform "method" overloading dereferencing on "ref", returning the
dereferenced result. "method" must be one of the dereference
operations given in overload.h.
If overloading is inactive on "ref", returns "ref" itself.
SV * amagic_deref_call(SV *ref, int method)
"gv_add_by_type"
Make sure there is a slot of type "type" in the GV "gv".
GV * gv_add_by_type(GV *gv, svtype type)
"Gv_AMupdate"
Recalculates overload magic in the package given by "stash".
Returns:
1 on success and there is some overload
0 if there is no overload
-1 if some error occurred and it couldn't croak (because
"destructing" is true).
int Gv_AMupdate(HV *stash, bool destructing)
"gv_autoload_pv"
"gv_autoload_pvn"
"gv_autoload_sv"
These each search for an "AUTOLOAD" method, returning NULL if not
found, or else returning a pointer to its GV, while setting the
package $AUTOLOAD variable to "name" (fully qualified). Also, if
found and the GV's CV is an XSUB, the CV's PV will be set to "name",
and its stash will be set to the stash of the GV.
Searching is done in "MRO" order, as specified in ""gv_fetchmeth"",
beginning with "stash" if it isn't NULL.
The forms differ only in how "name" is specified.
In "gv_autoload_pv", "namepv" is a C language NUL-terminated string.
In "gv_autoload_pvn", "name" points to the first byte of the name,
and an additional parameter, "len", specifies its length in bytes.
Hence, *name may contain embedded-NUL characters.
In "gv_autoload_sv", *namesv is an SV, and the name is the PV
extracted from that using ""SvPV"". If the SV is marked as being in
UTF-8, the extracted PV will also be.
GV * gv_autoload_pv (HV *stash, const char *namepv, U32 flags)
GV * gv_autoload_pvn(HV *stash, const char *name, STRLEN len,
U32 flags)
GV * gv_autoload_sv (HV *stash, SV *namesv, U32 flags)
"gv_autoload4"
Equivalent to "gv_autoload_pvn".
GV * gv_autoload4(HV *stash, const char *name, STRLEN len,
I32 method)
"GvAV"
Return the AV from the GV.
AV* GvAV(GV* gv)
"gv_AVadd"
"gv_HVadd"
"gv_IOadd"
"gv_SVadd"
Make sure there is a slot of the given type (AV, HV, IO, SV) in the
GV "gv".
GV * gv_AVadd(GV *gv)
"gv_const_sv"
If "gv" is a typeglob whose subroutine entry is a constant sub
eligible for inlining, or "gv" is a placeholder reference that would
be promoted to such a typeglob, then returns the value returned by
the sub. Otherwise, returns "NULL".
SV * gv_const_sv(GV *gv)
"GvCV"
Return the CV from the GV.
CV* GvCV(GV* gv)
"gv_efullname3"
"gv_efullname4"
"gv_fullname3"
"gv_fullname4"
Place the full package name of "gv" into "sv". The "gv_e*" forms
return instead the effective package name (see "HvENAME").
If "prefix" is non-NULL, it is considered to be a C language NUL-
terminated string, and the stored name will be prefaced with it.
The other difference between the functions is that the *4 forms have
an extra parameter, "keepmain". If "true" an initial "main::" in
the name is kept; if "false" it is stripped. With the *3 forms, it
is always kept.
void gv_efullname3(SV *sv, const GV *gv, const char *prefix)
void gv_efullname4(SV *sv, const GV *gv, const char *prefix,
bool keepmain)
void gv_fullname3 (SV *sv, const GV *gv, const char *prefix)
void gv_fullname4 (SV *sv, const GV *gv, const char *prefix,
bool keepmain)
"gv_fetchfile"
"gv_fetchfile_flags"
These return the debugger glob for the file (compiled by Perl) whose
name is given by the "name" parameter.
There are currently exactly two differences between these functions.
The "name" parameter to "gv_fetchfile" is a C string, meaning it is
"NUL"-terminated; whereas the "name" parameter to
"gv_fetchfile_flags" is a Perl string, whose length (in bytes) is
passed in via the "namelen" parameter This means the name may
contain embedded "NUL" characters. "namelen" doesn't exist in plain
"gv_fetchfile").
The other difference is that "gv_fetchfile_flags" has an extra
"flags" parameter, which is currently completely ignored, but allows
for possible future extensions.
GV * gv_fetchfile (const char *name)
GV * gv_fetchfile_flags(const char * const name,
const STRLEN len, const U32 flags)
"gv_fetchmeth"
"gv_fetchmeth_pv"
"gv_fetchmeth_pvn"
"gv_fetchmeth_sv"
These each look for a glob with name "name", containing a defined
subroutine, returning the GV of that glob if found, or "NULL" if
not.
"stash" is always searched (first), unless it is "NULL".
If "stash" is NULL, or was searched but nothing was found in it, and
the "GV_SUPER" bit is set in "flags", stashes accessible via @ISA
are searched next. Searching is conducted according to "MRO" order.
Finally, if no matches were found so far, and the "GV_NOUNIVERSAL"
flag in "flags" is not set, "UNIVERSAL::" is searched.
The argument "level" should be either 0 or -1. If -1, the function
will return without any side effects or caching. If 0, the function
makes sure there is a glob named "name" in "stash", creating one if
necessary. The subroutine slot in the glob will be set to any
subroutine found in the "stash" and "SUPER::" search, hence caching
any "SUPER::" result. Note that subroutines found in "UNIVERSAL::"
are not cached.
The GV returned from these may be a method cache entry, which is not
visible to Perl code. So when calling "call_sv", you should not use
the GV directly; instead, you should use the method's CV, which can
be obtained from the GV with the "GvCV" macro.
The only other significant value for "flags" is "SVf_UTF8",
indicating that "name" is to be treated as being encoded in UTF-8.
Plain "gv_fetchmeth" lacks a "flags" parameter, hence always
searches in "stash", then "UNIVERSAL::", and "name" is never UTF-8.
Otherwise it is exactly like "gv_fetchmeth_pvn".
The other forms do have a "flags" parameter, and differ only in how
the glob name is specified.
In "gv_fetchmeth_pv", "name" is a C language NUL-terminated string.
In "gv_fetchmeth_pvn", "name" points to the first byte of the name,
and an additional parameter, "len", specifies its length in bytes.
Hence, the name may contain embedded-NUL characters.
In "gv_fetchmeth_sv", *name is an SV, and the name is the PV
extracted from that, using ""SvPV"". If the SV is marked as being
in UTF-8, the extracted PV will also be.
GV * gv_fetchmeth (HV *stash, const char *name, STRLEN len,
I32 level)
GV * gv_fetchmeth_pv (HV *stash, const char *name, I32 level,
U32 flags)
GV * gv_fetchmeth_pvn(HV *stash, const char *name, STRLEN len,
I32 level, U32 flags)
GV * gv_fetchmeth_sv (HV *stash, SV *namesv, I32 level,
U32 flags)
"gv_fetchmeth_autoload"
This is the old form of "gv_fetchmeth_pvn_autoload", which has no
flags parameter.
GV * gv_fetchmeth_autoload(HV *stash, const char *name,
STRLEN len, I32 level)
"gv_fetchmethod"
See "gv_fetchmethod_autoload".
GV * gv_fetchmethod(HV *stash, const char *name)
"gv_fetchmethod_autoload"
Returns the glob which contains the subroutine to call to invoke the
method on the "stash". In fact in the presence of autoloading this
may be the glob for "AUTOLOAD". In this case the corresponding
variable $AUTOLOAD is already setup.
The third parameter of "gv_fetchmethod_autoload" determines whether
AUTOLOAD lookup is performed if the given method is not present:
non-zero means yes, look for AUTOLOAD; zero means no, don't look for
AUTOLOAD. Calling "gv_fetchmethod" is equivalent to calling
"gv_fetchmethod_autoload" with a non-zero "autoload" parameter.
These functions grant "SUPER" token as a prefix of the method name.
Note that if you want to keep the returned glob for a long time, you
need to check for it being "AUTOLOAD", since at the later time the
call may load a different subroutine due to $AUTOLOAD changing its
value. Use the glob created as a side effect to do this.
These functions have the same side-effects as "gv_fetchmeth" with
"level==0". The warning against passing the GV returned by
"gv_fetchmeth" to "call_sv" applies equally to these functions.
GV * gv_fetchmethod_autoload(HV *stash, const char *name,
I32 autoload)
"gv_fetchmeth_pv_autoload"
Exactly like "gv_fetchmeth_pvn_autoload", but takes a nul-terminated
string instead of a string/length pair.
GV * gv_fetchmeth_pv_autoload(HV *stash, const char *name,
I32 level, U32 flags)
"gv_fetchmeth_pvn_autoload"
Same as gv_fetchmeth_pvn(), but looks for autoloaded subroutines
too. Returns a glob for the subroutine.
For an autoloaded subroutine without a GV, will create a GV even if
"level < 0". For an autoloaded subroutine without a stub, GvCV() of
the result may be zero.
Currently, the only significant value for "flags" is "SVf_UTF8".
GV * gv_fetchmeth_pvn_autoload(HV *stash, const char *name,
STRLEN len, I32 level, U32 flags)
"gv_fetchmeth_sv_autoload"
Exactly like "gv_fetchmeth_pvn_autoload", but takes the name string
in the form of an SV instead of a string/length pair.
GV * gv_fetchmeth_sv_autoload(HV *stash, SV *namesv, I32 level,
U32 flags)
"gv_fetchpv"
"gv_fetchpvn"
"gv_fetchpvn_flags"
"gv_fetchpvs"
"gv_fetchsv"
"gv_fetchsv_nomg"
These all return the GV of type "sv_type" whose name is given by the
inputs, or NULL if no GV of that name and type could be found. See
"Stashes and Globs" in perlguts.
The only differences are how the input name is specified, and if
'get' magic is normally used in getting that name.
Don't be fooled by the fact that only one form has "flags" in its
name. They all have a "flags" parameter in fact, and all the flag
bits have the same meanings for all
If any of the flags "GV_ADD", "GV_ADDMG", "GV_ADDWARN",
"GV_ADDMULTI", or "GV_NOINIT" is set, a GV is created if none
already exists for the input name and type. However, "GV_ADDMG"
will only do the creation for magical GV's. For all of these flags
except "GV_NOINIT", "gv_init_pvn" is called after the addition.
"GV_ADDWARN" is used when the caller expects that adding won't be
necessary because the symbol should already exist; but if not, add
it anyway, with a warning that it was unexpectedly absent. The
"GV_ADDMULTI" flag means to pretend that the GV has been seen before
(i.e., suppress "Used once" warnings).
The flag "GV_NOADD_NOINIT" causes "gv_init_pvn" not be to called if
the GV existed but isn't PVGV.
If the "SVf_UTF8" bit is set, the name is treated as being encoded
in UTF-8; otherwise the name won't be considered to be UTF-8 in the
"pv"-named forms, and the UTF-8ness of the underlying SVs will be
used in the "sv" forms.
If the flag "GV_NOTQUAL" is set, the caller warrants that the input
name is a plain symbol name, not qualified with a package, otherwise
the name is checked for being a qualified one.
In "gv_fetchpv", "nambeg" is a C string, NUL-terminated with no
intermediate NULs.
In "gv_fetchpvs", "name" is a literal C string, hence is enclosed in
double quotes.
"gv_fetchpvn" and "gv_fetchpvn_flags" are identical. In these,
<nambeg> is a Perl string whose byte length is given by "full_len",
and may contain embedded NULs.
In "gv_fetchsv" and "gv_fetchsv_nomg", the name is extracted from
the PV of the input "name" SV. The only difference between these
two forms is that 'get' magic is normally done on "name" in
"gv_fetchsv", and always skipped with "gv_fetchsv_nomg". Including
"GV_NO_SVGMAGIC" in the "flags" parameter to "gv_fetchsv" makes it
behave identically to "gv_fetchsv_nomg".
GV * gv_fetchpv (const char *nambeg, I32 flags,
const svtype sv_type)
GV * gv_fetchpvn (const char * nambeg, STRLEN full_len,
I32 flags, const svtype sv_type)
GV * gv_fetchpvn_flags(const char *name, STRLEN len, I32 flags,
const svtype sv_type)
GV * gv_fetchpvs ("name", I32 flags, const svtype sv_type)
GV * gv_fetchsv (SV *name, I32 flags, const svtype sv_type)
GV * gv_fetchsv_nomg (SV *name, I32 flags, const svtype sv_type)
"GvHV"
Return the HV from the GV.
HV* GvHV(GV* gv)
"gv_init"
The old form of gv_init_pvn(). It does not work with UTF-8 strings,
as it has no flags parameter. If the "multi" parameter is set, the
"GV_ADDMULTI" flag will be passed to gv_init_pvn().
void gv_init(GV *gv, HV *stash, const char *name, STRLEN len,
int multi)
"gv_init_pv"
Same as gv_init_pvn(), but takes a nul-terminated string for the
name instead of separate char * and length parameters.
void gv_init_pv(GV *gv, HV *stash, const char *name, U32 flags)
"gv_init_pvn"
Converts a scalar into a typeglob. This is an incoercible typeglob;
assigning a reference to it will assign to one of its slots, instead
of overwriting it as happens with typeglobs created by "SvSetSV".
Converting any scalar that is SvOK() may produce unpredictable
results and is reserved for perl's internal use.
"gv" is the scalar to be converted.
"stash" is the parent stash/package, if any.
"name" and "len" give the name. The name must be unqualified; that
is, it must not include the package name. If "gv" is a stash
element, it is the caller's responsibility to ensure that the name
passed to this function matches the name of the element. If it does
not match, perl's internal bookkeeping will get out of sync.
"flags" can be set to "SVf_UTF8" if "name" is a UTF-8 string, or the
return value of SvUTF8(sv). It can also take the "GV_ADDMULTI"
flag, which means to pretend that the GV has been seen before (i.e.,
suppress "Used once" warnings).
void gv_init_pvn(GV *gv, HV *stash, const char *name, STRLEN len,
U32 flags)
"gv_init_sv"
Same as gv_init_pvn(), but takes an SV * for the name instead of
separate char * and length parameters. "flags" is currently unused.
void gv_init_sv(GV *gv, HV *stash, SV *namesv, U32 flags)
"gv_name_set"
Set the name for GV "gv" to "name" which is "len" bytes long. Thus
it may contain embedded NUL characters.
If "flags" contains "SVf_UTF8", the name is treated as being encoded
in UTF-8; otherwise not.
void gv_name_set(GV *gv, const char *name, U32 len, U32 flags)
"gv_stashpv"
Returns a pointer to the stash for a specified package. Uses
"strlen" to determine the length of "name", then calls
gv_stashpvn().
HV * gv_stashpv(const char *name, I32 flags)
"gv_stashpvn"
Returns a pointer to the stash for a specified package. The
"namelen" parameter indicates the length of the "name", in bytes.
"flags" is passed to gv_fetchpvn_flags(), so if set to "GV_ADD" then
the package will be created if it does not already exist. If the
package does not exist and "flags" is 0 (or any other setting that
does not create packages) then "NULL" is returned.
Flags may be one of:
GV_ADD Create and initialize the package if doesn't
already exist
GV_NOADD_NOINIT Don't create the package,
GV_ADDMG GV_ADD iff the GV is magical
GV_NOINIT GV_ADD, but don't initialize
GV_NOEXPAND Don't expand SvOK() entries to PVGV
SVf_UTF8 The name is in UTF-8
The most important of which are probably "GV_ADD" and "SVf_UTF8".
Note, use of "gv_stashsv" instead of "gv_stashpvn" where possible is
strongly recommended for performance reasons.
HV * gv_stashpvn(const char *name, U32 namelen, I32 flags)
"gv_stashpvs"
Like "gv_stashpvn", but takes a literal string instead of a
string/length pair.
HV* gv_stashpvs("name", I32 create)
"gv_stashsv"
Returns a pointer to the stash for a specified package. See
"gv_stashpvn".
Note this interface is strongly preferred over "gv_stashpvn" for
performance reasons.
HV * gv_stashsv(SV *sv, I32 flags)
"GvSV"
Return the SV from the GV.
Prior to Perl v5.9.3, this would add a scalar if none existed.
Nowadays, use "GvSVn" for that, or compile perl with
"-DPERL_CREATE_GVSV". See perl5100delta.
SV* GvSV(GV* gv)
"GvSVn"
Like "GvSV", but creates an empty scalar if none already exists.
SV* GvSVn(GV* gv)
"newGVgen"
"newGVgen_flags"
Create a new, guaranteed to be unique, GV in the package given by
the NUL-terminated C language string "pack", and return a pointer to
it.
For "newGVgen" or if "flags" in "newGVgen_flags" is 0, "pack" is to
be considered to be encoded in Latin-1. The only other legal
"flags" value is "SVf_UTF8", which indicates "pack" is to be
considered to be encoded in UTF-8.
GV * newGVgen (const char *pack)
GV * newGVgen_flags(const char *pack, U32 flags)
"PL_curstash"
The stash for the package code will be compiled into.
On threaded perls, each thread has an independent copy of this
variable; each initialized at creation time with the current value
of the creating thread's copy.
HV* PL_curstash
"PL_defgv"
The GV representing *_. Useful for access to $_.
On threaded perls, each thread has an independent copy of this
variable; each initialized at creation time with the current value
of the creating thread's copy.
GV * PL_defgv
"PL_defoutgv"
See "setdefout".
"PL_defstash"
Described in perlguts.
"save_gp"
Saves the current GP of gv on the save stack to be restored on scope
exit.
If "empty" is true, replace the GP with a new GP.
If "empty" is false, mark "gv" with "GVf_INTRO" so the next
reference assigned is localized, which is how
" local *foo = $someref; " works.
void save_gp(GV *gv, I32 empty)
"setdefout"
Sets "PL_defoutgv", the default file handle for output, to the
passed in typeglob. As "PL_defoutgv" "owns" a reference on its
typeglob, the reference count of the passed in typeglob is increased
by one, and the reference count of the typeglob that "PL_defoutgv"
points to is decreased by one.
void setdefout(GV *gv)
Hook manipulation
These functions provide convenient and thread-safe means of manipulating
hook variables.
"rcpv_copy"
refcount increment a shared memory refcounted string, and when the
refcount goes to 0 free it using PerlMemShared_free().
It is the callers responsibility to ensure that the pv is the result
of a rcpv_new() call.
Returns the same pointer that was passed in.
new = rcpv_copy(pv);
char * rcpv_copy(char * const pv)
"rcpv_free"
refcount decrement a shared memory refcounted string, and when the
refcount goes to 0 free it using perlmemshared_free().
it is the callers responsibility to ensure that the pv is the result
of a rcpv_new() call.
Always returns NULL so it can be used like this:
thing = rcpv_free(thing);
char * rcpv_free(char * const pv)
"rcpv_new"
Create a new shared memory refcounted string with the requested
size, and with the requested initialization and a refcount of 1. The
actual space allocated will be 1 byte more than requested and
rcpv_new() will ensure that the extra byte is a null regardless of
any flags settings.
If the RCPVf_NO_COPY flag is set then the pv argument will be
ignored, otherwise the contents of the pv pointer will be copied
into the new buffer or if it is NULL the function will do nothing
and return NULL.
If the RCPVf_USE_STRLEN flag is set then the len argument is ignored
and recomputed using strlen(pv). It is an error to combine
RCPVf_USE_STRLEN and RCPVf_NO_COPY at the same time.
Under DEBUGGING rcpv_new() will assert() if it is asked to create a
0 length shared string unless the RCPVf_ALLOW_EMPTY flag is set.
The return value from the function is suitable for passing into
rcpv_copy() and rcpv_free(). To access the RCPV * from the returned
value use the RCPVx() macro. The 'len' member of the RCPV struct
stores the allocated length (including the extra byte), but the
RCPV_LEN() macro returns the requested length (not including the
extra byte).
Note that rcpv_new() does NOT use a hash table or anything like that
to dedupe inputs given the same text content. Each call with a non-
null pv parameter will produce a distinct pointer with its own
refcount regardless of the input content.
char * rcpv_new(const char * const pv, STRLEN len, U32 flags)
"wrap_op_checker"
Puts a C function into the chain of check functions for a specified
op type. This is the preferred way to manipulate the "PL_check"
array. "opcode" specifies which type of op is to be affected.
"new_checker" is a pointer to the C function that is to be added to
that opcode's check chain, and "old_checker_p" points to the storage
location where a pointer to the next function in the chain will be
stored. The value of "new_checker" is written into the "PL_check"
array, while the value previously stored there is written to
*old_checker_p.
"PL_check" is global to an entire process, and a module wishing to
hook op checking may find itself invoked more than once per process,
typically in different threads. To handle that situation, this
function is idempotent. The location *old_checker_p must initially
(once per process) contain a null pointer. A C variable of static
duration (declared at file scope, typically also marked "static" to
give it internal linkage) will be implicitly initialised
appropriately, if it does not have an explicit initialiser. This
function will only actually modify the check chain if it finds
*old_checker_p to be null. This function is also thread safe on the
small scale. It uses appropriate locking to avoid race conditions
in accessing "PL_check".
When this function is called, the function referenced by
"new_checker" must be ready to be called, except for *old_checker_p
being unfilled. In a threading situation, "new_checker" may be
called immediately, even before this function has returned.
*old_checker_p will always be appropriately set before "new_checker"
is called. If "new_checker" decides not to do anything special with
an op that it is given (which is the usual case for most uses of op
check hooking), it must chain the check function referenced by
*old_checker_p.
Taken all together, XS code to hook an op checker should typically
look something like this:
static Perl_check_t nxck_frob;
static OP *myck_frob(pTHX_ OP *op) {
...
op = nxck_frob(aTHX_ op);
...
return op;
}
BOOT:
wrap_op_checker(OP_FROB, myck_frob, &nxck_frob);
If you want to influence compilation of calls to a specific
subroutine, then use "cv_set_call_checker_flags" rather than hooking
checking of all "entersub" ops.
void wrap_op_checker(Optype opcode, Perl_check_t new_checker,
Perl_check_t *old_checker_p)
HV Handling
A HV structure represents a Perl hash. It consists mainly of an array
of pointers, each of which points to a linked list of HE structures.
The array is indexed by the hash function of the key, so each linked
list represents all the hash entries with the same hash value. Each HE
contains a pointer to the actual value, plus a pointer to a HEK
structure which holds the key and hash value.
"get_hv"
Returns the HV of the specified Perl hash. "flags" are passed to
"gv_fetchpv". If "GV_ADD" is set and the Perl variable does not
exist then it will be created. If "flags" is zero (ignoring
"SVf_UTF8") and the variable does not exist then "NULL" is returned.
NOTE: the perl_get_hv() form is deprecated.
HV * get_hv(const char *name, I32 flags)
"HE"
Described in perlguts.
"HEf_SVKEY"
This flag, used in the length slot of hash entries and magic
structures, specifies the structure contains an "SV*" pointer where
a "char*" pointer is to be expected. (For information only--not to
be used).
"HeHASH"
Returns the computed hash stored in the hash entry.
U32 HeHASH(HE* he)
"HeKEY"
Returns the actual pointer stored in the key slot of the hash entry.
The pointer may be either "char*" or "SV*", depending on the value
of HeKLEN(). Can be assigned to. The HePV() or HeSVKEY() macros
are usually preferable for finding the value of a key.
void* HeKEY(HE* he)
"HeKLEN"
If this is negative, and amounts to "HEf_SVKEY", it indicates the
entry holds an "SV*" key. Otherwise, holds the actual length of the
key. Can be assigned to. The HePV() macro is usually preferable
for finding key lengths.
STRLEN HeKLEN(HE* he)
"HePV"
Returns the key slot of the hash entry as a "char*" value, doing any
necessary dereferencing of possibly "SV*" keys. The length of the
string is placed in "len" (this is a macro, so do not use &len). If
you do not care about what the length of the key is, you may use the
global variable "PL_na", though this is rather less efficient than
using a local variable. Remember though, that hash keys in perl are
free to contain embedded nulls, so using strlen() or similar is not
a good way to find the length of hash keys. This is very similar to
the SvPV() macro described elsewhere in this document. See also
"HeUTF8".
If you are using "HePV" to get values to pass to newSVpvn() to
create a new SV, you should consider using "newSVhek(HeKEY_hek(he))"
as it is more efficient.
char* HePV(HE* he, STRLEN len)
"HeSVKEY"
Returns the key as an "SV*", or "NULL" if the hash entry does not
contain an "SV*" key.
SV* HeSVKEY(HE* he)
"HeSVKEY_force"
Returns the key as an "SV*". Will create and return a temporary
mortal "SV*" if the hash entry contains only a "char*" key.
SV* HeSVKEY_force(HE* he)
"HeSVKEY_set"
Sets the key to a given "SV*", taking care to set the appropriate
flags to indicate the presence of an "SV*" key, and returns the same
"SV*".
SV* HeSVKEY_set(HE* he, SV* sv)
"HeUTF8"
Returns whether the "char *" value returned by "HePV" is encoded in
UTF-8, doing any necessary dereferencing of possibly "SV*" keys.
The value returned will be 0 or non-0, not necessarily 1 (or even a
value with any low bits set), so do not blindly assign this to a
"bool" variable, as "bool" may be a typedef for "char".
U32 HeUTF8(HE* he)
"HeVAL"
Returns the value slot (type "SV*") stored in the hash entry. Can
be assigned to.
SV *foo= HeVAL(hv);
HeVAL(hv)= sv;
SV* HeVAL(HE* he)
"HV"
Described in perlguts.
"hv_assert"
Check that a hash is in an internally consistent state.
NOTE: "hv_assert" must be explicitly called as "Perl_hv_assert" with
an "aTHX_" parameter.
void Perl_hv_assert(pTHX_ HV *hv)
"hv_bucket_ratio"
NOTE: "hv_bucket_ratio" is experimental and may change or be removed
without notice.
If the hash is tied dispatches through to the SCALAR tied method,
otherwise if the hash contains no keys returns 0, otherwise returns
a mortal sv containing a string specifying the number of used
buckets, followed by a slash, followed by the number of available
buckets.
This function is expensive, it must scan all of the buckets to
determine which are used, and the count is NOT cached. In a large
hash this could be a lot of buckets.
SV * hv_bucket_ratio(HV *hv)
"hv_clear"
Frees all the elements of a hash, leaving it empty. The XS
equivalent of "%hash = ()". See also "hv_undef".
See "av_clear" for a note about the hash possibly being invalid on
return.
void hv_clear(HV *hv)
"hv_clear_placeholders"
Clears any placeholders from a hash. If a restricted hash has any
of its keys marked as readonly and the key is subsequently deleted,
the key is not actually deleted but is marked by assigning it a
value of &PL_sv_placeholder. This tags it so it will be ignored by
future operations such as iterating over the hash, but will still
allow the hash to have a value reassigned to the key at some future
point. This function clears any such placeholder keys from the
hash. See Hash::Util::lock_keys() for an example of its use.
void hv_clear_placeholders(HV *hv)
"hv_copy_hints_hv"
A specialised version of "newHVhv" for copying "%^H". "ohv" must be
a pointer to a hash (which may have "%^H" magic, but should be
generally non-magical), or "NULL" (interpreted as an empty hash).
The content of "ohv" is copied to a new hash, which has the
"%^H"-specific magic added to it. A pointer to the new hash is
returned.
HV * hv_copy_hints_hv(HV * const ohv)
"hv_delete"
"hv_deletes"
These delete a key/value pair in the hash. The value's SV is
removed from the hash, made mortal, and returned to the caller.
In "hv_deletes", the key must be a C language string literal,
enclosed in double quotes. It is never treated as being in UTF-8.
There is no length_parameter.
In "hv_delete", the absolute value of "klen" is the length of the
key. If "klen" is negative the key is assumed to be in
UTF-8-encoded Unicode.
In both, the "flags" value will normally be zero; if set to
"G_DISCARD" then "NULL" will be returned. "NULL" will also be
returned if the key is not found.
SV * hv_delete (HV *hv, const char *key, I32 klen, I32 flags)
SV * hv_deletes(HV *hv, "key", U32 flags)
"hv_delete_ent"
Deletes a key/value pair in the hash. The value SV is removed from
the hash, made mortal, and returned to the caller. The "flags"
value will normally be zero; if set to "G_DISCARD" then "NULL" will
be returned. "NULL" will also be returned if the key is not found.
"hash" can be a valid precomputed hash value, or 0 to ask for it to
be computed.
SV * hv_delete_ent(HV *hv, SV *keysv, I32 flags, U32 hash)
"HvENAME"
Returns the effective name of a stash, or NULL if there is none.
The effective name represents a location in the symbol table where
this stash resides. It is updated automatically when packages are
aliased or deleted. A stash that is no longer in the symbol table
has no effective name. This name is preferable to "HvNAME" for use
in MRO linearisations and isa caches.
char* HvENAME(HV* stash)
"HvENAMELEN"
Returns the length of the stash's effective name.
STRLEN HvENAMELEN(HV *stash)
"HvENAMEUTF8"
Returns true if the effective name is in UTF-8 encoding.
unsigned char HvENAMEUTF8(HV *stash)
"hv_exists"
"hv_existss"
These return a boolean indicating whether the specified hash key
exists.
In "hv_existss", the key must be a C language string literal,
enclosed in double quotes. It is never treated as being in UTF-8.
There is no length_parameter.
In "hv_exists", the absolute value of "klen" is the length of the
key. If "klen" is negative the key is assumed to be in
UTF-8-encoded Unicode.
bool hv_exists (HV *hv, const char *key, I32 klen)
bool hv_existss(HV *hv, "key")
"hv_exists_ent"
Returns a boolean indicating whether the specified hash key exists.
"hash" can be a valid precomputed hash value, or 0 to ask for it to
be computed.
bool hv_exists_ent(HV *hv, SV *keysv, U32 hash)
"hv_fetch"
"hv_fetchs"
These return the SV which corresponds to the specified key in the
hash.
In "hv_fetchs", the key must be a C language string literal,
enclosed in double quotes. It is never treated as being in UTF-8.
There is no length_parameter.
In "hv_fetch", the absolute value of "klen" is the length of the
key. If "klen" is negative the key is assumed to be in
UTF-8-encoded Unicode.
In both, if "lval" is set, then the fetch will be part of a store.
This means that if there is no value in the hash associated with the
given key, then one is created and a pointer to it is returned. The
"SV*" it points to can be assigned to. But always check that the
return value is non-null before dereferencing it to an "SV*".
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts
for more information on how to use this function on tied hashes.
SV ** hv_fetch (HV *hv, const char *key, I32 klen, I32 lval)
SV ** hv_fetchs(HV *hv, "key", I32 lval)
"hv_fetch_ent"
Returns the hash entry which corresponds to the specified key in the
hash. "hash" must be a valid precomputed hash number for the given
"key", or 0 if you want the function to compute it. IF "lval" is
set then the fetch will be part of a store. Make sure the return
value is non-null before accessing it. The return value when "hv"
is a tied hash is a pointer to a static location, so be sure to make
a copy of the structure if you need to store it somewhere.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts
for more information on how to use this function on tied hashes.
HE * hv_fetch_ent(HV *hv, SV *keysv, I32 lval, U32 hash)
"hv_fetchs"
Like "hv_fetch", but takes a literal string instead of a
string/length pair.
SV** hv_fetchs(HV* tb, "key", I32 lval)
"HvFILL"
Returns the number of hash buckets that happen to be in use.
As of perl 5.25 this function is used only for debugging purposes,
and the number of used hash buckets is not in any way cached, thus
this function can be costly to execute as it must iterate over all
the buckets in the hash.
STRLEN HvFILL(HV *const hv)
"HvHasAUX"
Returns true if the HV has a "struct xpvhv_aux" extension. Use this
to check whether it is valid to call HvAUX().
bool HvHasAUX(HV *const hv)
"hv_iterinit"
Prepares a starting point to traverse a hash table. Returns the
number of keys in the hash, including placeholders (i.e. the same as
HvTOTALKEYS(hv)). The return value is currently only meaningful for
hashes without tie magic.
NOTE: Before version 5.004_65, "hv_iterinit" used to return the
number of hash buckets that happen to be in use. If you still need
that esoteric value, you can get it through the macro HvFILL(hv).
I32 hv_iterinit(HV *hv)
"hv_iterkey"
Returns the key from the current position of the hash iterator. See
"hv_iterinit".
char * hv_iterkey(HE *entry, I32 *retlen)
"hv_iterkeysv"
Returns the key as an "SV*" from the current position of the hash
iterator. The return value will always be a mortal copy of the key.
Also see "hv_iterinit".
SV * hv_iterkeysv(HE *entry)
"hv_iternext"
Returns entries from a hash iterator. See "hv_iterinit".
You may call "hv_delete" or "hv_delete_ent" on the hash entry that
the iterator currently points to, without losing your place or
invalidating your iterator. Note that in this case the current
entry is deleted from the hash with your iterator holding the last
reference to it. Your iterator is flagged to free the entry on the
next call to "hv_iternext", so you must not discard your iterator
immediately else the entry will leak - call "hv_iternext" to trigger
the resource deallocation.
HE * hv_iternext(HV *hv)
"hv_iternext_flags"
NOTE: "hv_iternext_flags" is experimental and may change or be
removed without notice.
Returns entries from a hash iterator. See "hv_iterinit" and
"hv_iternext". The "flags" value will normally be zero; if
"HV_ITERNEXT_WANTPLACEHOLDERS" is set the placeholders keys (for
restricted hashes) will be returned in addition to normal keys. By
default placeholders are automatically skipped over. Currently a
placeholder is implemented with a value that is &PL_sv_placeholder.
Note that the implementation of placeholders and restricted hashes
may change, and the implementation currently is insufficiently
abstracted for any change to be tidy.
HE * hv_iternext_flags(HV *hv, I32 flags)
"hv_iternextsv"
Performs an "hv_iternext", "hv_iterkey", and "hv_iterval" in one
operation.
SV * hv_iternextsv(HV *hv, char **key, I32 *retlen)
"hv_iterval"
Returns the value from the current position of the hash iterator.
See "hv_iterkey".
SV * hv_iterval(HV *hv, HE *entry)
"hv_ksplit"
Attempt to grow the hash "hv" so it has at least "newmax" buckets
available. Perl chooses the actual number for its convenience.
This is the same as doing the following in Perl code:
keys %hv = newmax;
void hv_ksplit(HV *hv, IV newmax)
"hv_magic"
Adds magic to a hash. See "sv_magic".
void hv_magic(HV *hv, GV *gv, int how)
"HvNAME"
Returns the package name of a stash, or "NULL" if "stash" isn't a
stash. See "SvSTASH", "CvSTASH".
char* HvNAME(HV* stash)
"HvNAMELEN"
Returns the length of the stash's name.
Disfavored forms of HvNAME and HvNAMELEN; suppress mention of them
STRLEN HvNAMELEN(HV *stash)
"hv_name_set"
"hv_name_sets"
These each set the name of stash "hv" to the specified name.
They differ only in how the name is specified.
In "hv_name_sets", the name is a literal C string, enclosed in
double quotes.
In "hv_name_set", "name" points to the first byte of the name, and
an additional parameter, "len", specifies its length in bytes.
Hence, the name may contain embedded-NUL characters.
If "SVf_UTF8" is set in "flags", the name is treated as being in
UTF-8; otherwise not.
If "HV_NAME_SETALL" is set in "flags", both the name and the
effective name are set.
void hv_name_set (HV *hv, const char *name, U32 len, U32 flags)
void hv_name_sets(HV *hv, "name", U32 flags)
"HvNAMEUTF8"
Returns true if the name is in UTF-8 encoding.
unsigned char HvNAMEUTF8(HV *stash)
"hv_scalar"
Evaluates the hash in scalar context and returns the result.
When the hash is tied dispatches through to the SCALAR method,
otherwise returns a mortal SV containing the number of keys in the
hash.
Note, prior to 5.25 this function returned what is now returned by
the hv_bucket_ratio() function.
SV * hv_scalar(HV *hv)
"hv_store"
"hv_stores"
These each store SV "val" with the specified key in hash "hv",
returning NULL if the operation failed or if the value did not need
to be actually stored within the hash (as in the case of tied
hashes). Otherwise it can be dereferenced to get the original
"SV*".
They differ only in how the hash key is specified.
In "hv_stores", the key must be a C language string literal,
enclosed in double quotes. It is never treated as being in UTF-8.
There is no length_parameter.
In "hv_store", "key" is either NULL or points to the first byte of
the string specifying the key, and its length in bytes is given by
the absolute value of an additional parameter, "klen". A NULL key
indicates the key is to be treated as "undef", and "klen" is
ignored; otherwise the key string may contain embedded-NUL bytes.
If "klen" is negative, the string is treated as being encoded in
UTF-8; otherwise not.
"hv_store" has another extra parameter, "hash", a precomputed hash
of the key string, or zero if it has not been precomputed. This
parameter is omitted from "hv_stores", as it is computed
automatically at compile time.
If <hv> is NULL, NULL is returned and no action is taken.
If "val" is NULL, it is treated as being "undef"; otherwise the
caller is responsible for suitably incrementing the reference count
of "val" before the call, and decrementing it if the function
returned "NULL". Effectively a successful "hv_store" takes
ownership of one reference to "val". This is usually what you want;
a newly created SV has a reference count of one, so if all your code
does is create SVs then store them in a hash, "hv_store" will own
the only reference to the new SV, and your code doesn't need to do
anything further to tidy up.
"hv_store" is not implemented as a call to ""hv_store_ent"", and
does not create a temporary SV for the key, so if your key data is
not already in SV form then use "hv_store" in preference to
"hv_store_ent".
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts
for more information on how to use this function on tied hashes.
SV ** hv_store (HV *hv, const char *key, I32 klen, SV *val,
U32 hash)
SV ** hv_stores(HV *hv, "key", SV *val)
"hv_store_ent"
Stores "val" in a hash. The hash key is specified as "key". The
"hash" parameter is the precomputed hash value; if it is zero then
Perl will compute it. The return value is the new hash entry so
created. It will be "NULL" if the operation failed or if the value
did not need to be actually stored within the hash (as in the case
of tied hashes). Otherwise the contents of the return value can be
accessed using the "He?" macros described here. Note that the
caller is responsible for suitably incrementing the reference count
of "val" before the call, and decrementing it if the function
returned NULL. Effectively a successful "hv_store_ent" takes
ownership of one reference to "val". This is usually what you want;
a newly created SV has a reference count of one, so if all your code
does is create SVs then store them in a hash, "hv_store" will own
the only reference to the new SV, and your code doesn't need to do
anything further to tidy up. Note that "hv_store_ent" only reads
the "key"; unlike "val" it does not take ownership of it, so
maintaining the correct reference count on "key" is entirely the
caller's responsibility. The reason it does not take ownership, is
that "key" is not used after this function returns, and so can be
freed immediately. "hv_store" is not implemented as a call to
"hv_store_ent", and does not create a temporary SV for the key, so
if your key data is not already in SV form then use "hv_store" in
preference to "hv_store_ent".
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts
for more information on how to use this function on tied hashes.
HE * hv_store_ent(HV *hv, SV *key, SV *val, U32 hash)
"hv_undef"
Undefines the hash. The XS equivalent of undef(%hash).
As well as freeing all the elements of the hash (like hv_clear()),
this also frees any auxiliary data and storage associated with the
hash.
See "av_clear" for a note about the hash possibly being invalid on
return.
void hv_undef(HV *hv)
"newHV"
Creates a new HV. The reference count is set to 1.
HV * newHV()
"newHVhv"
The content of "ohv" is copied to a new hash. A pointer to the new
hash is returned.
HV * newHVhv(HV *hv)
"Nullhv"
"DEPRECATED!" It is planned to remove "Nullhv" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Null HV pointer.
(deprecated - use "(HV *)NULL" instead)
"PERL_HASH"
Described in perlguts.
void PERL_HASH(U32 hash, char *key, STRLEN klen)
"PL_modglobal"
"PL_modglobal" is a general purpose, interpreter global HV for use
by extensions that need to keep information on a per-interpreter
basis. In a pinch, it can also be used as a symbol table for
extensions to share data among each other. It is a good idea to use
keys prefixed by the package name of the extension that owns the
data.
On threaded perls, each thread has an independent copy of this
variable; each initialized at creation time with the current value
of the creating thread's copy.
HV* PL_modglobal
Input/Output
"do_close"
Close an I/O stream. This implements Perl ""close"" in perlfunc.
"gv" is the glob associated with the stream.
"is_explict" is "true" if this is an explicit close of the stream;
"false" if it is part of another operation, such as closing a pipe
(which involves implicitly closing both ends).
Returns "true" if successful; otherwise returns "false" and sets
"errno" to indicate the cause.
bool do_close(GV *gv, bool is_explicit)
"IoDIRP"
Described in perlguts.
DIR * IoDIRP(IO *io)
"IOf_FLUSH"
Described in perlguts.
"IoFLAGS"
Described in perlguts.
U8 IoFLAGS(IO *io)
"IOf_UNTAINT"
Described in perlguts.
"IoIFP"
Described in perlguts.
PerlIO * IoIFP(IO *io)
"IoOFP"
Described in perlguts.
PerlIO * IoOFP(IO *io)
"IoTYPE"
Described in perlguts.
char IoTYPE(IO *io)
"my_chsize"
The C library chsize(3) if available, or a Perl implementation of
it.
I32 my_chsize(int fd, Off_t length)
"my_dirfd"
The C library dirfd(3) if available, or a Perl implementation of it,
or die if not easily emulatable.
int my_dirfd(DIR *dir)
"my_pclose"
A wrapper for the C library pclose(3). Don't use the latter, as the
Perl version knows things that interact with the rest of the perl
interpreter.
I32 my_pclose(PerlIO *ptr)
"my_popen"
A wrapper for the C library popen(3). Don't use the latter, as the
Perl version knows things that interact with the rest of the perl
interpreter.
PerlIO * my_popen(const char *cmd, const char *mode)
"newIO"
Create a new IO, setting the reference count to 1.
IO * newIO()
"PERL_FLUSHALL_FOR_CHILD"
This defines a way to flush all output buffers. This may be a
performance issue, so we allow people to disable it. Also, if we
are using stdio, there are broken implementations of fflush(NULL)
out there, Solaris being the most prominent.
void PERL_FLUSHALL_FOR_CHILD
"PerlIO_apply_layers"
"PerlIO_binmode"
"PerlIO_canset_cnt"
"PerlIO_clearerr"
"PerlIO_close"
"PerlIO_debug"
"PerlIO_eof"
"PerlIO_error"
"PerlIO_exportFILE"
"PerlIO_fast_gets"
"PerlIO_fdopen"
"PerlIO_fileno"
"PerlIO_fill"
"PerlIO_findFILE"
"PerlIO_flush"
"PerlIO_get_base"
"PerlIO_get_bufsiz"
"PerlIO_get_cnt"
"PerlIO_get_ptr"
"PerlIO_getc"
"PerlIO_getpos"
"PerlIO_has_base"
"PerlIO_has_cntptr"
"PerlIO_importFILE"
"PerlIO_open"
"PerlIO_printf"
"PerlIO_putc"
"PerlIO_puts"
"PerlIO_read"
"PerlIO_releaseFILE"
"PerlIO_reopen"
"PerlIO_rewind"
"PerlIO_seek"
"PerlIO_set_cnt"
"PerlIO_set_ptrcnt"
"PerlIO_setlinebuf"
"PerlIO_setpos"
"PerlIO_stderr"
"PerlIO_stdin"
"PerlIO_stdout"
"PerlIO_stdoutf"
"PerlIO_tell"
"PerlIO_ungetc"
"PerlIO_unread"
"PerlIO_vprintf"
"PerlIO_write"
Described in perlapio.
int PerlIO_apply_layers(PerlIO *f, const char *mode,
const char *layers)
int PerlIO_binmode (PerlIO *f, int ptype, int imode,
const char *layers)
int PerlIO_canset_cnt (PerlIO *f)
void PerlIO_clearerr (PerlIO *f)
int PerlIO_close (PerlIO *f)
void PerlIO_debug (const char *fmt, ...)
int PerlIO_eof (PerlIO *f)
int PerlIO_error (PerlIO *f)
FILE * PerlIO_exportFILE (PerlIO *f, const char *mode)
int PerlIO_fast_gets (PerlIO *f)
PerlIO * PerlIO_fdopen (int fd, const char *mode)
int PerlIO_fileno (PerlIO *f)
int PerlIO_fill (PerlIO *f)
FILE * PerlIO_findFILE (PerlIO *f)
int PerlIO_flush (PerlIO *f)
STDCHAR * PerlIO_get_base (PerlIO *f)
SSize_t PerlIO_get_bufsiz (PerlIO *f)
SSize_t PerlIO_get_cnt (PerlIO *f)
STDCHAR * PerlIO_get_ptr (PerlIO *f)
int PerlIO_getc (PerlIO *d)
int PerlIO_getpos (PerlIO *f, SV *save)
int PerlIO_has_base (PerlIO *f)
int PerlIO_has_cntptr (PerlIO *f)
PerlIO * PerlIO_importFILE (FILE *stdio, const char *mode)
PerlIO * PerlIO_open (const char *path, const char *mode)
int PerlIO_printf (PerlIO *f, const char *fmt, ...)
int PerlIO_putc (PerlIO *f, int ch)
int PerlIO_puts (PerlIO *f, const char *string)
SSize_t PerlIO_read (PerlIO *f, void *vbuf,
Size_t count)
void PerlIO_releaseFILE (PerlIO *f, FILE *stdio)
PerlIO * PerlIO_reopen (const char *path, const char *mode,
PerlIO *old)
void PerlIO_rewind (PerlIO *f)
int PerlIO_seek (PerlIO *f, Off_t offset,
int whence)
void PerlIO_set_cnt (PerlIO *f, SSize_t cnt)
void PerlIO_set_ptrcnt (PerlIO *f, STDCHAR *ptr,
SSize_t cnt)
void PerlIO_setlinebuf (PerlIO *f)
int PerlIO_setpos (PerlIO *f, SV *saved)
PerlIO * PerlIO_stderr (PerlIO *f, const char *mode,
const char *layers)
PerlIO * PerlIO_stdin (PerlIO *f, const char *mode,
const char *layers)
PerlIO * PerlIO_stdout (PerlIO *f, const char *mode,
const char *layers)
int PerlIO_stdoutf (const char *fmt, ...)
Off_t PerlIO_tell (PerlIO *f)
int PerlIO_ungetc (PerlIO *f, int ch)
SSize_t PerlIO_unread (PerlIO *f, const void *vbuf,
Size_t count)
int PerlIO_vprintf (PerlIO *f, const char *fmt,
va_list args)
SSize_t PerlIO_write (PerlIO *f, const void *vbuf,
Size_t count)
"PERLIO_F_APPEND"
"PERLIO_F_CANREAD"
"PERLIO_F_CANWRITE"
"PERLIO_F_CRLF"
"PERLIO_F_EOF"
"PERLIO_F_ERROR"
"PERLIO_F_FASTGETS"
"PERLIO_F_LINEBUF"
"PERLIO_F_OPEN"
"PERLIO_F_RDBUF"
"PERLIO_F_TEMP"
"PERLIO_F_TRUNCATE"
"PERLIO_F_UNBUF"
"PERLIO_F_UTF8"
"PERLIO_F_WRBUF"
Described in perliol.
"PERLIO_FUNCS_CAST"
Cast the pointer "func" to be of type "PerlIO_funcs *".
"PERLIO_FUNCS_DECL"
Declare "ftab" to be a PerlIO function table, that is, of type
"PerlIO_funcs".
PERLIO_FUNCS_DECL(PerlIO * ftab)
"PERLIO_K_BUFFERED"
"PERLIO_K_CANCRLF"
"PERLIO_K_FASTGETS"
"PERLIO_K_MULTIARG"
"PERLIO_K_RAW"
Described in perliol.
"PERLIO_NOT_STDIO"
Described in perlapio.
"PL_maxsysfd"
Described in perliol.
"repeatcpy"
Make "count" copies of the "len" bytes beginning at "from", placing
them into memory beginning at "to", which must be big enough to
accommodate them all.
void repeatcpy(char *to, const char *from, SSize_t len, IV count)
"USE_STDIO"
Described in perlapio.
Integer
"CASTI32"
This symbol is defined if the C compiler can cast negative or large
floating point numbers to 32-bit ints.
"HAS_INT64_T"
This symbol will defined if the C compiler supports "int64_t".
Usually the inttypes.h needs to be included, but sometimes
sys/types.h is enough.
"HAS_LONG_LONG"
This symbol will be defined if the C compiler supports long long.
"HAS_QUAD"
This symbol, if defined, tells that there's a 64-bit integer type,
"Quad_t", and its unsigned counterpart, "Uquad_t". "QUADKIND" will
be one of "QUAD_IS_INT", "QUAD_IS_LONG", "QUAD_IS_LONG_LONG",
"QUAD_IS_INT64_T", or "QUAD_IS___INT64".
"I32df"
This symbol defines the format string used for printing a Perl I32
as a signed decimal integer.
"INT16_C"
"INT32_C"
"INT64_C"
Returns a token the C compiler recognizes for the constant "number"
of the corresponding integer type on the machine.
If the machine does not have a 64-bit type, "INT64_C" is undefined.
Use "INTMAX_C" to get the largest type available on the platform.
I16 INT16_C(number)
I32 INT32_C(number)
I64 INT64_C(number)
"INTMAX_C"
Returns a token the C compiler recognizes for the constant "number"
of the widest integer type on the machine. For example, if the
machine has "long long"s, INTMAX_C(-1) would yield
-1LL
See also, for example, "INT32_C".
Use "IV" to declare variables of the maximum usable size on this
platform.
INTMAX_C(number)
"INTSIZE"
This symbol contains the value of sizeof(int) so that the C
preprocessor can make decisions based on it.
"I8SIZE"
This symbol contains the sizeof(I8).
"I16SIZE"
This symbol contains the sizeof(I16).
"I32SIZE"
This symbol contains the sizeof(I32).
"I64SIZE"
This symbol contains the sizeof(I64).
"I8TYPE"
This symbol defines the C type used for Perl's I8.
"I16TYPE"
This symbol defines the C type used for Perl's I16.
"I32TYPE"
This symbol defines the C type used for Perl's I32.
"I64TYPE"
This symbol defines the C type used for Perl's I64.
"IV"
"I8"
"I16"
"I32"
"I64"
Described in perlguts.
"IV_MAX"
The largest signed integer that fits in an IV on this platform.
IV IV_MAX
"IV_MIN"
The negative signed integer furthest away from 0 that fits in an IV
on this platform.
IV IV_MIN
"IVSIZE"
This symbol contains the sizeof(IV).
"IVTYPE"
This symbol defines the C type used for Perl's IV.
"line_t"
The typedef to use to declare variables that are to hold line
numbers.
"LONGLONGSIZE"
This symbol contains the size of a long long, so that the C
preprocessor can make decisions based on it. It is only defined if
the system supports long long.
"LONGSIZE"
This symbol contains the value of sizeof(long) so that the C
preprocessor can make decisions based on it.
"memzero"
Set the "l" bytes starting at *d to all zeroes.
void memzero(void * d, Size_t l)
"PERL_INT_FAST8_T"
"PERL_INT_FAST16_T"
"PERL_UINT_FAST8_T"
"PERL_UINT_FAST16_T"
These are equivalent to the correspondingly-named C99 typedefs on
platforms that have those; they evaluate to "int" and "unsigned int"
on platforms that don't, so that you can portably take advantage of
this C99 feature.
"PERL_INT_MAX"
"PERL_INT_MIN"
"PERL_LONG_MAX"
"PERL_LONG_MIN"
"PERL_QUAD_MAX"
"PERL_QUAD_MIN"
"PERL_SHORT_MAX"
"PERL_SHORT_MIN"
"PERL_UCHAR_MAX"
"PERL_UCHAR_MIN"
"PERL_UINT_MAX"
"PERL_UINT_MIN"
"PERL_ULONG_MAX"
"PERL_ULONG_MIN"
"PERL_UQUAD_MAX"
"PERL_UQUAD_MIN"
"PERL_USHORT_MAX"
"PERL_USHORT_MIN"
These give the largest and smallest number representable in the
current platform in variables of the corresponding types.
For signed types, the smallest representable number is the most
negative number, the one furthest away from zero.
For C99 and later compilers, these correspond to things like
"INT_MAX", which are available to the C code. But these constants,
furnished by Perl, allow code compiled on earlier compilers to
portably have access to the same constants.
int PERL_INT_MAX
int PERL_INT_MIN
long PERL_LONG_MAX
long PERL_LONG_MIN
IV PERL_QUAD_MAX
IV PERL_QUAD_MIN
short PERL_SHORT_MAX
short PERL_SHORT_MIN
U8 PERL_UCHAR_MAX
U8 PERL_UCHAR_MIN
unsigned int PERL_UINT_MAX
unsigned int PERL_UINT_MIN
unsigned long PERL_ULONG_MAX
unsigned long PERL_ULONG_MIN
UV PERL_UQUAD_MAX
UV PERL_UQUAD_MIN
unsigned short PERL_USHORT_MAX
unsigned short PERL_USHORT_MIN
"SHORTSIZE"
This symbol contains the value of sizeof(short) so that the C
preprocessor can make decisions based on it.
"UINT16_C"
"UINT32_C"
"UINT64_C"
Returns a token the C compiler recognizes for the constant "number"
of the corresponding unsigned integer type on the machine.
If the machine does not have a 64-bit type, "UINT64_C" is undefined.
Use "UINTMAX_C" to get the largest type available on the platform.
U16 UINT16_C(number)
U32 UINT32_C(number)
U64 UINT64_C(number)
"UINTMAX_C"
Returns a token the C compiler recognizes for the constant "number"
of the widest unsigned integer type on the machine. For example, if
the machine has "long"s, UINTMAX_C(1) would yield
1UL
See also, for example, "UINT32_C".
Use "UV" to declare variables of the maximum usable size on this
platform.
UINTMAX_C(number)
"U32of"
This symbol defines the format string used for printing a Perl U32
as an unsigned octal integer.
"U8SIZE"
This symbol contains the sizeof(U8).
"U16SIZE"
This symbol contains the sizeof(U16).
"U32SIZE"
This symbol contains the sizeof(U32).
"U64SIZE"
This symbol contains the sizeof(U64).
"U8TYPE"
This symbol defines the C type used for Perl's U8.
"U16TYPE"
This symbol defines the C type used for Perl's U16.
"U32TYPE"
This symbol defines the C type used for Perl's U32.
"U64TYPE"
This symbol defines the C type used for Perl's U64.
"U32uf"
This symbol defines the format string used for printing a Perl U32
as an unsigned decimal integer.
"UV"
"U8"
"U16"
"U32"
"U64"
Described in perlguts.
"UV_MAX"
The largest unsigned integer that fits in a UV on this platform.
UV UV_MAX
"UV_MIN"
The smallest unsigned integer that fits in a UV on this platform.
It should equal zero.
UV UV_MIN
"UVSIZE"
This symbol contains the sizeof(UV).
"UVTYPE"
This symbol defines the C type used for Perl's UV.
"U32Xf"
This symbol defines the format string used for printing a Perl U32
as an unsigned hexadecimal integer in uppercase "ABCDEF".
"U32xf"
This symbol defines the format string used for printing a Perl U32
as an unsigned hexadecimal integer in lowercase abcdef.
"WIDEST_UTYPE"
Yields the widest unsigned integer type on the platform, currently
either "U32" or "U64". This can be used in declarations such as
WIDEST_UTYPE my_uv;
or casts
my_uv = (WIDEST_UTYPE) val;
I/O Formats
These are used for formatting the corresponding type For example,
instead of saying
Perl_newSVpvf(pTHX_ "Create an SV with a %d in it\n", iv);
use
Perl_newSVpvf(pTHX_ "Create an SV with a " IVdf " in it\n", iv);
This keeps you from having to know if, say an IV, needs to be printed as
%d, %ld, or something else.
"HvNAMEf"
Described in perlguts.
"HvNAMEf_QUOTEDPREFIX"
Described in perlguts.
"IVdf"
This symbol defines the format string used for printing a Perl IV as
a signed decimal integer.
"NVef"
This symbol defines the format string used for printing a Perl NV
using %e-ish floating point format.
"NVff"
This symbol defines the format string used for printing a Perl NV
using %f-ish floating point format.
"NVgf"
This symbol defines the format string used for printing a Perl NV
using %g-ish floating point format.
"PERL_PRIeldbl"
This symbol, if defined, contains the string used by stdio to format
long doubles (format 'e') for output.
"PERL_PRIfldbl"
This symbol, if defined, contains the string used by stdio to format
long doubles (format 'f') for output.
"PERL_PRIgldbl"
This symbol, if defined, contains the string used by stdio to format
long doubles (format 'g') for output.
"PERL_SCNfldbl"
This symbol, if defined, contains the string used by stdio to format
long doubles (format 'f') for input.
"PRINTF_FORMAT_NULL_OK"
Allows "__printf__" format to be null when checking printf-style
"SVf"
Described in perlguts.
"SVfARG"
Described in perlguts.
SVfARG(SV *sv)
"SVf_QUOTEDPREFIX"
Described in perlguts.
"UTF8f"
Described in perlguts.
"UTF8fARG"
Described in perlguts.
UTF8fARG(bool is_utf8, Size_t byte_len, char *str)
"UTF8f_QUOTEDPREFIX"
Described in perlguts.
"UVf"
"DEPRECATED!" It is planned to remove "UVf" from a future release
of Perl. Do not use it for new code; remove it from existing code.
Obsolete form of "UVuf", which you should convert to instead use
const char * UVf
"UVof"
This symbol defines the format string used for printing a Perl UV as
an unsigned octal integer.
"UVuf"
This symbol defines the format string used for printing a Perl UV as
an unsigned decimal integer.
"UVXf"
This symbol defines the format string used for printing a Perl UV as
an unsigned hexadecimal integer in uppercase "ABCDEF".
"UVxf"
This symbol defines the format string used for printing a Perl UV as
an unsigned hexadecimal integer in lowercase abcdef.
Lexer interface
This is the lower layer of the Perl parser, managing characters and
tokens.
"BHK"
Described in perlguts.
"lex_bufutf8"
NOTE: "lex_bufutf8" is experimental and may change or be removed
without notice.
Indicates whether the octets in the lexer buffer
("PL_parser->linestr") should be interpreted as the UTF-8 encoding
of Unicode characters. If not, they should be interpreted as
Latin-1 characters. This is analogous to the "SvUTF8" flag for
scalars.
In UTF-8 mode, it is not guaranteed that the lexer buffer actually
contains valid UTF-8. Lexing code must be robust in the face of
invalid encoding.
The actual "SvUTF8" flag of the "PL_parser->linestr" scalar is
significant, but not the whole story regarding the input character
encoding. Normally, when a file is being read, the scalar contains
octets and its "SvUTF8" flag is off, but the octets should be
interpreted as UTF-8 if the "use utf8" pragma is in effect. During
a string eval, however, the scalar may have the "SvUTF8" flag on,
and in this case its octets should be interpreted as UTF-8 unless
the "use bytes" pragma is in effect. This logic may change in the
future; use this function instead of implementing the logic
yourself.
bool lex_bufutf8()
"lex_discard_to"
NOTE: "lex_discard_to" is experimental and may change or be removed
without notice.
Discards the first part of the "PL_parser->linestr" buffer, up to
"ptr". The remaining content of the buffer will be moved, and all
pointers into the buffer updated appropriately. "ptr" must not be
later in the buffer than the position of "PL_parser->bufptr": it is
not permitted to discard text that has yet to be lexed.
Normally it is not necessarily to do this directly, because it
suffices to use the implicit discarding behaviour of
"lex_next_chunk" and things based on it. However, if a token
stretches across multiple lines, and the lexing code has kept
multiple lines of text in the buffer for that purpose, then after
completion of the token it would be wise to explicitly discard the
now-unneeded earlier lines, to avoid future multi-line tokens
growing the buffer without bound.
void lex_discard_to(char *ptr)
"lex_grow_linestr"
NOTE: "lex_grow_linestr" is experimental and may change or be
removed without notice.
Reallocates the lexer buffer ("PL_parser->linestr") to accommodate
at least "len" octets (including terminating "NUL"). Returns a
pointer to the reallocated buffer. This is necessary before making
any direct modification of the buffer that would increase its
length. "lex_stuff_pvn" provides a more convenient way to insert
text into the buffer.
Do not use "SvGROW" or "sv_grow" directly on "PL_parser->linestr";
this function updates all of the lexer's variables that point
directly into the buffer.
char * lex_grow_linestr(STRLEN len)
"lex_next_chunk"
NOTE: "lex_next_chunk" is experimental and may change or be removed
without notice.
Reads in the next chunk of text to be lexed, appending it to
"PL_parser->linestr". This should be called when lexing code has
looked to the end of the current chunk and wants to know more. It
is usual, but not necessary, for lexing to have consumed the
entirety of the current chunk at this time.
If "PL_parser->bufptr" is pointing to the very end of the current
chunk (i.e., the current chunk has been entirely consumed), normally
the current chunk will be discarded at the same time that the new
chunk is read in. If "flags" has the "LEX_KEEP_PREVIOUS" bit set,
the current chunk will not be discarded. If the current chunk has
not been entirely consumed, then it will not be discarded regardless
of the flag.
Returns true if some new text was added to the buffer, or false if
the buffer has reached the end of the input text.
bool lex_next_chunk(U32 flags)
"lex_peek_unichar"
NOTE: "lex_peek_unichar" is experimental and may change or be
removed without notice.
Looks ahead one (Unicode) character in the text currently being
lexed. Returns the codepoint (unsigned integer value) of the next
character, or -1 if lexing has reached the end of the input text.
To consume the peeked character, use "lex_read_unichar".
If the next character is in (or extends into) the next chunk of
input text, the next chunk will be read in. Normally the current
chunk will be discarded at the same time, but if "flags" has the
"LEX_KEEP_PREVIOUS" bit set, then the current chunk will not be
discarded.
If the input is being interpreted as UTF-8 and a UTF-8 encoding
error is encountered, an exception is generated.
I32 lex_peek_unichar(U32 flags)
"lex_read_space"
NOTE: "lex_read_space" is experimental and may change or be removed
without notice.
Reads optional spaces, in Perl style, in the text currently being
lexed. The spaces may include ordinary whitespace characters and
Perl-style comments. "#line" directives are processed if
encountered. "PL_parser->bufptr" is moved past the spaces, so that
it points at a non-space character (or the end of the input text).
If spaces extend into the next chunk of input text, the next chunk
will be read in. Normally the current chunk will be discarded at
the same time, but if "flags" has the "LEX_KEEP_PREVIOUS" bit set,
then the current chunk will not be discarded.
void lex_read_space(U32 flags)
"lex_read_to"
NOTE: "lex_read_to" is experimental and may change or be removed
without notice.
Consume text in the lexer buffer, from "PL_parser->bufptr" up to
"ptr". This advances "PL_parser->bufptr" to match "ptr", performing
the correct bookkeeping whenever a newline character is passed.
This is the normal way to consume lexed text.
Interpretation of the buffer's octets can be abstracted out by using
the slightly higher-level functions "lex_peek_unichar" and
"lex_read_unichar".
void lex_read_to(char *ptr)
"lex_read_unichar"
NOTE: "lex_read_unichar" is experimental and may change or be
removed without notice.
Reads the next (Unicode) character in the text currently being
lexed. Returns the codepoint (unsigned integer value) of the
character read, and moves "PL_parser->bufptr" past the character, or
returns -1 if lexing has reached the end of the input text. To non-
destructively examine the next character, use "lex_peek_unichar"
instead.
If the next character is in (or extends into) the next chunk of
input text, the next chunk will be read in. Normally the current
chunk will be discarded at the same time, but if "flags" has the
"LEX_KEEP_PREVIOUS" bit set, then the current chunk will not be
discarded.
If the input is being interpreted as UTF-8 and a UTF-8 encoding
error is encountered, an exception is generated.
I32 lex_read_unichar(U32 flags)
"lex_start"
NOTE: "lex_start" is experimental and may change or be removed
without notice.
Creates and initialises a new lexer/parser state object, supplying a
context in which to lex and parse from a new source of Perl code. A
pointer to the new state object is placed in "PL_parser". An entry
is made on the save stack so that upon unwinding, the new state
object will be destroyed and the former value of "PL_parser" will be
restored. Nothing else need be done to clean up the parsing
context.
The code to be parsed comes from "line" and "rsfp". "line", if non-
null, provides a string (in SV form) containing code to be parsed.
A copy of the string is made, so subsequent modification of "line"
does not affect parsing. "rsfp", if non-null, provides an input
stream from which code will be read to be parsed. If both are non-
null, the code in "line" comes first and must consist of complete
lines of input, and "rsfp" supplies the remainder of the source.
The "flags" parameter is reserved for future use. Currently it is
only used by perl internally, so extensions should always pass zero.
void lex_start(SV *line, PerlIO *rsfp, U32 flags)
"lex_stuff_pv"
NOTE: "lex_stuff_pv" is experimental and may change or be removed
without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"),
immediately after the current lexing point ("PL_parser->bufptr"),
reallocating the buffer if necessary. This means that lexing code
that runs later will see the characters as if they had appeared in
the input. It is not recommended to do this as part of normal
parsing, and most uses of this facility run the risk of the inserted
characters being interpreted in an unintended manner.
The string to be inserted is represented by octets starting at "pv"
and continuing to the first nul. These octets are interpreted as
either UTF-8 or Latin-1, according to whether the "LEX_STUFF_UTF8"
flag is set in "flags". The characters are recoded for the lexer
buffer, according to how the buffer is currently being interpreted
("lex_bufutf8"). If it is not convenient to nul-terminate a string
to be inserted, the "lex_stuff_pvn" function is more appropriate.
void lex_stuff_pv(const char *pv, U32 flags)
"lex_stuff_pvn"
NOTE: "lex_stuff_pvn" is experimental and may change or be removed
without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"),
immediately after the current lexing point ("PL_parser->bufptr"),
reallocating the buffer if necessary. This means that lexing code
that runs later will see the characters as if they had appeared in
the input. It is not recommended to do this as part of normal
parsing, and most uses of this facility run the risk of the inserted
characters being interpreted in an unintended manner.
The string to be inserted is represented by "len" octets starting at
"pv". These octets are interpreted as either UTF-8 or Latin-1,
according to whether the "LEX_STUFF_UTF8" flag is set in "flags".
The characters are recoded for the lexer buffer, according to how
the buffer is currently being interpreted ("lex_bufutf8"). If a
string to be inserted is available as a Perl scalar, the
"lex_stuff_sv" function is more convenient.
void lex_stuff_pvn(const char *pv, STRLEN len, U32 flags)
"lex_stuff_pvs"
NOTE: "lex_stuff_pvs" is experimental and may change or be removed
without notice.
Like "lex_stuff_pvn", but takes a literal string instead of a
string/length pair.
void lex_stuff_pvs("pv", U32 flags)
"lex_stuff_sv"
NOTE: "lex_stuff_sv" is experimental and may change or be removed
without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"),
immediately after the current lexing point ("PL_parser->bufptr"),
reallocating the buffer if necessary. This means that lexing code
that runs later will see the characters as if they had appeared in
the input. It is not recommended to do this as part of normal
parsing, and most uses of this facility run the risk of the inserted
characters being interpreted in an unintended manner.
The string to be inserted is the string value of "sv". The
characters are recoded for the lexer buffer, according to how the
buffer is currently being interpreted ("lex_bufutf8"). If a string
to be inserted is not already a Perl scalar, the "lex_stuff_pvn"
function avoids the need to construct a scalar.
void lex_stuff_sv(SV *sv, U32 flags)
"lex_unstuff"
NOTE: "lex_unstuff" is experimental and may change or be removed
without notice.
Discards text about to be lexed, from "PL_parser->bufptr" up to
"ptr". Text following "ptr" will be moved, and the buffer
shortened. This hides the discarded text from any lexing code that
runs later, as if the text had never appeared.
This is not the normal way to consume lexed text. For that, use
"lex_read_to".
void lex_unstuff(char *ptr)
"parse_arithexpr"
NOTE: "parse_arithexpr" is experimental and may change or be removed
without notice.
Parse a Perl arithmetic expression. This may contain operators of
precedence down to the bit shift operators. The expression must be
followed (and thus terminated) either by a comparison or lower-
precedence operator or by something that would normally terminate an
expression such as semicolon. If "flags" has the "PARSE_OPTIONAL"
bit set, then the expression is optional, otherwise it is mandatory.
It is up to the caller to ensure that the dynamic parser state
("PL_parser" et al) is correctly set to reflect the source of the
code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional
expression is absent, a null pointer is returned, otherwise the
pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid
op tree is returned anyway. The error is reflected in the parser
state, normally resulting in a single exception at the top level of
parsing which covers all the compilation errors that occurred. Some
compilation errors, however, will throw an exception immediately.
OP * parse_arithexpr(U32 flags)
"parse_barestmt"
NOTE: "parse_barestmt" is experimental and may change or be removed
without notice.
Parse a single unadorned Perl statement. This may be a normal
imperative statement or a declaration that has compile-time effect.
It does not include any label or other affixture. It is up to the
caller to ensure that the dynamic parser state ("PL_parser" et al)
is correctly set to reflect the source of the code to be parsed and
the lexical context for the statement.
The op tree representing the statement is returned. This may be a
null pointer if the statement is null, for example if it was
actually a subroutine definition (which has compile-time side
effects). If not null, it will be ops directly implementing the
statement, suitable to pass to "newSTATEOP". It will not normally
include a "nextstate" or equivalent op (except for those embedded in
a scope contained entirely within the statement).
If an error occurs in parsing or compilation, in most cases a valid
op tree (most likely null) is returned anyway. The error is
reflected in the parser state, normally resulting in a single
exception at the top level of parsing which covers all the
compilation errors that occurred. Some compilation errors, however,
will throw an exception immediately.
The "flags" parameter is reserved for future use, and must always be
zero.
OP * parse_barestmt(U32 flags)
"parse_block"
NOTE: "parse_block" is experimental and may change or be removed
without notice.
Parse a single complete Perl code block. This consists of an
opening brace, a sequence of statements, and a closing brace. The
block constitutes a lexical scope, so "my" variables and various
compile-time effects can be contained within it. It is up to the
caller to ensure that the dynamic parser state ("PL_parser" et al)
is correctly set to reflect the source of the code to be parsed and
the lexical context for the statement.
The op tree representing the code block is returned. This is always
a real op, never a null pointer. It will normally be a "lineseq"
list, including "nextstate" or equivalent ops. No ops to construct
any kind of runtime scope are included by virtue of it being a
block.
If an error occurs in parsing or compilation, in most cases a valid
op tree (most likely null) is returned anyway. The error is
reflected in the parser state, normally resulting in a single
exception at the top level of parsing which covers all the
compilation errors that occurred. Some compilation errors, however,
will throw an exception immediately.
The "flags" parameter is reserved for future use, and must always be
zero.
OP * parse_block(U32 flags)
"parse_fullexpr"
NOTE: "parse_fullexpr" is experimental and may change or be removed
without notice.
Parse a single complete Perl expression. This allows the full
expression grammar, including the lowest-precedence operators such
as "or". The expression must be followed (and thus terminated) by a
token that an expression would normally be terminated by: end-of-
file, closing bracketing punctuation, semicolon, or one of the
keywords that signals a postfix expression-statement modifier. If
"flags" has the "PARSE_OPTIONAL" bit set, then the expression is
optional, otherwise it is mandatory. It is up to the caller to
ensure that the dynamic parser state ("PL_parser" et al) is
correctly set to reflect the source of the code to be parsed and the
lexical context for the expression.
The op tree representing the expression is returned. If an optional
expression is absent, a null pointer is returned, otherwise the
pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid
op tree is returned anyway. The error is reflected in the parser
state, normally resulting in a single exception at the top level of
parsing which covers all the compilation errors that occurred. Some
compilation errors, however, will throw an exception immediately.
OP * parse_fullexpr(U32 flags)
"parse_fullstmt"
NOTE: "parse_fullstmt" is experimental and may change or be removed
without notice.
Parse a single complete Perl statement. This may be a normal
imperative statement or a declaration that has compile-time effect,
and may include optional labels. It is up to the caller to ensure
that the dynamic parser state ("PL_parser" et al) is correctly set
to reflect the source of the code to be parsed and the lexical
context for the statement.
The op tree representing the statement is returned. This may be a
null pointer if the statement is null, for example if it was
actually a subroutine definition (which has compile-time side
effects). If not null, it will be the result of a "newSTATEOP"
call, normally including a "nextstate" or equivalent op.
If an error occurs in parsing or compilation, in most cases a valid
op tree (most likely null) is returned anyway. The error is
reflected in the parser state, normally resulting in a single
exception at the top level of parsing which covers all the
compilation errors that occurred. Some compilation errors, however,
will throw an exception immediately.
The "flags" parameter is reserved for future use, and must always be
zero.
OP * parse_fullstmt(U32 flags)
"parse_label"
NOTE: "parse_label" is experimental and may change or be removed
without notice.
Parse a single label, possibly optional, of the type that may prefix
a Perl statement. It is up to the caller to ensure that the dynamic
parser state ("PL_parser" et al) is correctly set to reflect the
source of the code to be parsed. If "flags" has the
"PARSE_OPTIONAL" bit set, then the label is optional, otherwise it
is mandatory.
The name of the label is returned in the form of a fresh scalar. If
an optional label is absent, a null pointer is returned.
If an error occurs in parsing, which can only occur if the label is
mandatory, a valid label is returned anyway. The error is reflected
in the parser state, normally resulting in a single exception at the
top level of parsing which covers all the compilation errors that
occurred.
SV * parse_label(U32 flags)
"parse_listexpr"
NOTE: "parse_listexpr" is experimental and may change or be removed
without notice.
Parse a Perl list expression. This may contain operators of
precedence down to the comma operator. The expression must be
followed (and thus terminated) either by a low-precedence logic
operator such as "or" or by something that would normally terminate
an expression such as semicolon. If "flags" has the
"PARSE_OPTIONAL" bit set, then the expression is optional, otherwise
it is mandatory. It is up to the caller to ensure that the dynamic
parser state ("PL_parser" et al) is correctly set to reflect the
source of the code to be parsed and the lexical context for the
expression.
The op tree representing the expression is returned. If an optional
expression is absent, a null pointer is returned, otherwise the
pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid
op tree is returned anyway. The error is reflected in the parser
state, normally resulting in a single exception at the top level of
parsing which covers all the compilation errors that occurred. Some
compilation errors, however, will throw an exception immediately.
OP * parse_listexpr(U32 flags)
"parse_stmtseq"
NOTE: "parse_stmtseq" is experimental and may change or be removed
without notice.
Parse a sequence of zero or more Perl statements. These may be
normal imperative statements, including optional labels, or
declarations that have compile-time effect, or any mixture thereof.
The statement sequence ends when a closing brace or end-of-file is
encountered in a place where a new statement could have validly
started. It is up to the caller to ensure that the dynamic parser
state ("PL_parser" et al) is correctly set to reflect the source of
the code to be parsed and the lexical context for the statements.
The op tree representing the statement sequence is returned. This
may be a null pointer if the statements were all null, for example
if there were no statements or if there were only subroutine
definitions (which have compile-time side effects). If not null, it
will be a "lineseq" list, normally including "nextstate" or
equivalent ops.
If an error occurs in parsing or compilation, in most cases a valid
op tree is returned anyway. The error is reflected in the parser
state, normally resulting in a single exception at the top level of
parsing which covers all the compilation errors that occurred. Some
compilation errors, however, will throw an exception immediately.
The "flags" parameter is reserved for future use, and must always be
zero.
OP * parse_stmtseq(U32 flags)
"parse_subsignature"
NOTE: "parse_subsignature" is experimental and may change or be
removed without notice.
Parse a subroutine signature declaration. This is the contents of
the parentheses following a named or anonymous subroutine
declaration when the "signatures" feature is enabled. Note that this
function neither expects nor consumes the opening and closing
parentheses around the signature; it is the caller's job to handle
these.
This function must only be called during parsing of a subroutine;
after "start_subparse" has been called. It might allocate lexical
variables on the pad for the current subroutine.
The op tree to unpack the arguments from the stack at runtime is
returned. This op tree should appear at the beginning of the
compiled function. The caller may wish to use "op_append_list" to
build their function body after it, or splice it together with the
body before calling "newATTRSUB".
The "flags" parameter is reserved for future use, and must always be
zero.
OP * parse_subsignature(U32 flags)
"parse_termexpr"
NOTE: "parse_termexpr" is experimental and may change or be removed
without notice.
Parse a Perl term expression. This may contain operators of
precedence down to the assignment operators. The expression must be
followed (and thus terminated) either by a comma or lower-precedence
operator or by something that would normally terminate an expression
such as semicolon. If "flags" has the "PARSE_OPTIONAL" bit set,
then the expression is optional, otherwise it is mandatory. It is
up to the caller to ensure that the dynamic parser state
("PL_parser" et al) is correctly set to reflect the source of the
code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional
expression is absent, a null pointer is returned, otherwise the
pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid
op tree is returned anyway. The error is reflected in the parser
state, normally resulting in a single exception at the top level of
parsing which covers all the compilation errors that occurred. Some
compilation errors, however, will throw an exception immediately.
OP * parse_termexpr(U32 flags)
"PL_parser"
Pointer to a structure encapsulating the state of the parsing
operation currently in progress. The pointer can be locally changed
to perform a nested parse without interfering with the state of an
outer parse. Individual members of "PL_parser" have their own
documentation.
"PL_parser->bufend"
NOTE: "PL_parser->bufend" is experimental and may change or be
removed without notice.
Direct pointer to the end of the chunk of text currently being
lexed, the end of the lexer buffer. This is equal to
"SvPVX(PL_parser->linestr) + SvCUR(PL_parser->linestr)". A "NUL"
character (zero octet) is always located at the end of the buffer,
and does not count as part of the buffer's contents.
"PL_parser->bufptr"
NOTE: "PL_parser->bufptr" is experimental and may change or be
removed without notice.
Points to the current position of lexing inside the lexer buffer.
Characters around this point may be freely examined, within the
range delimited by SvPVX("PL_parser->linestr") and
"PL_parser->bufend". The octets of the buffer may be intended to be
interpreted as either UTF-8 or Latin-1, as indicated by
"lex_bufutf8".
Lexing code (whether in the Perl core or not) moves this pointer
past the characters that it consumes. It is also expected to
perform some bookkeeping whenever a newline character is consumed.
This movement can be more conveniently performed by the function
"lex_read_to", which handles newlines appropriately.
Interpretation of the buffer's octets can be abstracted out by using
the slightly higher-level functions "lex_peek_unichar" and
"lex_read_unichar".
"PL_parser->linestart"
NOTE: "PL_parser->linestart" is experimental and may change or be
removed without notice.
Points to the start of the current line inside the lexer buffer.
This is useful for indicating at which column an error occurred, and
not much else. This must be updated by any lexing code that
consumes a newline; the function "lex_read_to" handles this detail.
"PL_parser->linestr"
NOTE: "PL_parser->linestr" is experimental and may change or be
removed without notice.
Buffer scalar containing the chunk currently under consideration of
the text currently being lexed. This is always a plain string
scalar (for which "SvPOK" is true). It is not intended to be used
as a scalar by normal scalar means; instead refer to the buffer
directly by the pointer variables described below.
The lexer maintains various "char*" pointers to things in the
"PL_parser->linestr" buffer. If "PL_parser->linestr" is ever
reallocated, all of these pointers must be updated. Don't attempt
to do this manually, but rather use "lex_grow_linestr" if you need
to reallocate the buffer.
The content of the text chunk in the buffer is commonly exactly one
complete line of input, up to and including a newline terminator,
but there are situations where it is otherwise. The octets of the
buffer may be intended to be interpreted as either UTF-8 or Latin-1.
The function "lex_bufutf8" tells you which. Do not use the "SvUTF8"
flag on this scalar, which may disagree with it.
For direct examination of the buffer, the variable
"PL_parser->bufend" points to the end of the buffer. The current
lexing position is pointed to by "PL_parser->bufptr". Direct use of
these pointers is usually preferable to examination of the scalar
through normal scalar means.
"suspend_compcv"
Implements part of the concept of a "suspended compilation CV",
which can be used to pause the parser and compiler during parsing a
CV in order to come back to it later on.
This function saves the current state of the subroutine under
compilation ("PL_compcv") into the supplied buffer. This should be
used initially to create the state in the buffer, as the final thing
before a "LEAVE" within a block.
ENTER;
start_subparse(0);
...
suspend_compcv(&buffer);
LEAVE;
Once suspended, the "resume_compcv_final" or
"resume_compcv_and_save" function can later be used to continue the
parsing from the point this stopped.
void suspend_compcv(struct suspended_compcv *buffer)
"wrap_infix_plugin"
NOTE: "wrap_infix_plugin" is experimental and may change or be
removed without notice.
NOTE: This API exists entirely for the purpose of making the CPAN
module "XS::Parse::Infix" work. It is not expected that additional
modules will make use of it; rather, that they should use
"XS::Parse::Infix" to provide parsing of new infix operators.
Puts a C function into the chain of infix plugins. This is the
preferred way to manipulate the "PL_infix_plugin" variable.
"new_plugin" is a pointer to the C function that is to be added to
the infix plugin chain, and "old_plugin_p" points to a storage
location where a pointer to the next function in the chain will be
stored. The value of "new_plugin" is written into the
"PL_infix_plugin" variable, while the value previously stored there
is written to *old_plugin_p.
Direct access to "PL_infix_plugin" should be avoided.
void wrap_infix_plugin(Perl_infix_plugin_t new_plugin,
Perl_infix_plugin_t *old_plugin_p)
"wrap_keyword_plugin"
NOTE: "wrap_keyword_plugin" is experimental and may change or be
removed without notice.
Puts a C function into the chain of keyword plugins. This is the
preferred way to manipulate the "PL_keyword_plugin" variable.
"new_plugin" is a pointer to the C function that is to be added to
the keyword plugin chain, and "old_plugin_p" points to the storage
location where a pointer to the next function in the chain will be
stored. The value of "new_plugin" is written into the
"PL_keyword_plugin" variable, while the value previously stored
there is written to *old_plugin_p.
"PL_keyword_plugin" is global to an entire process, and a module
wishing to hook keyword parsing may find itself invoked more than
once per process, typically in different threads. To handle that
situation, this function is idempotent. The location *old_plugin_p
must initially (once per process) contain a null pointer. A C
variable of static duration (declared at file scope, typically also
marked "static" to give it internal linkage) will be implicitly
initialised appropriately, if it does not have an explicit
initialiser. This function will only actually modify the plugin
chain if it finds *old_plugin_p to be null. This function is also
thread safe on the small scale. It uses appropriate locking to
avoid race conditions in accessing "PL_keyword_plugin".
When this function is called, the function referenced by
"new_plugin" must be ready to be called, except for *old_plugin_p
being unfilled. In a threading situation, "new_plugin" may be
called immediately, even before this function has returned.
*old_plugin_p will always be appropriately set before "new_plugin"
is called. If "new_plugin" decides not to do anything special with
the identifier that it is given (which is the usual case for most
calls to a keyword plugin), it must chain the plugin function
referenced by *old_plugin_p.
Taken all together, XS code to install a keyword plugin should
typically look something like this:
static Perl_keyword_plugin_t next_keyword_plugin;
static OP *my_keyword_plugin(pTHX_
char *keyword_ptr, STRLEN keyword_len, OP **op_ptr)
{
if (memEQs(keyword_ptr, keyword_len,
"my_new_keyword")) {
...
} else {
return next_keyword_plugin(aTHX_
keyword_ptr, keyword_len, op_ptr);
}
}
BOOT:
wrap_keyword_plugin(my_keyword_plugin,
&next_keyword_plugin);
Direct access to "PL_keyword_plugin" should be avoided.
void wrap_keyword_plugin(Perl_keyword_plugin_t new_plugin,
Perl_keyword_plugin_t *old_plugin_p)
Locales
"DECLARATION_FOR_LC_NUMERIC_MANIPULATION"
This macro should be used as a statement. It declares a private
variable (whose name begins with an underscore) that is needed by
the other macros in this section. Failing to include this correctly
should lead to a syntax error. For compatibility with C89 C
compilers it should be placed in a block before any executable
statements.
void DECLARATION_FOR_LC_NUMERIC_MANIPULATION
"foldEQ_locale"
Returns true if the leading "len" bytes of the strings "s1" and "s2"
are the same case-insensitively in the current locale; false
otherwise.
I32 foldEQ_locale(const char *a, const char *b, I32 len)
"HAS_DUPLOCALE"
This symbol, if defined, indicates that the "duplocale" routine is
available to duplicate a locale object.
"HAS_FREELOCALE"
This symbol, if defined, indicates that the "freelocale" routine is
available to deallocates the resources associated with a locale
object.
"HAS_LC_MONETARY_2008"
This symbol, if defined, indicates that the localeconv routine is
available and has the additional members added in "POSIX"
1003.1-2008.
"HAS_LOCALECONV"
This symbol, if defined, indicates that the "localeconv" routine is
available for numeric and monetary formatting conventions.
"HAS_LOCALECONV_L"
This symbol, if defined, indicates that the "localeconv_l" routine
is available to query certain information about a locale.
"HAS_NEWLOCALE"
This symbol, if defined, indicates that the "newlocale" routine is
available to return a new locale object or modify an existing locale
object.
"HAS_NL_LANGINFO"
This symbol, if defined, indicates that the "nl_langinfo" routine is
available to return locale data. You will also need langinfo.h and
therefore "I_LANGINFO".
"HAS_NL_LANGINFO_L"
This symbol, if defined, indicates that the "nl_langinfo_l" routine
is available to return locale data. You will also need langinfo.h
and therefore "I_LANGINFO".
"HAS_QUERYLOCALE"
This symbol, if defined, indicates that the "querylocale" routine is
available to return the name of the locale for a category mask.
"HAS_SETLOCALE"
This symbol, if defined, indicates that the "setlocale" routine is
available to handle locale-specific ctype implementations.
"HAS_SETLOCALE_R"
This symbol, if defined, indicates that the "setlocale_r" routine is
available to setlocale re-entrantly.
"HAS_USELOCALE"
This symbol, if defined, indicates that the "uselocale" routine is
available to set the current locale for the calling thread.
"I_LANGINFO"
This symbol, if defined, indicates that langinfo.h exists and should
be included.
#ifdef I_LANGINFO
#include <langinfo.h>
#endif
"I_LOCALE"
This symbol, if defined, indicates to the C program that it should
include locale.h.
#ifdef I_LOCALE
#include <locale.h>
#endif
"IN_LOCALE"
Evaluates to TRUE if the plain locale pragma without a parameter
("use locale") is in effect.
bool IN_LOCALE
"IN_LOCALE_COMPILETIME"
Evaluates to TRUE if, when compiling a perl program (including an
"eval") if the plain locale pragma without a parameter
("use locale") is in effect.
bool IN_LOCALE_COMPILETIME
"IN_LOCALE_RUNTIME"
Evaluates to TRUE if, when executing a perl program (including an
"eval") if the plain locale pragma without a parameter
("use locale") is in effect.
bool IN_LOCALE_RUNTIME
"I_XLOCALE"
This symbol, if defined, indicates to the C program that the header
xlocale.h is available. See also "NEED_XLOCALE_H"
#ifdef I_XLOCALE
#include <xlocale.h>
#endif
"NEED_XLOCALE_H"
This symbol, if defined, indicates that the C program should include
xlocale.h to get newlocale() and its friends.
"Perl_langinfo"
"Perl_langinfo8"
"Perl_langinfo" is an (almost) drop-in replacement for the system
nl_langinfo(3), taking the same "item" parameter values, and
returning the same information. But it is more thread-safe than
regular nl_langinfo(), and hides the quirks of Perl's locale
handling from your code, and can be used on systems that lack a
native "nl_langinfo".
However, you should instead use either the improved version of this,
"Perl_langinfo8", or even better, "sv_langinfo". The latter returns
an SV, handling all the possible non-standard returns of
nl_langinfo(), including the UTF8ness of any returned string.
"Perl_langinfo8" is identical to "Perl_langinfo" except for an
additional parameter, a pointer to a variable declared as
""utf8ness_t"", into which it returns to you how you should treat
the returned string with regards to it being encoded in UTF-8 or
not.
These two functions share private per-thread memory that will be
changed the next time either one of them is called with any input,
but not before.
Concerning the differences between these and plain nl_langinfo():
a. "Perl_langinfo8" has an extra parameter, described above.
Besides this, the other reason they aren't quite a drop-in
replacement is actually an advantage. The "const"ness of the
return allows the compiler to catch attempts to write into the
returned buffer, which is illegal and could cause run-time
crashes.
b. They deliver the correct results for the "RADIXCHAR" and
"THOUSEP" items, without you having to write extra code. The
reason for the extra code would be because these are from the
"LC_NUMERIC" locale category, which is normally kept set by Perl
so that the radix is a dot, and the separator is the empty
string, no matter what the underlying locale is supposed to be,
and so to get the expected results, you have to temporarily
toggle into the underlying locale, and later toggle back. (You
could use plain "nl_langinfo" and
"STORE_LC_NUMERIC_FORCE_TO_UNDERLYING" for this but then you
wouldn't get the other advantages of Perl_langinfo(); not
keeping "LC_NUMERIC" in the C (or equivalent) locale would break
a lot of CPAN, which is expecting the radix (decimal point)
character to be a dot.)
c. The system function they replace can have its static return
buffer trashed, not only by a subsequent call to that function,
but by a "freelocale", "setlocale", or other locale change. The
returned buffer of these functions is not changed until the next
call to one or the other, so the buffer is never in a trashed
state.
d. The return buffer is per-thread, so it also is never overwritten
by a call to these functions from another thread; unlike the
function it replaces.
e. But most importantly, they work on systems that don't have
"nl_langinfo", such as Windows, hence making your code more
portable. Of the fifty-some possible items specified by the
POSIX 2008 standard,
<https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/langinfo.h.html>,
only one is completely unimplemented, though on non-Windows
platforms, another significant one is not fully implemented).
They use various techniques to recover the other items,
including calling localeconv(3), and strftime(3), both of which
are specified in C89, so should be always be available. Later
strftime() versions have additional capabilities. If an item is
not available on your system, this returns either the value
associated with the C locale, or simply "", whichever is more
appropriate.
It is important to note that, when called with an item that is
recovered by using "localeconv", the buffer from any previous
explicit call to localeconv(3) will be overwritten. But you
shouldn't be using "localeconv" anyway because it is is very
much not thread-safe, and suffers from the same problems
outlined in item 'b.' above for the fields it returns that are
controlled by the LC_NUMERIC locale category. Instead, avoid
all of those problems by calling "Perl_localeconv", which is
thread-safe; or by using the methods given in perlcall to call
POSIX::localeconv(), which is also thread-safe.
The details for those items which may deviate from what this
emulation returns and what a native nl_langinfo() would return are
specified in I18N::Langinfo.
const char * Perl_langinfo (const nl_item item)
const char * Perl_langinfo8(const nl_item item,
utf8ness_t *utf8ness)
"PERL_LC_ALL_CATEGORY_POSITIONS_INIT"
This symbol, when defined, gives the C initializer for an array
whose element [0] is the first category in the string returned by
"setlocale(LC_ALL, NULL)" when not all categories are the same, on
systems that use a positional notation. After element [0] is
"LC_ALL_SEPARATOR", then the category given by element [1] and so
on.
"PERL_LC_ALL_SEPARATOR"
This symbol, if defined, gives the string returned by
"setlocale(LC_ALL, NULL)" to separate categories that are in
different locales on systems that use a positional notation as
opposed to 'name=value' pairs. An example on some platforms could
be the '/' in "C/"de_DE"/C/"en_UK"/C/C"
"PERL_LC_ALL_USES_NAME_VALUE_PAIRS"
This symbol, if defined, indicates to the C program that the string
returned by "setlocale(LC_ALL, NULL)" uses 'name=value;' pairs to
indicate what each category's locale is when they aren't all set to
the same locale. For example,
""LC_NUMERIC"=C;"LC_CTYPE"="de_DE";..." When not defined, the
system uses positional notation.
"Perl_localeconv"
This is a thread-safe version of the libc localeconv(3). It is the
same as POSIX::localeconv (returning a hash of the localeconv()
fields), but directly callable from XS code. The hash is
mortalized, so must be dealt with immediately.
HV * Perl_localeconv(pTHX)
"Perl_setlocale"
This is an (almost) drop-in replacement for the system setlocale(3),
taking the same parameters, and returning the same information,
except that it returns the correct underlying "LC_NUMERIC" locale.
Regular "setlocale" will instead return "C" if the underlying locale
has a non-dot decimal point character, or a non-empty thousands
separator for displaying floating point numbers. This is because
perl keeps that locale category such that it has a dot and empty
separator, changing the locale briefly during the operations where
the underlying one is required. "Perl_setlocale" knows about this,
and compensates; regular "setlocale" doesn't.
Another reason it isn't completely a drop-in replacement is that it
is declared to return "const char *", whereas the system setlocale
omits the "const" (presumably because its API was specified long
ago, and can't be updated; it is illegal to change the information
"setlocale" returns; doing so leads to segfaults.)
Finally, "Perl_setlocale" works under all circumstances, whereas
plain "setlocale" can be completely ineffective on some platforms
under some configurations.
Changing the locale is not a good idea when more than one thread is
running, except on systems where the predefined variable
"${^SAFE_LOCALES}" is non-zero. This is because on such systems the
locale is global to the whole process and not local to just the
thread calling the function. So changing it in one thread
instantaneously changes it in all. On some such systems, the system
setlocale() is ineffective, returning the wrong information, and
failing to actually change the locale. z/OS refuses to try to
change the locale once a second thread is created.
"Perl_setlocale", should give you accurate results of what actually
happened on these problematic platforms, returning NULL if the
system forbade the locale change.
The return points to a per-thread static buffer, which is
overwritten the next time "Perl_setlocale" is called from the same
thread.
const char * Perl_setlocale(const int category,
const char *locale)
"RESTORE_LC_NUMERIC"
This is used in conjunction with one of the macros
"STORE_LC_NUMERIC_SET_TO_NEEDED" and
"STORE_LC_NUMERIC_FORCE_TO_UNDERLYING" to properly restore the
"LC_NUMERIC" state.
A call to "DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been
made to declare at compile time a private variable used by this
macro and the two "STORE" ones. This macro should be called as a
single statement, not an expression, but with an empty argument
list, like this:
{
DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
...
RESTORE_LC_NUMERIC();
...
}
void RESTORE_LC_NUMERIC()
"SETLOCALE_ACCEPTS_ANY_LOCALE_NAME"
This symbol, if defined, indicates that the setlocale routine is
available and it accepts any input locale name as valid.
"STORE_LC_NUMERIC_FORCE_TO_UNDERLYING"
This is used by XS code that is "LC_NUMERIC" locale-aware to force
the locale for category "LC_NUMERIC" to be what perl thinks is the
current underlying locale. (The perl interpreter could be wrong
about what the underlying locale actually is if some C or XS code
has called the C library function setlocale(3) behind its back;
calling "sync_locale" before calling this macro will update perl's
records.)
A call to "DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been
made to declare at compile time a private variable used by this
macro. This macro should be called as a single statement, not an
expression, but with an empty argument list, like this:
{
DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
...
STORE_LC_NUMERIC_FORCE_TO_UNDERLYING();
...
RESTORE_LC_NUMERIC();
...
}
The private variable is used to save the current locale state, so
that the requisite matching call to "RESTORE_LC_NUMERIC" can restore
it.
On threaded perls not operating with thread-safe functionality, this
macro uses a mutex to force a critical section. Therefore the
matching RESTORE should be close by, and guaranteed to be called.
void STORE_LC_NUMERIC_FORCE_TO_UNDERLYING()
"STORE_LC_NUMERIC_SET_TO_NEEDED"
This is used to help wrap XS or C code that is "LC_NUMERIC" locale-
aware. This locale category is generally kept set to a locale where
the decimal radix character is a dot, and the separator between
groups of digits is empty. This is because most XS code that reads
floating point numbers is expecting them to have this syntax.
This macro makes sure the current "LC_NUMERIC" state is set
properly, to be aware of locale if the call to the XS or C code from
the Perl program is from within the scope of a "use locale"; or to
ignore locale if the call is instead from outside such scope.
This macro is the start of wrapping the C or XS code; the wrap
ending is done by calling the "RESTORE_LC_NUMERIC" macro after the
operation. Otherwise the state can be changed that will adversely
affect other XS code.
A call to "DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been
made to declare at compile time a private variable used by this
macro. This macro should be called as a single statement, not an
expression, but with an empty argument list, like this:
{
DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
...
STORE_LC_NUMERIC_SET_TO_NEEDED();
...
RESTORE_LC_NUMERIC();
...
}
On threaded perls not operating with thread-safe functionality, this
macro uses a mutex to force a critical section. Therefore the
matching RESTORE should be close by, and guaranteed to be called;
see "WITH_LC_NUMERIC_SET_TO_NEEDED" for a more contained way to
ensure that.
void STORE_LC_NUMERIC_SET_TO_NEEDED()
"STORE_LC_NUMERIC_SET_TO_NEEDED_IN"
Same as "STORE_LC_NUMERIC_SET_TO_NEEDED" with in_lc_numeric provided
as the precalculated value of IN_LC(LC_NUMERIC). It is the caller's
responsibility to ensure that the status of "PL_compiling" and
"PL_hints" cannot have changed since the precalculation.
void STORE_LC_NUMERIC_SET_TO_NEEDED_IN(bool in_lc_numeric)
"sv_langinfo"
This is the preferred interface for accessing the data that
nl_langinfo(3) provides (or Perl's emulation of it on platforms
lacking it), returning an SV. Unlike, the earlier-defined
interfaces to this ("Perl_langinfo" and "Perl_langinfo8"), which
return strings, the UTF8ness of the result is automatically handled
for you. And like them, it is thread-safe and automatically handles
getting the proper values for the "RADIXCHAR" and "THOUSEP" items
(that calling the plain libc nl_langinfo() could give the wrong
results for). Like them, this also doesn't play well with the libc
localeconv(); use POSIX::localeconv() instead.
There are a few deviations from what a native nl_langinfo() would
return and what this returns on platforms that don't implement that
function. These are detailed in I18N::Langinfo.
SV * sv_langinfo(const nl_item item)
"switch_to_global_locale"
This function copies the locale state of the calling thread into the
program's global locale, and converts the thread to use that global
locale.
It is intended so that Perl can safely be used with C libraries that
access the global locale and which can't be converted to not access
it. Effectively, this means libraries that call setlocale(3) on
non-Windows systems. (For portability, it is a good idea to use it
on Windows as well.)
A downside of using it is that it disables the services that Perl
provides to hide locale gotchas from your code. The service you
most likely will miss regards the radix character (decimal point) in
floating point numbers. Code executed after this function is called
can no longer just assume that this character is correct for the
current circumstances.
To return to Perl control, and restart the gotcha prevention
services, call "sync_locale". Behavior is undefined for any pure
Perl code that executes while the switch is in effect.
The global locale and the per-thread locales are independent. As
long as just one thread converts to the global locale, everything
works smoothly. But if more than one does, they can easily
interfere with each other, and races are likely. On Windows systems
prior to Visual Studio 15 (at which point Microsoft fixed a bug),
races can occur (even if only one thread has been converted to the
global locale), but only if you use the following operations:
POSIX::localeconv
I18N::Langinfo, items "CRNCYSTR" and "THOUSEP"
"sv_langinfo" in perlapi, items "CRNCYSTR" and "THOUSEP"
The first item is not fixable (except by upgrading to a later Visual
Studio release), but it would be possible to work around the latter
two items by having Perl change its algorithm for calculating these
to use Windows API functions (likely "GetNumberFormat" and
"GetCurrencyFormat"); patches welcome.
XS code should never call plain "setlocale", but should instead be
converted to either call "Perl_setlocale" (which is a drop-in for
the system "setlocale") or use the methods given in perlcall to call
"POSIX::setlocale". Either one will transparently properly handle
all cases of single- vs multi-thread, POSIX 2008-supported or not.
void switch_to_global_locale()
"sync_locale"
This function copies the state of the program global locale into the
calling thread, and converts that thread to using per-thread
locales, if it wasn't already, and the platform supports them. The
LC_NUMERIC locale is toggled into the standard state (using the C
locale's conventions), if not within the lexical scope of
"use locale".
Perl will now consider itself to have control of the locale.
Since unthreaded perls have only a global locale, this function is a
no-op without threads.
This function is intended for use with C libraries that do locale
manipulation. It allows Perl to accommodate the use of them. Call
this function before transferring back to Perl space so that it
knows what state the C code has left things in.
XS code should not manipulate the locale on its own. Instead,
"Perl_setlocale" can be used at any time to query or change the
locale (though changing the locale is antisocial and dangerous on
multi-threaded systems that don't have multi-thread safe locale
operations. (See "Multi-threaded operation" in perllocale).
Using the libc setlocale(3) function should be avoided.
Nevertheless, certain non-Perl libraries called from XS, do call it,
and their behavior may not be able to be changed. This function,
along with "switch_to_global_locale", can be used to get seamless
behavior in these circumstances, as long as only one thread is
involved.
If the library has an option to turn off its locale manipulation,
doing that is preferable to using this mechanism. "Gtk" is such a
library.
The return value is a boolean: TRUE if the global locale at the time
of call was in effect for the caller; and FALSE if a per-thread
locale was in effect.
bool sync_locale()
"WITH_LC_NUMERIC_SET_TO_NEEDED"
This macro invokes the supplied statement or block within the
context of a "STORE_LC_NUMERIC_SET_TO_NEEDED" ..
"RESTORE_LC_NUMERIC" pair if required, so eg:
WITH_LC_NUMERIC_SET_TO_NEEDED(
SNPRINTF_G(fv, ebuf, sizeof(ebuf), precis)
);
is equivalent to:
{
#ifdef USE_LOCALE_NUMERIC
DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
STORE_LC_NUMERIC_SET_TO_NEEDED();
#endif
SNPRINTF_G(fv, ebuf, sizeof(ebuf), precis);
#ifdef USE_LOCALE_NUMERIC
RESTORE_LC_NUMERIC();
#endif
}
void WITH_LC_NUMERIC_SET_TO_NEEDED(block)
"WITH_LC_NUMERIC_SET_TO_NEEDED_IN"
Same as "WITH_LC_NUMERIC_SET_TO_NEEDED" with in_lc_numeric provided
as the precalculated value of IN_LC(LC_NUMERIC). It is the caller's
responsibility to ensure that the status of "PL_compiling" and
"PL_hints" cannot have changed since the precalculation.
void WITH_LC_NUMERIC_SET_TO_NEEDED_IN(bool in_lc_numeric, block)
Magic
"Magic" is special data attached to SV structures in order to give them
"magical" properties. When any Perl code tries to read from, or assign
to, an SV marked as magical, it calls the 'get' or 'set' function
associated with that SV's magic. A get is called prior to reading an
SV, in order to give it a chance to update its internal value (get on $.
writes the line number of the last read filehandle into the SV's IV
slot), while set is called after an SV has been written to, in order to
allow it to make use of its changed value (set on $/ copies the SV's new
value to the PL_rs global variable).
Magic is implemented as a linked list of MAGIC structures attached to
the SV. Each MAGIC struct holds the type of the magic, a pointer to an
array of functions that implement the get(), set(), length() etc
functions, plus space for some flags and pointers. For example, a tied
variable has a MAGIC structure that contains a pointer to the object
associated with the tie.
"mg_clear"
Clear something magical that the SV represents. See "sv_magic".
int mg_clear(SV *sv)
"mg_copy"
Copies the magic from one SV to another. See "sv_magic".
int mg_copy(SV *sv, SV *nsv, const char *key, I32 klen)
"MGf_COPY"
"MGf_DUP"
"MGf_LOCAL"
Described in perlguts.
"mg_find"
Finds the magic pointer for "type" matching the SV. See "sv_magic".
MAGIC * mg_find(const SV *sv, int type)
"mg_findext"
Finds the magic pointer of "type" with the given "vtbl" for the
"SV". See "sv_magicext".
MAGIC * mg_findext(const SV *sv, int type, const MGVTBL *vtbl)
"mg_free"
Free any magic storage used by the SV. See "sv_magic".
int mg_free(SV *sv)
"mg_freeext"
Remove any magic of type "how" using virtual table "vtbl" from the
SV "sv". See "sv_magic".
"mg_freeext(sv, how, NULL)" is equivalent to "mg_free_type(sv,
how)".
void mg_freeext(SV *sv, int how, const MGVTBL *vtbl)
"mg_free_type"
Remove any magic of type "how" from the SV "sv". See "sv_magic".
void mg_free_type(SV *sv, int how)
"mg_get"
Do magic before a value is retrieved from the SV. The type of SV
must be >= "SVt_PVMG". See "sv_magic".
int mg_get(SV *sv)
"mg_magical"
Turns on the magical status of an SV. See "sv_magic".
void mg_magical(SV *sv)
"mg_set"
Do magic after a value is assigned to the SV. See "sv_magic".
int mg_set(SV *sv)
"MGVTBL"
Described in perlguts.
"PERL_MAGIC_arylen"
"PERL_MAGIC_arylen_p"
"PERL_MAGIC_backref"
"PERL_MAGIC_bm"
"PERL_MAGIC_checkcall"
"PERL_MAGIC_collxfrm"
"PERL_MAGIC_dbfile"
"PERL_MAGIC_dbline"
"PERL_MAGIC_debugvar"
"PERL_MAGIC_defelem"
"PERL_MAGIC_destruct"
"PERL_MAGIC_env"
"PERL_MAGIC_envelem"
"PERL_MAGIC_ext"
"PERL_MAGIC_extvalue"
"PERL_MAGIC_fm"
"PERL_MAGIC_hints"
"PERL_MAGIC_hintselem"
"PERL_MAGIC_hook"
"PERL_MAGIC_hookelem"
"PERL_MAGIC_isa"
"PERL_MAGIC_isaelem"
"PERL_MAGIC_lvref"
"PERL_MAGIC_nkeys"
"PERL_MAGIC_nonelem"
"PERL_MAGIC_overload_table"
"PERL_MAGIC_pos"
"PERL_MAGIC_qr"
"PERL_MAGIC_regdata"
"PERL_MAGIC_regdatum"
"PERL_MAGIC_regex_global"
"PERL_MAGIC_rhash"
"PERL_MAGIC_shared"
"PERL_MAGIC_shared_scalar"
"PERL_MAGIC_sig"
"PERL_MAGIC_sigelem"
"PERL_MAGIC_substr"
"PERL_MAGIC_sv"
"PERL_MAGIC_symtab"
"PERL_MAGIC_taint"
"PERL_MAGIC_tied"
"PERL_MAGIC_tiedelem"
"PERL_MAGIC_tiedscalar"
"PERL_MAGIC_utf8"
"PERL_MAGIC_uvar"
"PERL_MAGIC_uvar_elem"
"PERL_MAGIC_vec"
"PERL_MAGIC_vstring"
Described in perlguts.
"SvTIED_obj"
Described in perlinterp.
SvTIED_obj(SV *sv, MAGIC *mg)
Memory Management
"dump_mstats"
When enabled by compiling with "-DDEBUGGING_MSTATS", print out
statistics about malloc as two lines of numbers, one showing the
length of the free list for each size category, the second showing
the number of mallocs - frees for each size category.
"s", if not NULL, is used as a phrase to include in the output, such
as "after compilation".
void dump_mstats(const char *s)
"HASATTRIBUTE_MALLOC"
Can we handle "GCC" attribute for malloc-style functions.
"HAS_MALLOC_GOOD_SIZE"
This symbol, if defined, indicates that the "malloc_good_size"
routine is available for use.
"HAS_MALLOC_SIZE"
This symbol, if defined, indicates that the "malloc_size" routine is
available for use.
"I_MALLOCMALLOC"
This symbol, if defined, indicates to the C program that it should
include malloc/malloc.h.
#ifdef I_MALLOCMALLOC
#include <mallocmalloc.h>
#endif
"MYMALLOC"
This symbol, if defined, indicates that we're using our own malloc.
"Newx"
"safemalloc"
The XSUB-writer's interface to the C "malloc" function.
Memory obtained by this should ONLY be freed with "Safefree".
In 5.9.3, Newx() and friends replace the older New() API, and drops
the first parameter, x, a debug aid which allowed callers to
identify themselves. This aid has been superseded by a new build
option, PERL_MEM_LOG (see "PERL_MEM_LOG" in perlhacktips). The
older API is still there for use in XS modules supporting older
perls.
void Newx (void* ptr, int nitems, type)
void* safemalloc(size_t size)
"Newxc"
The XSUB-writer's interface to the C "malloc" function, with cast.
See also "Newx".
Memory obtained by this should ONLY be freed with "Safefree".
void Newxc(void* ptr, int nitems, type, cast)
"Newxz"
"safecalloc"
The XSUB-writer's interface to the C "calloc" function. The
allocated memory is zeroed with "memzero". See also "Newx".
Memory obtained by this should ONLY be freed with "Safefree".
void Newxz (void* ptr, int nitems, type)
void* safecalloc(size_t nitems, size_t item_size)
"PERL_MALLOC_WRAP"
This symbol, if defined, indicates that we'd like malloc wrap
checks.
"Renew"
"saferealloc"
The XSUB-writer's interface to the C "realloc" function.
Memory obtained by this should ONLY be freed with "Safefree".
void Renew (void* ptr, int nitems, type)
void* saferealloc(void *ptr, size_t size)
"Renewc"
The XSUB-writer's interface to the C "realloc" function, with cast.
Memory obtained by this should ONLY be freed with "Safefree".
void Renewc(void* ptr, int nitems, type, cast)
"Safefree"
The XSUB-writer's interface to the C "free" function.
This should ONLY be used on memory obtained using "Newx" and
friends.
void Safefree(void* ptr)
"safesyscalloc"
Safe version of system's calloc()
Malloc_t safesyscalloc(MEM_SIZE elements, MEM_SIZE size)
"safesysfree"
Safe version of system's free()
Free_t safesysfree(Malloc_t where)
"safesysmalloc"
Paranoid version of system's malloc()
Malloc_t safesysmalloc(MEM_SIZE nbytes)
"safesysrealloc"
Paranoid version of system's realloc()
Malloc_t safesysrealloc(Malloc_t where, MEM_SIZE nbytes)
MRO
These functions are related to the method resolution order of perl
classes Also see perlmroapi.
"HvMROMETA"
Described in perlmroapi.
struct mro_meta * HvMROMETA(HV *hv)
"mro_get_from_name"
Returns the previously registered mro with the given "name", or NULL
if not registered. See ""mro_register"".
NOTE: "mro_get_from_name" must be explicitly called as
"Perl_mro_get_from_name" with an "aTHX_" parameter.
const struct mro_alg * Perl_mro_get_from_name(pTHX_ SV *name)
"mro_get_linear_isa"
Returns the mro linearisation for the given stash. By default, this
will be whatever "mro_get_linear_isa_dfs" returns unless some other
MRO is in effect for the stash. The return value is a read-only AV*
whose values are string SVs giving class names.
You are responsible for SvREFCNT_inc() on the return value if you
plan to store it anywhere semi-permanently (otherwise it might be
deleted out from under you the next time the cache is invalidated).
AV * mro_get_linear_isa(HV *stash)
"MRO_GET_PRIVATE_DATA"
Described in perlmroapi.
SV* MRO_GET_PRIVATE_DATA(struct mro_meta *const smeta,
const struct mro_alg *const which)
"mro_method_changed_in"
Invalidates method caching on any child classes of the given stash,
so that they might notice the changes in this one.
Ideally, all instances of "PL_sub_generation++" in perl source
outside of mro.c should be replaced by calls to this.
Perl automatically handles most of the common ways a method might be
redefined. However, there are a few ways you could change a method
in a stash without the cache code noticing, in which case you need
to call this method afterwards:
1) Directly manipulating the stash HV entries from XS code.
2) Assigning a reference to a readonly scalar constant into a stash
entry in order to create a constant subroutine (like constant.pm
does).
This same method is available from pure perl via,
mro::method_changed_in(classname).
void mro_method_changed_in(HV *stash)
"mro_register"
Registers a custom mro plugin. See perlmroapi for details on this
and other mro functions.
NOTE: "mro_register" must be explicitly called as
"Perl_mro_register" with an "aTHX_" parameter.
void Perl_mro_register(pTHX_ const struct mro_alg *mro)
"mro_set_mro"
Set "meta" to the value contained in the registered mro plugin whose
name is "name".
Croaks if "name" hasn't been registered
NOTE: "mro_set_mro" must be explicitly called as "Perl_mro_set_mro"
with an "aTHX_" parameter.
void Perl_mro_set_mro(pTHX_ struct mro_meta * const meta,
SV * const name)
"mro_set_private_data"
Described in perlmroapi.
NOTE: "mro_set_private_data" must be explicitly called as
"Perl_mro_set_private_data" with an "aTHX_" parameter.
SV * Perl_mro_set_private_data(pTHX_
struct mro_meta * const smeta,
const struct mro_alg * const which,
SV * const data)
Multicall Functions
"dMULTICALL"
Declare local variables for a multicall. See "LIGHTWEIGHT
CALLBACKS" in perlcall.
dMULTICALL;
"MULTICALL"
Make a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in
perlcall.
MULTICALL;
"POP_MULTICALL"
Closing bracket for a lightweight callback. See "LIGHTWEIGHT
CALLBACKS" in perlcall.
POP_MULTICALL;
"PUSH_MULTICALL"
Opening bracket for a lightweight callback. See "LIGHTWEIGHT
CALLBACKS" in perlcall.
PUSH_MULTICALL(CV* the_cv);
Numeric Functions
"Atol"
"DEPRECATED!" It is planned to remove "Atol" from a future release
of Perl. Do not use it for new code; remove it from existing code.
Described in perlhacktips.
Atol(const char * nptr)
"Atoul"
"DEPRECATED!" It is planned to remove "Atoul" from a future release
of Perl. Do not use it for new code; remove it from existing code.
Described in perlhacktips.
Atoul(const char * nptr)
"Drand01"
This macro is to be used to generate uniformly distributed random
numbers over the range [0., 1.[. You may have to supply an 'extern
double drand48();' in your program since SunOS 4.1.3 doesn't provide
you with anything relevant in its headers. See "HAS_DRAND48_PROTO".
double Drand01()
"Gconvert"
This preprocessor macro is defined to convert a floating point
number to a string without a trailing decimal point. This emulates
the behavior of sprintf("%g"), but is sometimes much more efficient.
If gconvert() is not available, but gcvt() drops the trailing
decimal point, then gcvt() is used. If all else fails, a macro
using sprintf("%g") is used. Arguments for the Gconvert macro are:
value, number of digits, whether trailing zeros should be retained,
and the output buffer. The usual values are:
d_Gconvert='gconvert((x),(n),(t),(b))'
d_Gconvert='gcvt((x),(n),(b))'
d_Gconvert='sprintf((b),"%.*g",(n),(x))'
The last two assume trailing zeros should not be kept.
char * Gconvert(double x, Size_t n, bool t, char * b)
"grok_atoUV"
parse a string, looking for a decimal unsigned integer.
On entry, "pv" points to the beginning of the string; "valptr"
points to a UV that will receive the converted value, if found;
"endptr" is either NULL or points to a variable that points to one
byte beyond the point in "pv" that this routine should examine. If
"endptr" is NULL, "pv" is assumed to be NUL-terminated.
Returns FALSE if "pv" doesn't represent a valid unsigned integer
value (with no leading zeros). Otherwise it returns TRUE, and sets
*valptr to that value.
If you constrain the portion of "pv" that is looked at by this
function (by passing a non-NULL "endptr"), and if the initial bytes
of that portion form a valid value, it will return TRUE, setting
*endptr to the byte following the final digit of the value. But if
there is no constraint at what's looked at, all of "pv" must be
valid in order for TRUE to be returned. *endptr is unchanged from
its value on input if FALSE is returned;
The only characters this accepts are the decimal digits '0'..'9'.
As opposed to atoi(3) or strtol(3), "grok_atoUV" does NOT allow
optional leading whitespace, nor negative inputs. If such features
are required, the calling code needs to explicitly implement those.
Note that this function returns FALSE for inputs that would overflow
a UV, or have leading zeros. Thus a single 0 is accepted, but not
00 nor 01, 002, etc.
Background: "atoi" has severe problems with illegal inputs, it
cannot be used for incremental parsing, and therefore should be
avoided "atoi" and "strtol" are also affected by locale settings,
which can also be seen as a bug (global state controlled by user
environment).
bool grok_atoUV(const char *pv, UV *valptr, const char **endptr)
"grok_bin"
converts a string representing a binary number to numeric form.
On entry "start" and *len_p give the string to scan, *flags gives
conversion flags, and "result" should be "NULL" or a pointer to an
NV. The scan stops at the end of the string, or at just before the
first invalid character. Unless "PERL_SCAN_SILENT_ILLDIGIT" is set
in *flags, encountering an invalid character (except NUL) will also
trigger a warning. On return *len_p is set to the length of the
scanned string, and *flags gives output flags.
If the value is <= "UV_MAX" it is returned as a UV, the output flags
are clear, and nothing is written to *result. If the value is >
"UV_MAX", "grok_bin" returns "UV_MAX", sets
"PERL_SCAN_GREATER_THAN_UV_MAX" in the output flags, and writes an
approximation of the correct value into *result (which is an NV; or
the approximation is discarded if "result" is NULL).
The binary number may optionally be prefixed with "0b" or "b" unless
"PERL_SCAN_DISALLOW_PREFIX" is set in *flags on entry.
If "PERL_SCAN_ALLOW_UNDERSCORES" is set in *flags then any or all
pairs of digits may be separated from each other by a single
underscore; also a single leading underscore is accepted.
UV grok_bin(const char *start, STRLEN *len_p, I32 *flags,
NV *result)
"grok_hex"
converts a string representing a hex number to numeric form.
On entry "start" and *len_p give the string to scan, *flags gives
conversion flags, and "result" should be "NULL" or a pointer to an
NV. The scan stops at the end of the string, or at just before the
first invalid character. Unless "PERL_SCAN_SILENT_ILLDIGIT" is set
in *flags, encountering an invalid character (except NUL) will also
trigger a warning. On return *len_p is set to the length of the
scanned string, and *flags gives output flags.
If the value is <= "UV_MAX" it is returned as a UV, the output flags
are clear, and nothing is written to *result. If the value is >
"UV_MAX", "grok_hex" returns "UV_MAX", sets
"PERL_SCAN_GREATER_THAN_UV_MAX" in the output flags, and writes an
approximation of the correct value into *result (which is an NV; or
the approximation is discarded if "result" is NULL).
The hex number may optionally be prefixed with "0x" or "x" unless
"PERL_SCAN_DISALLOW_PREFIX" is set in *flags on entry.
If "PERL_SCAN_ALLOW_UNDERSCORES" is set in *flags then any or all
pairs of digits may be separated from each other by a single
underscore; also a single leading underscore is accepted.
UV grok_hex(const char *start, STRLEN *len_p, I32 *flags,
NV *result)
"grok_infnan"
Helper for grok_number(), accepts various ways of spelling
"infinity" or "not a number", and returns one of the following flag
combinations:
IS_NUMBER_INFINITY
IS_NUMBER_NAN
IS_NUMBER_INFINITY | IS_NUMBER_NEG
IS_NUMBER_NAN | IS_NUMBER_NEG
0
possibly |-ed with "IS_NUMBER_TRAILING".
If an infinity or a not-a-number is recognized, *sp will point to
one byte past the end of the recognized string. If the recognition
fails, zero is returned, and *sp will not move.
int grok_infnan(const char **sp, const char *send)
"grok_number"
Identical to grok_number_flags() with "flags" set to zero.
int grok_number(const char *pv, STRLEN len, UV *valuep)
"grok_number_flags"
Recognise (or not) a number. The type of the number is returned (0
if unrecognised), otherwise it is a bit-ORed combination of
"IS_NUMBER_IN_UV", "IS_NUMBER_GREATER_THAN_UV_MAX",
"IS_NUMBER_NOT_INT", "IS_NUMBER_NEG", "IS_NUMBER_INFINITY",
"IS_NUMBER_NAN" (defined in perl.h).
If the value of the number can fit in a UV, it is returned in
*valuep. "IS_NUMBER_IN_UV" will be set to indicate that *valuep is
valid, "IS_NUMBER_IN_UV" will never be set unless *valuep is valid,
but *valuep may have been assigned to during processing even though
"IS_NUMBER_IN_UV" is not set on return. If "valuep" is "NULL",
"IS_NUMBER_IN_UV" will be set for the same cases as when "valuep" is
non-"NULL", but no actual assignment (or SEGV) will occur.
"IS_NUMBER_NOT_INT" will be set with "IS_NUMBER_IN_UV" if trailing
decimals were seen (in which case *valuep gives the true value
truncated to an integer), and "IS_NUMBER_NEG" if the number is
negative (in which case *valuep holds the absolute value).
"IS_NUMBER_IN_UV" is not set if "e" notation was used or the number
is larger than a UV.
"flags" allows only "PERL_SCAN_TRAILING", which allows for trailing
non-numeric text on an otherwise successful grok, setting
"IS_NUMBER_TRAILING" on the result.
int grok_number_flags(const char *pv, STRLEN len, UV *valuep,
U32 flags)
"GROK_NUMERIC_RADIX"
A synonym for "grok_numeric_radix"
bool GROK_NUMERIC_RADIX(NN const char **sp, NN const char *send)
"grok_numeric_radix"
Scan and skip for a numeric decimal separator (radix).
bool grok_numeric_radix(const char **sp, const char *send)
"grok_oct"
converts a string representing an octal number to numeric form.
On entry "start" and *len_p give the string to scan, *flags gives
conversion flags, and "result" should be "NULL" or a pointer to an
NV. The scan stops at the end of the string, or at just before the
first invalid character. Unless "PERL_SCAN_SILENT_ILLDIGIT" is set
in *flags, encountering an invalid character (except NUL) will also
trigger a warning. On return *len_p is set to the length of the
scanned string, and *flags gives output flags.
If the value is <= "UV_MAX" it is returned as a UV, the output flags
are clear, and nothing is written to *result. If the value is >
"UV_MAX", "grok_oct" returns "UV_MAX", sets
"PERL_SCAN_GREATER_THAN_UV_MAX" in the output flags, and writes an
approximation of the correct value into *result (which is an NV; or
the approximation is discarded if "result" is NULL).
If "PERL_SCAN_ALLOW_UNDERSCORES" is set in *flags then any or all
pairs of digits may be separated from each other by a single
underscore; also a single leading underscore is accepted.
The "PERL_SCAN_DISALLOW_PREFIX" flag is always treated as being set
for this function.
UV grok_oct(const char *start, STRLEN *len_p, I32 *flags,
NV *result)
"isinfnan"
Perl_isinfnan() is a utility function that returns true if the NV
argument is either an infinity or a "NaN", false otherwise. To test
in more detail, use Perl_isinf() and Perl_isnan().
This is also the logical inverse of Perl_isfinite().
bool isinfnan(NV nv)
"my_atof"
"atof"(3), but properly works with Perl locale handling, accepting a
dot radix character always, but also the current locale's radix
character if and only if called from within the lexical scope of a
Perl "use locale" statement.
N.B. "s" must be NUL terminated.
NV my_atof(const char *s)
"my_strtod"
This function is equivalent to the libc strtod() function, and is
available even on platforms that lack plain strtod(). Its return
value is the best available precision depending on platform
capabilities and Configure options.
It properly handles the locale radix character, meaning it expects a
dot except when called from within the scope of "use locale", in
which case the radix character should be that specified by the
current locale.
The synonym Strtod() may be used instead.
NV my_strtod(const char * const s, char **e)
"PERL_ABS"
Typeless "abs" or "fabs", etc. (The usage below indicates it is for
integers, but it works for any type.) Use instead of these, since
the C library ones force their argument to be what it is expecting,
potentially leading to disaster. But also beware that this
evaluates its argument twice, so no "x++".
int PERL_ABS(int x)
"Perl_acos"
"Perl_asin"
"Perl_atan"
"Perl_atan2"
"Perl_ceil"
"Perl_cos"
"Perl_cosh"
"Perl_exp"
"Perl_floor"
"Perl_fmod"
"Perl_frexp"
"Perl_isfinite"
"Perl_isinf"
"Perl_isnan"
"Perl_ldexp"
"Perl_log"
"Perl_log10"
"Perl_modf"
"Perl_pow"
"Perl_sin"
"Perl_sinh"
"Perl_sqrt"
"Perl_tan"
"Perl_tanh"
These perform the corresponding mathematical operation on the
operand(s), using the libc function designed for the task that has
just enough precision for an NV on this platform. If no such
function with sufficient precision exists, the highest precision one
available is used.
NV Perl_acos (NV x)
NV Perl_asin (NV x)
NV Perl_atan (NV x)
NV Perl_atan2 (NV x, NV y)
NV Perl_ceil (NV x)
NV Perl_cos (NV x)
NV Perl_cosh (NV x)
NV Perl_exp (NV x)
NV Perl_floor (NV x)
NV Perl_fmod (NV x, NV y)
NV Perl_frexp (NV x, int *exp)
IV Perl_isfinite(NV x)
IV Perl_isinf (NV x)
IV Perl_isnan (NV x)
NV Perl_ldexp (NV x, int exp)
NV Perl_log (NV x)
NV Perl_log10 (NV x)
NV Perl_modf (NV x, NV *iptr)
NV Perl_pow (NV x, NV y)
NV Perl_sin (NV x)
NV Perl_sinh (NV x)
NV Perl_sqrt (NV x)
NV Perl_tan (NV x)
NV Perl_tanh (NV x)
"Perl_signbit"
NOTE: "Perl_signbit" is experimental and may change or be removed
without notice.
Return a non-zero integer if the sign bit on an NV is set, and 0 if
it is not.
If Configure detects this system has a signbit() that will work with
our NVs, then we just use it via the "#define" in perl.h.
Otherwise, fall back on this implementation. The main use of this
function is catching -0.0.
"Configure" notes: This function is called 'Perl_signbit' instead
of a plain 'signbit' because it is easy to imagine a system having a
signbit() function or macro that doesn't happen to work with our
particular choice of NVs. We shouldn't just re-"#define" "signbit"
as "Perl_signbit" and expect the standard system headers to be
happy. Also, this is a no-context function (no "pTHX_") because
Perl_signbit() is usually re-"#defined" in perl.h as a simple macro
call to the system's signbit(). Users should just always call
Perl_signbit().
int Perl_signbit(NV f)
"PL_hexdigit"
This array, indexed by an integer, converts that value into the
character that represents it. For example, if the input is 8, the
return will be a string whose first character is '8'. What is
actually returned is a pointer into a string. All you are
interested in is the first character of that string. To get
uppercase letters (for the values 10..15), add 16 to the index.
Hence, "PL_hexdigit[11]" is 'b', and "PL_hexdigit[11+16]" is 'B'.
Adding 16 to an index whose representation is '0'..'9' yields the
same as not adding 16. Indices outside the range 0..31 result in
(bad) undedefined behavior.
"READ_XDIGIT"
Returns the value of an ASCII-range hex digit and advances the
string pointer. Behaviour is only well defined when isXDIGIT(*str)
is true.
U8 READ_XDIGIT(char str*)
"scan_bin"
For backwards compatibility. Use "grok_bin" instead.
NV scan_bin(const char *start, STRLEN len, STRLEN *retlen)
"scan_hex"
For backwards compatibility. Use "grok_hex" instead.
NV scan_hex(const char *start, STRLEN len, STRLEN *retlen)
"scan_oct"
For backwards compatibility. Use "grok_oct" instead.
NV scan_oct(const char *start, STRLEN len, STRLEN *retlen)
"seedDrand01"
This symbol defines the macro to be used in seeding the random
number generator (see "Drand01").
void seedDrand01(Rand_seed_t x)
"Strtod"
This is a synonym for "my_strtod".
NV Strtod(NN const char * const s, NULLOK char ** e)
"Strtol"
Platform and configuration independent "strtol". This expands to
the appropriate "strotol"-like function based on the platform and
Configure options>. For example it could expand to "strtoll" or
"strtoq" instead of "strtol".
NV Strtol(NN const char * const s, NULLOK char ** e, int base)
"Strtoul"
Platform and configuration independent "strtoul". This expands to
the appropriate "strotoul"-like function based on the platform and
Configure options>. For example it could expand to "strtoull" or
"strtouq" instead of "strtoul".
NV Strtoul(NN const char * const s, NULLOK char ** e, int base)
Optrees
"alloccopstash"
NOTE: "alloccopstash" is experimental and may change or be removed
without notice.
Available only under threaded builds, this function allocates an
entry in "PL_stashpad" for the stash passed to it.
PADOFFSET alloccopstash(HV *hv)
"BINOP"
Described in perlguts.
"block_end"
Handles compile-time scope exit. "floor" is the savestack index
returned by "block_start", and "seq" is the body of the block.
Returns the block, possibly modified.
OP * block_end(I32 floor, OP *seq)
"block_start"
Handles compile-time scope entry. Arranges for hints to be restored
on block exit and also handles pad sequence numbers to make lexical
variables scope right. Returns a savestack index for use with
"block_end".
int block_start(int full)
"ck_entersub_args_list"
Performs the default fixup of the arguments part of an "entersub" op
tree. This consists of applying list context to each of the
argument ops. This is the standard treatment used on a call marked
with "&", or a method call, or a call through a subroutine
reference, or any other call where the callee can't be identified at
compile time, or a call where the callee has no prototype.
OP * ck_entersub_args_list(OP *entersubop)
"ck_entersub_args_proto"
Performs the fixup of the arguments part of an "entersub" op tree
based on a subroutine prototype. This makes various modifications
to the argument ops, from applying context up to inserting "refgen"
ops, and checking the number and syntactic types of arguments, as
directed by the prototype. This is the standard treatment used on a
subroutine call, not marked with "&", where the callee can be
identified at compile time and has a prototype.
"protosv" supplies the subroutine prototype to be applied to the
call. It may be a normal defined scalar, of which the string value
will be used. Alternatively, for convenience, it may be a
subroutine object (a "CV*" that has been cast to "SV*") which has a
prototype. The prototype supplied, in whichever form, does not need
to match the actual callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by
having an unacceptable number of arguments, a valid op tree is
returned anyway. The error is reflected in the parser state,
normally resulting in a single exception at the top level of parsing
which covers all the compilation errors that occurred. In the error
message, the callee is referred to by the name defined by the
"namegv" parameter.
OP * ck_entersub_args_proto(OP *entersubop, GV *namegv,
SV *protosv)
"ck_entersub_args_proto_or_list"
Performs the fixup of the arguments part of an "entersub" op tree
either based on a subroutine prototype or using default list-context
processing. This is the standard treatment used on a subroutine
call, not marked with "&", where the callee can be identified at
compile time.
"protosv" supplies the subroutine prototype to be applied to the
call, or indicates that there is no prototype. It may be a normal
scalar, in which case if it is defined then the string value will be
used as a prototype, and if it is undefined then there is no
prototype. Alternatively, for convenience, it may be a subroutine
object (a "CV*" that has been cast to "SV*"), of which the prototype
will be used if it has one. The prototype (or lack thereof)
supplied, in whichever form, does not need to match the actual
callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by
having an unacceptable number of arguments, a valid op tree is
returned anyway. The error is reflected in the parser state,
normally resulting in a single exception at the top level of parsing
which covers all the compilation errors that occurred. In the error
message, the callee is referred to by the name defined by the
"namegv" parameter.
OP * ck_entersub_args_proto_or_list(OP *entersubop, GV *namegv,
SV *protosv)
"cv_const_sv"
If "cv" is a constant sub eligible for inlining, returns the
constant value returned by the sub. Otherwise, returns "NULL".
Constant subs can be created with "newCONSTSUB" or as described in
"Constant Functions" in perlsub.
SV * cv_const_sv(const CV * const cv)
"cv_get_call_checker"
The original form of "cv_get_call_checker_flags", which does not
return checker flags. When using a checker function returned by
this function, it is only safe to call it with a genuine GV as its
"namegv" argument.
void cv_get_call_checker(CV *cv, Perl_call_checker *ckfun_p,
SV **ckobj_p)
"cv_get_call_checker_flags"
Retrieves the function that will be used to fix up a call to "cv".
Specifically, the function is applied to an "entersub" op tree for a
subroutine call, not marked with "&", where the callee can be
identified at compile time as "cv".
The C-level function pointer is returned in *ckfun_p, an SV argument
for it is returned in *ckobj_p, and control flags are returned in
*ckflags_p. The function is intended to be called in this manner:
entersubop = (*ckfun_p)(aTHX_ entersubop, namegv, (*ckobj_p));
In this call, "entersubop" is a pointer to the "entersub" op, which
may be replaced by the check function, and "namegv" supplies the
name that should be used by the check function to refer to the
callee of the "entersub" op if it needs to emit any diagnostics. It
is permitted to apply the check function in non-standard situations,
such as to a call to a different subroutine or to a method call.
"namegv" may not actually be a GV. If the "CALL_CHECKER_REQUIRE_GV"
bit is clear in *ckflags_p, it is permitted to pass a CV or other SV
instead, anything that can be used as the first argument to
"cv_name". If the "CALL_CHECKER_REQUIRE_GV" bit is set in
*ckflags_p then the check function requires "namegv" to be a genuine
GV.
By default, the check function is
Perl_ck_entersub_args_proto_or_list, the SV parameter is "cv"
itself, and the "CALL_CHECKER_REQUIRE_GV" flag is clear. This
implements standard prototype processing. It can be changed, for a
particular subroutine, by "cv_set_call_checker_flags".
If the "CALL_CHECKER_REQUIRE_GV" bit is set in "gflags" then it
indicates that the caller only knows about the genuine GV version of
"namegv", and accordingly the corresponding bit will always be set
in *ckflags_p, regardless of the check function's recorded
requirements. If the "CALL_CHECKER_REQUIRE_GV" bit is clear in
"gflags" then it indicates the caller knows about the possibility of
passing something other than a GV as "namegv", and accordingly the
corresponding bit may be either set or clear in *ckflags_p,
indicating the check function's recorded requirements.
"gflags" is a bitset passed into "cv_get_call_checker_flags", in
which only the "CALL_CHECKER_REQUIRE_GV" bit currently has a defined
meaning (for which see above). All other bits should be clear.
void cv_get_call_checker_flags(CV *cv, U32 gflags,
Perl_call_checker *ckfun_p,
SV **ckobj_p, U32 *ckflags_p)
"cv_set_call_checker"
The original form of "cv_set_call_checker_flags", which passes it
the "CALL_CHECKER_REQUIRE_GV" flag for backward-compatibility. The
effect of that flag setting is that the check function is guaranteed
to get a genuine GV as its "namegv" argument.
void cv_set_call_checker(CV *cv, Perl_call_checker ckfun,
SV *ckobj)
"cv_set_call_checker_flags"
Sets the function that will be used to fix up a call to "cv".
Specifically, the function is applied to an "entersub" op tree for a
subroutine call, not marked with "&", where the callee can be
identified at compile time as "cv".
The C-level function pointer is supplied in "ckfun", an SV argument
for it is supplied in "ckobj", and control flags are supplied in
"ckflags". The function should be defined like this:
STATIC OP * ckfun(pTHX_ OP *op, GV *namegv, SV *ckobj)
It is intended to be called in this manner:
entersubop = ckfun(aTHX_ entersubop, namegv, ckobj);
In this call, "entersubop" is a pointer to the "entersub" op, which
may be replaced by the check function, and "namegv" supplies the
name that should be used by the check function to refer to the
callee of the "entersub" op if it needs to emit any diagnostics. It
is permitted to apply the check function in non-standard situations,
such as to a call to a different subroutine or to a method call.
"namegv" may not actually be a GV. For efficiency, perl may pass a
CV or other SV instead. Whatever is passed can be used as the first
argument to "cv_name". You can force perl to pass a GV by including
"CALL_CHECKER_REQUIRE_GV" in the "ckflags".
"ckflags" is a bitset, in which only the "CALL_CHECKER_REQUIRE_GV"
bit currently has a defined meaning (for which see above). All
other bits should be clear.
The current setting for a particular CV can be retrieved by
"cv_get_call_checker_flags".
void cv_set_call_checker_flags(CV *cv, Perl_call_checker ckfun,
SV *ckobj, U32 ckflags)
"finalize_optree"
This function finalizes the optree. Should be called directly after
the complete optree is built. It does some additional checking
which can't be done in the normal "ck_"xxx functions and makes the
tree thread-safe.
void finalize_optree(OP *o)
"forbid_outofblock_ops"
NOTE: "forbid_outofblock_ops" is experimental and may change or be
removed without notice.
Checks an optree that implements a block, to ensure there are no
control-flow ops that attempt to leave the block. Any "OP_RETURN"
is forbidden, as is any "OP_GOTO". Loops are analysed, so any LOOPEX
op ("OP_NEXT", "OP_LAST" or "OP_REDO") that affects a loop that
contains it within the block are permitted, but those that do not
are forbidden.
If any of these forbidden constructions are detected, an exception
is thrown by using the op name and the blockname argument to
construct a suitable message.
This function alone is not sufficient to ensure the optree does not
perform any of these forbidden activities during runtime, as it
might call a different function that performs a non-local LOOPEX, or
a string-eval() that performs a "goto", or various other things. It
is intended purely as a compile-time check for those that could be
detected statically. Additional runtime checks may be required
depending on the circumstance it is used for.
Note currently that all "OP_GOTO" ops are forbidden, even in cases
where they might otherwise be safe to execute. This may be
permitted in a later version.
void forbid_outofblock_ops(OP *o, const char *blockname)
"LINKLIST"
Given the root of an optree, link the tree in execution order using
the "op_next" pointers and return the first op executed. If this
has already been done, it will not be redone, and "o->op_next" will
be returned. If "o->op_next" is not already set, "o" should be at
least an "UNOP".
OP* LINKLIST(OP *o)
"LISTOP"
Described in perlguts.
"LOGOP"
Described in perlguts.
"LOOP"
Described in perlguts.
"newANONATTRSUB"
Construct a nameless (anonymous) Perl subroutine, also performing
some surrounding jobs.
This is the same as ""newATTRSUB_x"" in perlintern with its
"o_is_gv" parameter set to FALSE, and its "o" parameter to NULL.
For more details, see ""newATTRSUB_x"" in perlintern.
OP * newANONATTRSUB(I32 floor, OP *proto, OP *attrs, OP *block)
"newANONHASH"
Constructs, checks, and returns an anonymous hash op.
OP * newANONHASH(OP *o)
"newANONLIST"
Constructs, checks, and returns an anonymous list op.
OP * newANONLIST(OP *o)
"newANONSUB"
Construct a nameless (anonymous) Perl subroutine without attributes,
also performing some surrounding jobs.
This is the same as ""newATTRSUB_x"" in perlintern with its
"o_is_gv" parameter set to FALSE, and its "o" and "attrs" parameters
to NULL. For more details, see ""newATTRSUB_x"" in perlintern.
OP * newANONSUB(I32 floor, OP *proto, OP *block)
"newARGDEFELEMOP"
Constructs and returns a new "OP_ARGDEFELEM" op which provides a
defaulting expression given by "expr" for the signature parameter at
the index given by "argindex". The expression optree is consumed by
this function and becomes part of the returned optree.
OP * newARGDEFELEMOP(I32 flags, OP *expr, I32 argindex)
"newASSIGNOP"
Constructs, checks, and returns an assignment op. "left" and
"right" supply the parameters of the assignment; they are consumed
by this function and become part of the constructed op tree.
If "optype" is "OP_ANDASSIGN", "OP_ORASSIGN", or "OP_DORASSIGN",
then a suitable conditional optree is constructed. If "optype" is
the opcode of a binary operator, such as "OP_BIT_OR", then an op is
constructed that performs the binary operation and assigns the
result to the left argument. Either way, if "optype" is non-zero
then "flags" has no effect.
If "optype" is zero, then a plain scalar or list assignment is
constructed. Which type of assignment it is is automatically
determined. "flags" gives the eight bits of "op_flags", except that
"OPf_KIDS" will be set automatically, and, shifted up eight bits,
the eight bits of "op_private", except that the bit with value 1 or
2 is automatically set as required.
OP * newASSIGNOP(I32 flags, OP *left, I32 optype, OP *right)
"newATTRSUB"
Construct a Perl subroutine, also performing some surrounding jobs,
returning a pointer to the constructed subroutine.
This is the same as ""newATTRSUB_x"" in perlintern with its
"o_is_gv" parameter set to FALSE. This means that if "o" is null,
the new sub will be anonymous; otherwise the name will be derived
from "o" in the way described (as with all other details) in
""newATTRSUB_x"" in perlintern.
CV * newATTRSUB(I32 floor, OP *o, OP *proto, OP *attrs,
OP *block)
"newAVREF"
Constructs, checks, and returns an arrary reference op.
OP * newAVREF(OP *o)
"newBINOP"
Constructs, checks, and returns an op of any binary type. "type" is
the opcode. "flags" gives the eight bits of "op_flags", except that
"OPf_KIDS" will be set automatically, and, shifted up eight bits,
the eight bits of "op_private", except that the bit with value 1 or
2 is automatically set as required. "first" and "last" supply up to
two ops to be the direct children of the binary op; they are
consumed by this function and become part of the constructed op
tree.
OP * newBINOP(I32 type, I32 flags, OP *first, OP *last)
"newCONDOP"
Constructs, checks, and returns a conditional-expression
("cond_expr") op. "flags" gives the eight bits of "op_flags",
except that "OPf_KIDS" will be set automatically, and, shifted up
eight bits, the eight bits of "op_private", except that the bit with
value 1 is automatically set. "first" supplies the expression
selecting between the two branches, and "trueop" and "falseop"
supply the branches; they are consumed by this function and become
part of the constructed op tree.
OP * newCONDOP(I32 flags, OP *first, OP *trueop, OP *falseop)
"newCONSTSUB"
"newCONSTSUB_flags"
Construct a constant subroutine, also performing some surrounding
jobs. A scalar constant-valued subroutine is eligible for inlining
at compile-time, and in Perl code can be created by
"sub FOO () { 123 }". Other kinds of constant subroutine have other
treatment.
The subroutine will have an empty prototype and will ignore any
arguments when called. Its constant behaviour is determined by
"sv". If "sv" is null, the subroutine will yield an empty list. If
"sv" points to a scalar, the subroutine will always yield that
scalar. If "sv" points to an array, the subroutine will always
yield a list of the elements of that array in list context, or the
number of elements in the array in scalar context. This function
takes ownership of one counted reference to the scalar or array, and
will arrange for the object to live as long as the subroutine does.
If "sv" points to a scalar then the inlining assumes that the value
of the scalar will never change, so the caller must ensure that the
scalar is not subsequently written to. If "sv" points to an array
then no such assumption is made, so it is ostensibly safe to mutate
the array or its elements, but whether this is really supported has
not been determined.
The subroutine will have "CvFILE" set according to "PL_curcop".
Other aspects of the subroutine will be left in their default state.
The caller is free to mutate the subroutine beyond its initial state
after this function has returned.
If "name" is null then the subroutine will be anonymous, with its
"CvGV" referring to an "__ANON__" glob. If "name" is non-null then
the subroutine will be named accordingly, referenced by the
appropriate glob.
"name" is a string, giving a sigilless symbol name. For
"/newCONSTSUB", "name" is NUL-terminated, interpreted as Latin-1.
For "/newCONSTSUB_flags", "name" has length "len" bytes, hence may
contain embedded NULs. It is interpreted as UTF-8 if "flags" has
the "SVf_UTF8" bit set, and Latin-1 otherwise. "flags" should not
have bits set other than "SVf_UTF8".
The name may be either qualified or unqualified. If the name is
unqualified then it defaults to being in the stash specified by
"stash" if that is non-null, or to "PL_curstash" if "stash" is null.
The symbol is always added to the stash if necessary, with
"GV_ADDMULTI" semantics.
If there is already a subroutine of the specified name, then the new
sub will replace the existing one in the glob. A warning may be
generated about the redefinition.
If the subroutine has one of a few special names, such as "BEGIN" or
"END", then it will be claimed by the appropriate queue for
automatic running of phase-related subroutines. In this case the
relevant glob will be left not containing any subroutine, even if it
did contain one before. Execution of the subroutine will likely be
a no-op, unless "sv" was a tied array or the caller modified the
subroutine in some interesting way before it was executed. In the
case of "BEGIN", the treatment is buggy: the sub will be executed
when only half built, and may be deleted prematurely, possibly
causing a crash.
The function returns a pointer to the constructed subroutine. If
the sub is anonymous then ownership of one counted reference to the
subroutine is transferred to the caller. If the sub is named then
the caller does not get ownership of a reference. In most such
cases, where the sub has a non-phase name, the sub will be alive at
the point it is returned by virtue of being contained in the glob
that names it. A phase-named subroutine will usually be alive by
virtue of the reference owned by the phase's automatic run queue. A
"BEGIN" subroutine may have been destroyed already by the time this
function returns, but currently bugs occur in that case before the
caller gets control. It is the caller's responsibility to ensure
that it knows which of these situations applies.
CV * newCONSTSUB (HV *stash, const char *name, SV *sv)
CV * newCONSTSUB_flags(HV *stash, const char *name, STRLEN len,
U32 flags, SV *sv)
"newCVREF"
Constructs, checks, and returns a code reference op.
OP * newCVREF(I32 flags, OP *o)
"newDEFEROP"
NOTE: "newDEFEROP" is experimental and may change or be removed
without notice.
Constructs and returns a deferred-block statement that implements
the "defer" semantics. The "block" optree is consumed by this
function and becomes part of the returned optree.
The "flags" argument carries additional flags to set on the returned
op, including the "op_private" field.
OP * newDEFEROP(I32 flags, OP *block)
"newDEFSVOP"
Constructs and returns an op to access $_.
OP * newDEFSVOP()
"newFOROP"
Constructs, checks, and returns an op tree expressing a "foreach"
loop (iteration through a list of values). This is a heavyweight
loop, with structure that allows exiting the loop by "last" and
suchlike.
"sv" optionally supplies the variable(s) that will be aliased to
each item in turn; if null, it defaults to $_. "expr" supplies the
list of values to iterate over. "block" supplies the main body of
the loop, and "cont" optionally supplies a "continue" block that
operates as a second half of the body. All of these optree inputs
are consumed by this function and become part of the constructed op
tree.
"flags" gives the eight bits of "op_flags" for the "leaveloop" op
and, shifted up eight bits, the eight bits of "op_private" for the
"leaveloop" op, except that (in both cases) some bits will be set
automatically.
OP * newFOROP(I32 flags, OP *sv, OP *expr, OP *block, OP *cont)
"newGIVENOP"
Constructs, checks, and returns an op tree expressing a "given"
block. "cond" supplies the expression to whose value $_ will be
locally aliased, and "block" supplies the body of the "given"
construct; they are consumed by this function and become part of the
constructed op tree. "defsv_off" must be zero (it used to identity
the pad slot of lexical $_).
OP * newGIVENOP(OP *cond, OP *block, PADOFFSET defsv_off)
"newGVOP"
Constructs, checks, and returns an op of any type that involves an
embedded reference to a GV. "type" is the opcode. "flags" gives
the eight bits of "op_flags". "gv" identifies the GV that the op
should reference; calling this function does not transfer ownership
of any reference to it.
OP * newGVOP(I32 type, I32 flags, GV *gv)
"newGVREF"
Constructs, checks, and returns a glob reference op.
OP * newGVREF(I32 type, OP *o)
"newHVREF"
Constructs, checks, and returns a hash reference op.
OP * newHVREF(OP *o)
"newLISTOP"
Constructs, checks, and returns an op of any list type. "type" is
the opcode. "flags" gives the eight bits of "op_flags", except that
"OPf_KIDS" will be set automatically if required. "first" and
"last" supply up to two ops to be direct children of the list op;
they are consumed by this function and become part of the
constructed op tree.
For most list operators, the check function expects all the kid ops
to be present already, so calling "newLISTOP(OP_JOIN, ...)" (e.g.)
is not appropriate. What you want to do in that case is create an
op of type "OP_LIST", append more children to it, and then call
"op_convert_list". See "op_convert_list" for more information.
If a compiletime-known fixed list of child ops is required, the
"newLISTOPn" function can be used as a convenient shortcut, avoiding
the need to create a temporary plain "OP_LIST" in a new variable.
OP * newLISTOP(I32 type, I32 flags, OP *first, OP *last)
"newLISTOPn"
Constructs, checks, and returns an op of any list type. "type" is
the opcode. "flags" gives the eight bits of "op_flags", except that
"OPf_KIDS" will be set automatically if required. The variable
number of arguments after "flags" must all be OP pointers,
terminated by a final "NULL" pointer. These will all be consumed as
direct children of the list op and become part of the constructed op
tree.
Do not forget to end the arguments list with a "NULL" pointer.
This function is useful as a shortcut to performing the sequence of
newLISTOP(), op_append_elem() on each element and final
op_convert_list() in the case where a compiletime-known fixed
sequence of child ops is required. If a variable number of elements
are required, or for splicing in an entire sub-list of child ops,
see instead "newLISTOP" and "op_convert_list".
OP * newLISTOPn(I32 type, I32 flags, ...)
"newLOGOP"
Constructs, checks, and returns a logical (flow control) op. "type"
is the opcode. "flags" gives the eight bits of "op_flags", except
that "OPf_KIDS" will be set automatically, and, shifted up eight
bits, the eight bits of "op_private", except that the bit with value
1 is automatically set. "first" supplies the expression controlling
the flow, and "other" supplies the side (alternate) chain of ops;
they are consumed by this function and become part of the
constructed op tree.
OP * newLOGOP(I32 optype, I32 flags, OP *first, OP *other)
"newLOOPEX"
Constructs, checks, and returns a loop-exiting op (such as "goto" or
"last"). "type" is the opcode. "label" supplies the parameter
determining the target of the op; it is consumed by this function
and becomes part of the constructed op tree.
OP * newLOOPEX(I32 type, OP *label)
"newLOOPOP"
Constructs, checks, and returns an op tree expressing a loop. This
is only a loop in the control flow through the op tree; it does not
have the heavyweight loop structure that allows exiting the loop by
"last" and suchlike. "flags" gives the eight bits of "op_flags" for
the top-level op, except that some bits will be set automatically as
required. "expr" supplies the expression controlling loop
iteration, and "block" supplies the body of the loop; they are
consumed by this function and become part of the constructed op
tree. "debuggable" is currently unused and should always be 1.
OP * newLOOPOP(I32 flags, I32 debuggable, OP *expr, OP *block)
"newMETHOP"
Constructs, checks, and returns an op of method type with a method
name evaluated at runtime. "type" is the opcode. "flags" gives the
eight bits of "op_flags", except that "OPf_KIDS" will be set
automatically, and, shifted up eight bits, the eight bits of
"op_private", except that the bit with value 1 is automatically set.
"dynamic_meth" supplies an op which evaluates method name; it is
consumed by this function and become part of the constructed op
tree. Supported optypes: "OP_METHOD".
OP * newMETHOP(I32 type, I32 flags, OP *dynamic_meth)
"newMETHOP_named"
Constructs, checks, and returns an op of method type with a constant
method name. "type" is the opcode. "flags" gives the eight bits of
"op_flags", and, shifted up eight bits, the eight bits of
"op_private". "const_meth" supplies a constant method name; it must
be a shared COW string. Supported optypes: "OP_METHOD_NAMED".
OP * newMETHOP_named(I32 type, I32 flags, SV * const_meth)
"newNULLLIST"
Constructs, checks, and returns a new "stub" op, which represents an
empty list expression.
OP * newNULLLIST()
"newOP"
Constructs, checks, and returns an op of any base type (any type
that has no extra fields). "type" is the opcode. "flags" gives the
eight bits of "op_flags", and, shifted up eight bits, the eight bits
of "op_private".
OP * newOP(I32 optype, I32 flags)
"newPADOP"
Constructs, checks, and returns an op of any type that involves a
reference to a pad element. "type" is the opcode. "flags" gives
the eight bits of "op_flags". A pad slot is automatically
allocated, and is populated with "sv"; this function takes ownership
of one reference to it.
This function only exists if Perl has been compiled to use ithreads.
OP * newPADOP(I32 type, I32 flags, SV *sv)
"newPMOP"
Constructs, checks, and returns an op of any pattern matching type.
"type" is the opcode. "flags" gives the eight bits of "op_flags"
and, shifted up eight bits, the eight bits of "op_private".
OP * newPMOP(I32 type, I32 flags)
"newPVOP"
Constructs, checks, and returns an op of any type that involves an
embedded C-level pointer (PV). "type" is the opcode. "flags" gives
the eight bits of "op_flags". "pv" supplies the C-level pointer.
Depending on the op type, the memory referenced by "pv" may be freed
when the op is destroyed. If the op is of a freeing type, "pv" must
have been allocated using "PerlMemShared_malloc".
OP * newPVOP(I32 type, I32 flags, char *pv)
"newRANGE"
Constructs and returns a "range" op, with subordinate "flip" and
"flop" ops. "flags" gives the eight bits of "op_flags" for the
"flip" op and, shifted up eight bits, the eight bits of "op_private"
for both the "flip" and "range" ops, except that the bit with value
1 is automatically set. "left" and "right" supply the expressions
controlling the endpoints of the range; they are consumed by this
function and become part of the constructed op tree.
OP * newRANGE(I32 flags, OP *left, OP *right)
"newSLICEOP"
Constructs, checks, and returns an "lslice" (list slice) op.
"flags" gives the eight bits of "op_flags", except that "OPf_KIDS"
will be set automatically, and, shifted up eight bits, the eight
bits of "op_private", except that the bit with value 1 or 2 is
automatically set as required. "listval" and "subscript" supply the
parameters of the slice; they are consumed by this function and
become part of the constructed op tree.
OP * newSLICEOP(I32 flags, OP *subscript, OP *listop)
"newSTATEOP"
Constructs a state op (COP). The state op is normally a "nextstate"
op, but will be a "dbstate" op if debugging is enabled for
currently-compiled code. The state op is populated from "PL_curcop"
(or "PL_compiling"). If "label" is non-null, it supplies the name
of a label to attach to the state op; this function takes ownership
of the memory pointed at by "label", and will free it. "flags"
gives the eight bits of "op_flags" for the state op.
If "o" is null, the state op is returned. Otherwise the state op is
combined with "o" into a "lineseq" list op, which is returned. "o"
is consumed by this function and becomes part of the returned op
tree.
OP * newSTATEOP(I32 flags, char *label, OP *o)
"newSUB"
Construct a Perl subroutine without attributes, and also performing
some surrounding jobs, returning a pointer to the constructed
subroutine.
This is the same as ""newATTRSUB_x"" in perlintern with its
"o_is_gv" parameter set to FALSE, and its "attrs" parameter to NULL.
This means that if "o" is null, the new sub will be anonymous;
otherwise the name will be derived from "o" in the way described (as
with all other details) in ""newATTRSUB_x"" in perlintern.
CV * newSUB(I32 floor, OP *o, OP *proto, OP *block)
"newSVOP"
Constructs, checks, and returns an op of any type that involves an
embedded SV. "type" is the opcode. "flags" gives the eight bits of
"op_flags". "sv" gives the SV to embed in the op; this function
takes ownership of one reference to it.
OP * newSVOP(I32 type, I32 flags, SV *sv)
"newSVREF"
Constructs, checks, and returns a scalar reference op.
OP * newSVREF(OP *o)
"newTRYCATCHOP"
NOTE: "newTRYCATCHOP" is experimental and may change or be removed
without notice.
Constructs and returns a conditional execution statement that
implements the "try"/"catch" semantics. First the op tree in
"tryblock" is executed, inside a context that traps exceptions. If
an exception occurs then the optree in "catchblock" is executed,
with the trapped exception set into the lexical variable given by
"catchvar" (which must be an op of type "OP_PADSV"). All the
optrees are consumed by this function and become part of the
returned op tree.
The "flags" argument is currently ignored.
OP * newTRYCATCHOP(I32 flags, OP *tryblock, OP *catchvar,
OP *catchblock)
"newUNOP"
Constructs, checks, and returns an op of any unary type. "type" is
the opcode. "flags" gives the eight bits of "op_flags", except that
"OPf_KIDS" will be set automatically if required, and, shifted up
eight bits, the eight bits of "op_private", except that the bit with
value 1 is automatically set. "first" supplies an optional op to be
the direct child of the unary op; it is consumed by this function
and become part of the constructed op tree.
OP * newUNOP(I32 type, I32 flags, OP *first)
"newUNOP_AUX"
Similar to "newUNOP", but creates an "UNOP_AUX" struct instead, with
"op_aux" initialised to "aux"
OP * newUNOP_AUX(I32 type, I32 flags, OP *first,
UNOP_AUX_item *aux)
"newWHENOP"
Constructs, checks, and returns an op tree expressing a "when"
block. "cond" supplies the test expression, and "block" supplies
the block that will be executed if the test evaluates to true; they
are consumed by this function and become part of the constructed op
tree. "cond" will be interpreted DWIMically, often as a comparison
against $_, and may be null to generate a "default" block.
OP * newWHENOP(OP *cond, OP *block)
"newWHILEOP"
Constructs, checks, and returns an op tree expressing a "while"
loop. This is a heavyweight loop, with structure that allows
exiting the loop by "last" and suchlike.
"loop" is an optional preconstructed "enterloop" op to use in the
loop; if it is null then a suitable op will be constructed
automatically. "expr" supplies the loop's controlling expression.
"block" supplies the main body of the loop, and "cont" optionally
supplies a "continue" block that operates as a second half of the
body. All of these optree inputs are consumed by this function and
become part of the constructed op tree.
"flags" gives the eight bits of "op_flags" for the "leaveloop" op
and, shifted up eight bits, the eight bits of "op_private" for the
"leaveloop" op, except that (in both cases) some bits will be set
automatically. "debuggable" is currently unused and should always
be 1. "has_my" can be supplied as true to force the loop body to be
enclosed in its own scope.
OP * newWHILEOP(I32 flags, I32 debuggable, LOOP *loop, OP *expr,
OP *block, OP *cont, I32 has_my)
"newXS"
Used by "xsubpp" to hook up XSUBs as Perl subs. "filename" needs to
be static storage, as it is used directly as CvFILE(), without a
copy being made.
"OA_BASEOP"
"OA_BINOP"
"OA_COP"
"OA_LISTOP"
"OA_LOGOP"
"OA_LOOP"
"OA_PADOP"
"OA_PMOP"
"OA_PVOP_OR_SVOP"
"OA_SVOP"
"OA_UNOP"
Described in perlguts.
"OP"
Described in perlguts.
"op_append_elem"
Append an item to the list of ops contained directly within a list-
type op, returning the lengthened list. "first" is the list-type
op, and "last" is the op to append to the list. "optype" specifies
the intended opcode for the list. If "first" is not already a list
of the right type, it will be upgraded into one. If either "first"
or "last" is null, the other is returned unchanged.
OP * op_append_elem(I32 optype, OP *first, OP *last)
"op_append_list"
Concatenate the lists of ops contained directly within two list-type
ops, returning the combined list. "first" and "last" are the list-
type ops to concatenate. "optype" specifies the intended opcode for
the list. If either "first" or "last" is not already a list of the
right type, it will be upgraded into one. If either "first" or
"last" is null, the other is returned unchanged.
OP * op_append_list(I32 optype, OP *first, OP *last)
"OP_CLASS"
Return the class of the provided OP: that is, which of the *OP
structures it uses. For core ops this currently gets the
information out of "PL_opargs", which does not always accurately
reflect the type used; in v5.26 onwards, see also the function
"op_class" which can do a better job of determining the used type.
For custom ops the type is returned from the registration, and it is
up to the registree to ensure it is accurate. The value returned
will be one of the "OA_"* constants from op.h.
U32 OP_CLASS(OP *o)
"op_contextualize"
Applies a syntactic context to an op tree representing an
expression. "o" is the op tree, and "context" must be "G_SCALAR",
"G_LIST", or "G_VOID" to specify the context to apply. The modified
op tree is returned.
OP * op_contextualize(OP *o, I32 context)
"op_convert_list"
Converts "o" into a list op if it is not one already, and then
converts it into the specified "type", calling its check function,
allocating a target if it needs one, and folding constants.
A list-type op is usually constructed one kid at a time via
"newLISTOP", "op_prepend_elem" and "op_append_elem". Then finally
it is passed to "op_convert_list" to make it the right type.
OP * op_convert_list(I32 optype, I32 flags, OP *o)
"OP_DESC"
Return a short description of the provided OP.
const char * OP_DESC(OP *o)
"op_force_list"
Promotes o and any siblings to be an "OP_LIST" if it is not already.
If a new "OP_LIST" op was created, its first child will be
"OP_PUSHMARK". The returned node itself will be nulled, leaving
only its children.
This is often what you want to do before putting the optree into
list context; as
o = op_contextualize(op_force_list(o), G_LIST);
OP * op_force_list(OP *o)
"op_free"
Free an op and its children. Only use this when an op is no longer
linked to from any optree.
Remember that any op with "OPf_KIDS" set is expected to have a valid
"op_first" pointer. If you are attempting to free an op but
preserve its child op, make sure to clear that flag before calling
op_free(). For example:
OP *kid = o->op_first; o->op_first = NULL;
o->op_flags &= ~OPf_KIDS;
op_free(o);
void op_free(OP *arg)
"OpHAS_SIBLING"
Returns true if "o" has a sibling
bool OpHAS_SIBLING(OP *o)
"OpLASTSIB_set"
Marks "o" as having no further siblings and marks o as having the
specified parent. See also "OpMORESIB_set" and "OpMAYBESIB_set". For
a higher-level interface, see "op_sibling_splice".
void OpLASTSIB_set(OP *o, OP *parent)
"op_linklist"
This function is the implementation of the "LINKLIST" macro. It
should not be called directly.
OP * op_linklist(OP *o)
"op_lvalue"
NOTE: "op_lvalue" is experimental and may change or be removed
without notice.
Propagate lvalue ("modifiable") context to an op and its children.
"type" represents the context type, roughly based on the type of op
that would do the modifying, although local() is represented by
"OP_NULL", because it has no op type of its own (it is signalled by
a flag on the lvalue op).
This function detects things that can't be modified, such as "$x+1",
and generates errors for them. For example, "$x+1 = 2" would cause
it to be called with an op of type "OP_ADD" and a "type" argument of
"OP_SASSIGN".
It also flags things that need to behave specially in an lvalue
context, such as "$$x = 5" which might have to vivify a reference in
$x.
OP * op_lvalue(OP *o, I32 type)
"OpMAYBESIB_set"
Conditionally does "OpMORESIB_set" or "OpLASTSIB_set" depending on
whether "sib" is non-null. For a higher-level interface, see
"op_sibling_splice".
void OpMAYBESIB_set(OP *o, OP *sib, OP *parent)
"OpMORESIB_set"
Sets the sibling of "o" to the non-zero value "sib". See also
"OpLASTSIB_set" and "OpMAYBESIB_set". For a higher-level interface,
see "op_sibling_splice".
void OpMORESIB_set(OP *o, OP *sib)
"OP_NAME"
Return the name of the provided OP. For core ops this looks up the
name from the op_type; for custom ops from the op_ppaddr.
const char * OP_NAME(OP *o)
"op_null"
Neutralizes an op when it is no longer needed, but is still linked
to from other ops.
void op_null(OP *o)
"op_parent"
Returns the parent OP of "o", if it has a parent. Returns "NULL"
otherwise.
OP * op_parent(OP *o)
"op_prepend_elem"
Prepend an item to the list of ops contained directly within a list-
type op, returning the lengthened list. "first" is the op to
prepend to the list, and "last" is the list-type op. "optype"
specifies the intended opcode for the list. If "last" is not
already a list of the right type, it will be upgraded into one. If
either "first" or "last" is null, the other is returned unchanged.
OP * op_prepend_elem(I32 optype, OP *first, OP *last)
"op_scope"
NOTE: "op_scope" is experimental and may change or be removed
without notice.
Wraps up an op tree with some additional ops so that at runtime a
dynamic scope will be created. The original ops run in the new
dynamic scope, and then, provided that they exit normally, the scope
will be unwound. The additional ops used to create and unwind the
dynamic scope will normally be an "enter"/"leave" pair, but a
"scope" op may be used instead if the ops are simple enough to not
need the full dynamic scope structure.
OP * op_scope(OP *o)
"OpSIBLING"
Returns the sibling of "o", or "NULL" if there is no sibling
OP* OpSIBLING(OP *o)
"op_sibling_splice"
A general function for editing the structure of an existing chain of
op_sibling nodes. By analogy with the perl-level splice() function,
allows you to delete zero or more sequential nodes, replacing them
with zero or more different nodes. Performs the necessary
op_first/op_last housekeeping on the parent node and op_sibling
manipulation on the children. The last deleted node will be marked
as the last node by updating the op_sibling/op_sibparent or
op_moresib field as appropriate.
Note that op_next is not manipulated, and nodes are not freed; that
is the responsibility of the caller. It also won't create a new
list op for an empty list etc; use higher-level functions like
op_append_elem() for that.
"parent" is the parent node of the sibling chain. It may passed as
"NULL" if the splicing doesn't affect the first or last op in the
chain.
"start" is the node preceding the first node to be spliced. Node(s)
following it will be deleted, and ops will be inserted after it. If
it is "NULL", the first node onwards is deleted, and nodes are
inserted at the beginning.
"del_count" is the number of nodes to delete. If zero, no nodes are
deleted. If -1 or greater than or equal to the number of remaining
kids, all remaining kids are deleted.
"insert" is the first of a chain of nodes to be inserted in place of
the nodes. If "NULL", no nodes are inserted.
The head of the chain of deleted ops is returned, or "NULL" if no
ops were deleted.
For example:
action before after returns
------ ----- ----- -------
P P
splice(P, A, 2, X-Y-Z) | | B-C
A-B-C-D A-X-Y-Z-D
P P
splice(P, NULL, 1, X-Y) | | A
A-B-C-D X-Y-B-C-D
P P
splice(P, NULL, 3, NULL) | | A-B-C
A-B-C-D D
P P
splice(P, B, 0, X-Y) | | NULL
A-B-C-D A-B-X-Y-C-D
For lower-level direct manipulation of "op_sibparent" and
"op_moresib", see "OpMORESIB_set", "OpLASTSIB_set",
"OpMAYBESIB_set".
OP * op_sibling_splice(OP *parent, OP *start, int del_count,
OP *insert)
"optimize_optree"
This function applies some optimisations to the optree in top-down
order. It is called before the peephole optimizer, which processes
ops in execution order. Note that finalize_optree() also does a top-
down scan, but is called *after* the peephole optimizer.
void optimize_optree(OP *o)
"OP_TYPE_IS"
Returns true if the given OP is not a "NULL" pointer and if it is of
the given type.
The negation of this macro, "OP_TYPE_ISNT" is also available as well
as "OP_TYPE_IS_NN" and "OP_TYPE_ISNT_NN" which elide the NULL
pointer check.
bool OP_TYPE_IS(OP *o, Optype type)
"OP_TYPE_IS_OR_WAS"
Returns true if the given OP is not a NULL pointer and if it is of
the given type or used to be before being replaced by an OP of type
OP_NULL.
The negation of this macro, "OP_TYPE_ISNT_AND_WASNT" is also
available as well as "OP_TYPE_IS_OR_WAS_NN" and
"OP_TYPE_ISNT_AND_WASNT_NN" which elide the "NULL" pointer check.
bool OP_TYPE_IS_OR_WAS(OP *o, Optype type)
"op_wrap_finally"
NOTE: "op_wrap_finally" is experimental and may change or be removed
without notice.
Wraps the given "block" optree fragment in its own scoped block,
arranging for the "finally" optree fragment to be invoked when
leaving that block for any reason. Both optree fragments are
consumed and the combined result is returned.
OP * op_wrap_finally(OP *block, OP *finally)
"peep_t"
Described in perlguts.
"Perl_cpeep_t"
Described in perlguts.
"PL_opfreehook"
When non-"NULL", the function pointed by this variable will be
called each time an OP is freed with the corresponding OP as the
argument. This allows extensions to free any extra attribute they
have locally attached to an OP. It is also assured to first fire
for the parent OP and then for its kids.
When you replace this variable, it is considered a good practice to
store the possibly previously installed hook and that you recall it
inside your own.
On threaded perls, each thread has an independent copy of this
variable; each initialized at creation time with the current value
of the creating thread's copy.
Perl_ophook_t PL_opfreehook
"PL_peepp"
Pointer to the per-subroutine peephole optimiser. This is a
function that gets called at the end of compilation of a Perl
subroutine (or equivalently independent piece of Perl code) to
perform fixups of some ops and to perform small-scale optimisations.
The function is called once for each subroutine that is compiled,
and is passed, as sole parameter, a pointer to the op that is the
entry point to the subroutine. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather,
add code to it by wrapping the existing optimiser. The basic way to
do this can be seen in "Compile pass 3: peephole optimization" in
perlguts. If the new code wishes to operate on ops throughout the
subroutine's structure, rather than just at the top level, it is
likely to be more convenient to wrap the "PL_rpeepp" hook.
On threaded perls, each thread has an independent copy of this
variable; each initialized at creation time with the current value
of the creating thread's copy.
peep_t PL_peepp
"PL_rpeepp"
Pointer to the recursive peephole optimiser. This is a function
that gets called at the end of compilation of a Perl subroutine (or
equivalently independent piece of Perl code) to perform fixups of
some ops and to perform small-scale optimisations. The function is
called once for each chain of ops linked through their "op_next"
fields; it is recursively called to handle each side chain. It is
passed, as sole parameter, a pointer to the op that is at the head
of the chain. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather,
add code to it by wrapping the existing optimiser. The basic way to
do this can be seen in "Compile pass 3: peephole optimization" in
perlguts. If the new code wishes to operate only on ops at a
subroutine's top level, rather than throughout the structure, it is
likely to be more convenient to wrap the "PL_peepp" hook.
On threaded perls, each thread has an independent copy of this
variable; each initialized at creation time with the current value
of the creating thread's copy.
peep_t PL_rpeepp
"PMOP"
Described in perlguts.
"rv2cv_op_cv"
Examines an op, which is expected to identify a subroutine at
runtime, and attempts to determine at compile time which subroutine
it identifies. This is normally used during Perl compilation to
determine whether a prototype can be applied to a function call.
"cvop" is the op being considered, normally an "rv2cv" op. A
pointer to the identified subroutine is returned, if it could be
determined statically, and a null pointer is returned if it was not
possible to determine statically.
Currently, the subroutine can be identified statically if the RV
that the "rv2cv" is to operate on is provided by a suitable "gv" or
"const" op. A "gv" op is suitable if the GV's CV slot is populated.
A "const" op is suitable if the constant value must be an RV
pointing to a CV. Details of this process may change in future
versions of Perl. If the "rv2cv" op has the "OPpENTERSUB_AMPER"
flag set then no attempt is made to identify the subroutine
statically: this flag is used to suppress compile-time magic on a
subroutine call, forcing it to use default runtime behaviour.
If "flags" has the bit "RV2CVOPCV_MARK_EARLY" set, then the handling
of a GV reference is modified. If a GV was examined and its CV slot
was found to be empty, then the "gv" op has the "OPpEARLY_CV" flag
set. If the op is not optimised away, and the CV slot is later
populated with a subroutine having a prototype, that flag eventually
triggers the warning "called too early to check prototype".
If "flags" has the bit "RV2CVOPCV_RETURN_NAME_GV" set, then instead
of returning a pointer to the subroutine it returns a pointer to the
GV giving the most appropriate name for the subroutine in this
context. Normally this is just the "CvGV" of the subroutine, but
for an anonymous ("CvANON") subroutine that is referenced through a
GV it will be the referencing GV. The resulting "GV*" is cast to
"CV*" to be returned. A null pointer is returned as usual if there
is no statically-determinable subroutine.
CV * rv2cv_op_cv(OP *cvop, U32 flags)
"UNOP"
Described in perlguts.
"XOP"
Described in perlguts.
Pack and Unpack
"packlist"
The engine implementing pack() Perl function.
void packlist(SV *cat, const char *pat, const char *patend,
SV **beglist, SV **endlist)
"unpackstring"
The engine implementing the unpack() Perl function.
Using the template "pat..patend", this function unpacks the string
"s..strend" into a number of mortal SVs, which it pushes onto the
perl argument (@_) stack (so you will need to issue a "PUTBACK"
before and "SPAGAIN" after the call to this function). It returns
the number of pushed elements.
The "strend" and "patend" pointers should point to the byte
following the last character of each string.
Although this function returns its values on the perl argument
stack, it doesn't take any parameters from that stack (and thus in
particular there's no need to do a "PUSHMARK" before calling it,
unlike "call_pv" for example).
SSize_t unpackstring(const char *pat, const char *patend,
const char *s, const char *strend,
U32 flags)
Pad Data Structures
"CvPADLIST"
NOTE: "CvPADLIST" is experimental and may change or be removed
without notice.
CV's can have CvPADLIST(cv) set to point to a PADLIST. This is the
CV's scratchpad, which stores lexical variables and opcode temporary
and per-thread values.
For these purposes "formats" are a kind-of CV; eval""s are too
(except they're not callable at will and are always thrown away
after the eval"" is done executing). Require'd files are simply
evals without any outer lexical scope.
XSUBs do not have a "CvPADLIST". "dXSTARG" fetches values from
"PL_curpad", but that is really the callers pad (a slot of which is
allocated by every entersub). Do not get or set "CvPADLIST" if a CV
is an XSUB (as determined by CvISXSUB()), "CvPADLIST" slot is reused
for a different internal purpose in XSUBs.
The PADLIST has a C array where pads are stored.
The 0th entry of the PADLIST is a PADNAMELIST which represents the
"names" or rather the "static type information" for lexicals. The
individual elements of a PADNAMELIST are PADNAMEs. Future
refactorings might stop the PADNAMELIST from being stored in the
PADLIST's array, so don't rely on it. See "PadlistNAMES".
The CvDEPTH'th entry of a PADLIST is a PAD (an AV) which is the
stack frame at that depth of recursion into the CV. The 0th slot of
a frame AV is an AV which is @_. Other entries are storage for
variables and op targets.
Iterating over the PADNAMELIST iterates over all possible pad items.
Pad slots for targets ("SVs_PADTMP") and GVs end up having
&PL_padname_undef "names", while slots for constants have
&PL_padname_const "names" (see "pad_alloc"). That &PL_padname_undef
and &PL_padname_const are used is an implementation detail subject
to change. To test for them, use "!PadnamePV(name)" and
"PadnamePV(name) && !PadnameLEN(name)", respectively.
Only "my"/"our" variable slots get valid names. The rest are op
targets/GVs/constants which are statically allocated or resolved at
compile time. These don't have names by which they can be looked up
from Perl code at run time through eval"" the way "my"/"our"
variables can be. Since they can't be looked up by "name" but only
by their index allocated at compile time (which is usually in
"PL_op->op_targ"), wasting a name SV for them doesn't make sense.
The pad names in the PADNAMELIST have their PV holding the name of
the variable. The "COP_SEQ_RANGE_LOW" and "_HIGH" fields form a
range (low+1..high inclusive) of cop_seq numbers for which the name
is valid. During compilation, these fields may hold the special
value PERL_PADSEQ_INTRO to indicate various stages:
COP_SEQ_RANGE_LOW _HIGH
----------------- -----
PERL_PADSEQ_INTRO 0 variable not yet introduced:
{ my ($x
valid-seq# PERL_PADSEQ_INTRO variable in scope:
{ my ($x);
valid-seq# valid-seq# compilation of scope complete:
{ my ($x); .... }
When a lexical var hasn't yet been introduced, it already exists
from the perspective of duplicate declarations, but not for variable
lookups, e.g.
my ($x, $x); # '"my" variable $x masks earlier declaration'
my $x = $x; # equal to my $x = $::x;
For typed lexicals "PadnameTYPE" points at the type stash. For
"our" lexicals, "PadnameOURSTASH" points at the stash of the
associated global (so that duplicate "our" declarations in the same
package can be detected). "PadnameGEN" is sometimes used to store
the generation number during compilation.
If "PadnameOUTER" is set on the pad name, then that slot in the
frame AV is a REFCNT'ed reference to a lexical from "outside". Such
entries are sometimes referred to as 'fake'. In this case, the name
does not use 'low' and 'high' to store a cop_seq range, since it is
in scope throughout. Instead 'high' stores some flags containing
info about the real lexical (is it declared in an anon, and is it
capable of being instantiated multiple times?), and for fake ANONs,
'low' contains the index within the parent's pad where the lexical's
value is stored, to make cloning quicker.
If the 'name' is "&" the corresponding entry in the PAD is a CV
representing a possible closure.
Note that formats are treated as anon subs, and are cloned each time
write is called (if necessary).
The flag "SVs_PADSTALE" is cleared on lexicals each time the my() is
executed, and set on scope exit. This allows the "Variable $x is
not available" warning to be generated in evals, such as
{ my $x = 1; sub f { eval '$x'} } f();
For state vars, "SVs_PADSTALE" is overloaded to mean 'not yet
initialised', but this internal state is stored in a separate pad
entry.
PADLIST * CvPADLIST(CV *cv)
"pad_add_name_pvs"
Exactly like "pad_add_name_pvn", but takes a literal string instead
of a string/length pair.
PADOFFSET pad_add_name_pvs("name", U32 flags, HV *typestash,
HV *ourstash)
"PadARRAY"
NOTE: "PadARRAY" is experimental and may change or be removed
without notice.
The C array of pad entries.
SV ** PadARRAY(PAD * pad)
"pad_findmy_pvs"
Exactly like "pad_findmy_pvn", but takes a literal string instead of
a string/length pair.
PADOFFSET pad_findmy_pvs("name", U32 flags)
"PadlistARRAY"
NOTE: "PadlistARRAY" is experimental and may change or be removed
without notice.
The C array of a padlist, containing the pads. Only subscript it
with numbers >= 1, as the 0th entry is not guaranteed to remain
usable.
PAD ** PadlistARRAY(PADLIST * padlist)
"PadlistMAX"
NOTE: "PadlistMAX" is experimental and may change or be removed
without notice.
The index of the last allocated space in the padlist. Note that the
last pad may be in an earlier slot. Any entries following it will
be "NULL" in that case.
SSize_t PadlistMAX(PADLIST * padlist)
"PadlistNAMES"
NOTE: "PadlistNAMES" is experimental and may change or be removed
without notice.
The names associated with pad entries.
PADNAMELIST * PadlistNAMES(PADLIST * padlist)
"PadlistNAMESARRAY"
NOTE: "PadlistNAMESARRAY" is experimental and may change or be
removed without notice.
The C array of pad names.
PADNAME ** PadlistNAMESARRAY(PADLIST * padlist)
"PadlistNAMESMAX"
NOTE: "PadlistNAMESMAX" is experimental and may change or be removed
without notice.
The index of the last pad name.
SSize_t PadlistNAMESMAX(PADLIST * padlist)
"PadlistREFCNT"
NOTE: "PadlistREFCNT" is experimental and may change or be removed
without notice.
The reference count of the padlist. Currently this is always 1.
U32 PadlistREFCNT(PADLIST * padlist)
"PadMAX"
NOTE: "PadMAX" is experimental and may change or be removed without
notice.
The index of the last pad entry.
SSize_t PadMAX(PAD * pad)
"PadnameLEN"
NOTE: "PadnameLEN" is experimental and may change or be removed
without notice.
The length of the name.
STRLEN PadnameLEN(PADNAME * pn)
"PadnamelistARRAY"
NOTE: "PadnamelistARRAY" is experimental and may change or be
removed without notice.
The C array of pad names.
PADNAME ** PadnamelistARRAY(PADNAMELIST * pnl)
"PadnamelistMAX"
NOTE: "PadnamelistMAX" is experimental and may change or be removed
without notice.
The index of the last pad name.
SSize_t PadnamelistMAX(PADNAMELIST * pnl)
"PadnamelistREFCNT"
NOTE: "PadnamelistREFCNT" is experimental and may change or be
removed without notice.
The reference count of the pad name list.
SSize_t PadnamelistREFCNT(PADNAMELIST * pnl)
"PadnamelistREFCNT_dec"
NOTE: "PadnamelistREFCNT_dec" is experimental and may change or be
removed without notice.
Lowers the reference count of the pad name list.
void PadnamelistREFCNT_dec(PADNAMELIST * pnl)
"PadnamePV"
NOTE: "PadnamePV" is experimental and may change or be removed
without notice.
The name stored in the pad name struct. This returns "NULL" for a
target slot.
char * PadnamePV(PADNAME * pn)
"PadnameREFCNT"
NOTE: "PadnameREFCNT" is experimental and may change or be removed
without notice.
The reference count of the pad name.
SSize_t PadnameREFCNT(PADNAME * pn)
"PadnameREFCNT_dec"
NOTE: "PadnameREFCNT_dec" is experimental and may change or be
removed without notice.
Lowers the reference count of the pad name.
void PadnameREFCNT_dec(PADNAME * pn)
"PadnameREFCNT_inc"
NOTE: "PadnameREFCNT_inc" is experimental and may change or be
removed without notice.
Increases the reference count of the pad name. Returns the pad name
itself.
PADNAME * PadnameREFCNT_inc(PADNAME * pn)
"PadnameSV"
NOTE: "PadnameSV" is experimental and may change or be removed
without notice.
Returns the pad name as a mortal SV.
SV * PadnameSV(PADNAME * pn)
"PadnameUTF8"
NOTE: "PadnameUTF8" is experimental and may change or be removed
without notice.
Whether PadnamePV is in UTF-8. Currently, this is always true.
bool PadnameUTF8(PADNAME * pn)
"pad_new"
Create a new padlist, updating the global variables for the
currently-compiling padlist to point to the new padlist. The
following flags can be OR'ed together:
padnew_CLONE this pad is for a cloned CV
padnew_SAVE save old globals on the save stack
padnew_SAVESUB also save extra stuff for start of sub
PADLIST * pad_new(int flags)
"PL_comppad"
NOTE: "PL_comppad" is experimental and may change or be removed
without notice.
During compilation, this points to the array containing the values
part of the pad for the currently-compiling code. (At runtime a CV
may have many such value arrays; at compile time just one is
constructed.) At runtime, this points to the array containing the
currently-relevant values for the pad for the currently-executing
code.
"PL_comppad_name"
NOTE: "PL_comppad_name" is experimental and may change or be removed
without notice.
During compilation, this points to the array containing the names
part of the pad for the currently-compiling code.
"PL_curpad"
NOTE: "PL_curpad" is experimental and may change or be removed
without notice.
Points directly to the body of the "PL_comppad" array. (I.e., this
is PadARRAY(PL_comppad).)
"SVs_PADMY"
"DEPRECATED!" It is planned to remove "SVs_PADMY" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Described in perlguts.
"SVs_PADTMP"
Described in perlguts.
Password and Group access
"GRPASSWD"
This symbol, if defined, indicates to the C program that "struct
group" in grp.h contains "gr_passwd".
"HAS_ENDGRENT"
This symbol, if defined, indicates that the getgrent routine is
available for finalizing sequential access of the group database.
"HAS_ENDGRENT_R"
This symbol, if defined, indicates that the "endgrent_r" routine is
available to endgrent re-entrantly.
"HAS_ENDPWENT"
This symbol, if defined, indicates that the "endpwent" routine is
available for finalizing sequential access of the passwd database.
"HAS_ENDPWENT_R"
This symbol, if defined, indicates that the "endpwent_r" routine is
available to endpwent re-entrantly.
"HAS_GETGRENT"
This symbol, if defined, indicates that the "getgrent" routine is
available for sequential access of the group database.
"HAS_GETGRENT_R"
This symbol, if defined, indicates that the "getgrent_r" routine is
available to getgrent re-entrantly.
"HAS_GETPWENT"
This symbol, if defined, indicates that the "getpwent" routine is
available for sequential access of the passwd database. If this is
not available, the older getpw() function may be available.
"HAS_GETPWENT_R"
This symbol, if defined, indicates that the "getpwent_r" routine is
available to getpwent re-entrantly.
"HAS_SETGRENT"
This symbol, if defined, indicates that the "setgrent" routine is
available for initializing sequential access of the group database.
"HAS_SETGRENT_R"
This symbol, if defined, indicates that the "setgrent_r" routine is
available to setgrent re-entrantly.
"HAS_SETPWENT"
This symbol, if defined, indicates that the "setpwent" routine is
available for initializing sequential access of the passwd database.
"HAS_SETPWENT_R"
This symbol, if defined, indicates that the "setpwent_r" routine is
available to setpwent re-entrantly.
"PWAGE"
This symbol, if defined, indicates to the C program that "struct
passwd" contains "pw_age".
"PWCHANGE"
This symbol, if defined, indicates to the C program that "struct
passwd" contains "pw_change".
"PWCLASS"
This symbol, if defined, indicates to the C program that "struct
passwd" contains "pw_class".
"PWCOMMENT"
This symbol, if defined, indicates to the C program that "struct
passwd" contains "pw_comment".
"PWEXPIRE"
This symbol, if defined, indicates to the C program that "struct
passwd" contains "pw_expire".
"PWGECOS"
This symbol, if defined, indicates to the C program that "struct
passwd" contains "pw_gecos".
"PWPASSWD"
This symbol, if defined, indicates to the C program that "struct
passwd" contains "pw_passwd".
"PWQUOTA"
This symbol, if defined, indicates to the C program that "struct
passwd" contains "pw_quota".
Paths to system commands
"CSH"
This symbol, if defined, contains the full pathname of csh.
"LOC_SED"
This symbol holds the complete pathname to the sed program.
"SH_PATH"
This symbol contains the full pathname to the shell used on this on
this system to execute Bourne shell scripts. Usually, this will be
/bin/sh, though it's possible that some systems will have /bin/ksh,
/bin/pdksh, /bin/ash, /bin/bash, or even something such as
D:/bin/sh.exe.
Prototype information
"CRYPT_R_PROTO"
This symbol encodes the prototype of "crypt_r". It is zero if
"d_crypt_r" is undef, and one of the "REENTRANT_PROTO_T_ABC" macros
of reentr.h if "d_crypt_r" is defined.
"CTERMID_R_PROTO"
This symbol encodes the prototype of "ctermid_r". It is zero if
"d_ctermid_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_ctermid_r" is defined.
"DRAND48_R_PROTO"
This symbol encodes the prototype of "drand48_r". It is zero if
"d_drand48_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_drand48_r" is defined.
"ENDGRENT_R_PROTO"
This symbol encodes the prototype of "endgrent_r". It is zero if
"d_endgrent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_endgrent_r" is defined.
"ENDHOSTENT_R_PROTO"
This symbol encodes the prototype of "endhostent_r". It is zero if
"d_endhostent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_endhostent_r" is defined.
"ENDNETENT_R_PROTO"
This symbol encodes the prototype of "endnetent_r". It is zero if
"d_endnetent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_endnetent_r" is defined.
"ENDPROTOENT_R_PROTO"
This symbol encodes the prototype of "endprotoent_r". It is zero if
"d_endprotoent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_endprotoent_r" is defined.
"ENDPWENT_R_PROTO"
This symbol encodes the prototype of "endpwent_r". It is zero if
"d_endpwent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_endpwent_r" is defined.
"ENDSERVENT_R_PROTO"
This symbol encodes the prototype of "endservent_r". It is zero if
"d_endservent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_endservent_r" is defined.
"GDBMNDBM_H_USES_PROTOTYPES"
This symbol, if defined, indicates that gdbm/ndbm.h uses real "ANSI"
C prototypes instead of K&R style function declarations without any
parameter information. While "ANSI" C prototypes are supported in
C++, K&R style function declarations will yield errors.
"GDBM_NDBM_H_USES_PROTOTYPES"
This symbol, if defined, indicates that <gdbm-ndbm.h> uses real
"ANSI" C prototypes instead of K&R style function declarations
without any parameter information. While "ANSI" C prototypes are
supported in C++, K&R style function declarations will yield errors.
"GETGRENT_R_PROTO"
This symbol encodes the prototype of "getgrent_r". It is zero if
"d_getgrent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getgrent_r" is defined.
"GETGRGID_R_PROTO"
This symbol encodes the prototype of "getgrgid_r". It is zero if
"d_getgrgid_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getgrgid_r" is defined.
"GETGRNAM_R_PROTO"
This symbol encodes the prototype of "getgrnam_r". It is zero if
"d_getgrnam_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getgrnam_r" is defined.
"GETHOSTBYADDR_R_PROTO"
This symbol encodes the prototype of "gethostbyaddr_r". It is zero
if "d_gethostbyaddr_r" is undef, and one of the
"REENTRANT_PROTO_T_ABC" macros of reentr.h if "d_gethostbyaddr_r" is
defined.
"GETHOSTBYNAME_R_PROTO"
This symbol encodes the prototype of "gethostbyname_r". It is zero
if "d_gethostbyname_r" is undef, and one of the
"REENTRANT_PROTO_T_ABC" macros of reentr.h if "d_gethostbyname_r" is
defined.
"GETHOSTENT_R_PROTO"
This symbol encodes the prototype of "gethostent_r". It is zero if
"d_gethostent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_gethostent_r" is defined.
"GETLOGIN_R_PROTO"
This symbol encodes the prototype of "getlogin_r". It is zero if
"d_getlogin_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getlogin_r" is defined.
"GETNETBYADDR_R_PROTO"
This symbol encodes the prototype of "getnetbyaddr_r". It is zero
if "d_getnetbyaddr_r" is undef, and one of the
"REENTRANT_PROTO_T_ABC" macros of reentr.h if "d_getnetbyaddr_r" is
defined.
"GETNETBYNAME_R_PROTO"
This symbol encodes the prototype of "getnetbyname_r". It is zero
if "d_getnetbyname_r" is undef, and one of the
"REENTRANT_PROTO_T_ABC" macros of reentr.h if "d_getnetbyname_r" is
defined.
"GETNETENT_R_PROTO"
This symbol encodes the prototype of "getnetent_r". It is zero if
"d_getnetent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getnetent_r" is defined.
"GETPROTOBYNAME_R_PROTO"
This symbol encodes the prototype of "getprotobyname_r". It is zero
if "d_getprotobyname_r" is undef, and one of the
"REENTRANT_PROTO_T_ABC" macros of reentr.h if "d_getprotobyname_r"
is defined.
"GETPROTOBYNUMBER_R_PROTO"
This symbol encodes the prototype of "getprotobynumber_r". It is
zero if "d_getprotobynumber_r" is undef, and one of the
"REENTRANT_PROTO_T_ABC" macros of reentr.h if "d_getprotobynumber_r"
is defined.
"GETPROTOENT_R_PROTO"
This symbol encodes the prototype of "getprotoent_r". It is zero if
"d_getprotoent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getprotoent_r" is defined.
"GETPWENT_R_PROTO"
This symbol encodes the prototype of "getpwent_r". It is zero if
"d_getpwent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getpwent_r" is defined.
"GETPWNAM_R_PROTO"
This symbol encodes the prototype of "getpwnam_r". It is zero if
"d_getpwnam_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getpwnam_r" is defined.
"GETPWUID_R_PROTO"
This symbol encodes the prototype of "getpwuid_r". It is zero if
"d_getpwuid_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getpwuid_r" is defined.
"GETSERVBYNAME_R_PROTO"
This symbol encodes the prototype of "getservbyname_r". It is zero
if "d_getservbyname_r" is undef, and one of the
"REENTRANT_PROTO_T_ABC" macros of reentr.h if "d_getservbyname_r" is
defined.
"GETSERVBYPORT_R_PROTO"
This symbol encodes the prototype of "getservbyport_r". It is zero
if "d_getservbyport_r" is undef, and one of the
"REENTRANT_PROTO_T_ABC" macros of reentr.h if "d_getservbyport_r" is
defined.
"GETSERVENT_R_PROTO"
This symbol encodes the prototype of "getservent_r". It is zero if
"d_getservent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getservent_r" is defined.
"GETSPNAM_R_PROTO"
This symbol encodes the prototype of "getspnam_r". It is zero if
"d_getspnam_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_getspnam_r" is defined.
"HAS_DBMINIT_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the dbminit() function. Otherwise, it is up to the
program to supply one. A good guess is
extern int dbminit(char *);
"HAS_DRAND48_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the drand48() function. Otherwise, it is up to the
program to supply one. A good guess is
extern double drand48(void);
"HAS_FLOCK_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the flock() function. Otherwise, it is up to the
program to supply one. A good guess is
extern int flock(int, int);
"HAS_GETHOST_PROTOS"
This symbol, if defined, indicates that netdb.h includes prototypes
for gethostent(), gethostbyname(), and gethostbyaddr(). Otherwise,
it is up to the program to guess them. See netdbtype.U (part of
metaconfig) for probing for various "Netdb_xxx_t" types.
"HAS_GETNET_PROTOS"
This symbol, if defined, indicates that netdb.h includes prototypes
for getnetent(), getnetbyname(), and getnetbyaddr(). Otherwise, it
is up to the program to guess them. See netdbtype.U (part of
metaconfig) for probing for various "Netdb_xxx_t" types.
"HAS_GETPROTO_PROTOS"
This symbol, if defined, indicates that netdb.h includes prototypes
for getprotoent(), getprotobyname(), and getprotobyaddr().
Otherwise, it is up to the program to guess them. See netdbtype.U
(part of metaconfig) for probing for various "Netdb_xxx_t" types.
"HAS_GETSERV_PROTOS"
This symbol, if defined, indicates that netdb.h includes prototypes
for getservent(), getservbyname(), and getservbyaddr(). Otherwise,
it is up to the program to guess them. See netdbtype.U (part of
metaconfig) for probing for various "Netdb_xxx_t" types.
"HAS_MODFL_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the modfl() function. Otherwise, it is up to the
program to supply one.
"HAS_SBRK_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the sbrk() function. Otherwise, it is up to the
program to supply one. Good guesses are
extern void* sbrk(int);
extern void* sbrk(size_t);
"HAS_SETRESGID_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the setresgid() function. Otherwise, it is up to the
program to supply one. Good guesses are
extern int setresgid(uid_t ruid, uid_t euid, uid_t suid);
"HAS_SETRESUID_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the setresuid() function. Otherwise, it is up to the
program to supply one. Good guesses are
extern int setresuid(uid_t ruid, uid_t euid, uid_t suid);
"HAS_SHMAT_PROTOTYPE"
This symbol, if defined, indicates that the sys/shm.h includes a
prototype for shmat(). Otherwise, it is up to the program to guess
one. "Shmat_t" "shmat(int, Shmat_t, int)" is a good guess, but not
always right so it should be emitted by the program only when
"HAS_SHMAT_PROTOTYPE" is not defined to avoid conflicting defs.
"HAS_SOCKATMARK_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the sockatmark() function. Otherwise, it is up to the
program to supply one. A good guess is
extern int sockatmark(int);
"HAS_SYSCALL_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the syscall() function. Otherwise, it is up to the
program to supply one. Good guesses are
extern int syscall(int, ...);
extern int syscall(long, ...);
"HAS_TELLDIR_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the telldir() function. Otherwise, it is up to the
program to supply one. A good guess is
extern long telldir(DIR*);
"NDBM_H_USES_PROTOTYPES"
This symbol, if defined, indicates that ndbm.h uses real "ANSI" C
prototypes instead of K&R style function declarations without any
parameter information. While "ANSI" C prototypes are supported in
C++, K&R style function declarations will yield errors.
"RANDOM_R_PROTO"
This symbol encodes the prototype of "random_r". It is zero if
"d_random_r" is undef, and one of the "REENTRANT_PROTO_T_ABC" macros
of reentr.h if "d_random_r" is defined.
"READDIR_R_PROTO"
This symbol encodes the prototype of "readdir_r". It is zero if
"d_readdir_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_readdir_r" is defined.
"SETGRENT_R_PROTO"
This symbol encodes the prototype of "setgrent_r". It is zero if
"d_setgrent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_setgrent_r" is defined.
"SETHOSTENT_R_PROTO"
This symbol encodes the prototype of "sethostent_r". It is zero if
"d_sethostent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_sethostent_r" is defined.
"SETLOCALE_R_PROTO"
This symbol encodes the prototype of "setlocale_r". It is zero if
"d_setlocale_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_setlocale_r" is defined.
"SETNETENT_R_PROTO"
This symbol encodes the prototype of "setnetent_r". It is zero if
"d_setnetent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_setnetent_r" is defined.
"SETPROTOENT_R_PROTO"
This symbol encodes the prototype of "setprotoent_r". It is zero if
"d_setprotoent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_setprotoent_r" is defined.
"SETPWENT_R_PROTO"
This symbol encodes the prototype of "setpwent_r". It is zero if
"d_setpwent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_setpwent_r" is defined.
"SETSERVENT_R_PROTO"
This symbol encodes the prototype of "setservent_r". It is zero if
"d_setservent_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_setservent_r" is defined.
"SRANDOM_R_PROTO"
This symbol encodes the prototype of "srandom_r". It is zero if
"d_srandom_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_srandom_r" is defined.
"SRAND48_R_PROTO"
This symbol encodes the prototype of "srand48_r". It is zero if
"d_srand48_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_srand48_r" is defined.
"STRERROR_R_PROTO"
This symbol encodes the prototype of "strerror_r". It is zero if
"d_strerror_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_strerror_r" is defined.
"TMPNAM_R_PROTO"
This symbol encodes the prototype of "tmpnam_r". It is zero if
"d_tmpnam_r" is undef, and one of the "REENTRANT_PROTO_T_ABC" macros
of reentr.h if "d_tmpnam_r" is defined.
"TTYNAME_R_PROTO"
This symbol encodes the prototype of "ttyname_r". It is zero if
"d_ttyname_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_ttyname_r" is defined.
Reference-counted stack manipulation
Functions for pushing and pulling items on the stack when the stack is
reference counted. They are intended as replacements for the old PUSHs,
POPi, EXTEND etc pp macros within pp functions.
"rpp_context"
NOTE: "rpp_context" is experimental and may change or be removed
without notice.
Impose void, scalar or list context on the stack. First, pop
"extra" items off the stack, then when "gimme" is: "G_LIST":
return as-is. "G_VOID": pop everything back to "mark" "G_SCALAR":
move the top stack item (or &PL_sv_undef if none) to "mark+1" and
free everything above it.
void rpp_context(SV **mark, U8 gimme, SSize_t extra)
"rpp_extend"
NOTE: "rpp_extend" is experimental and may change or be removed
without notice.
Ensures that there is space on the stack to push "n" items,
extending it if necessary.
void rpp_extend(SSize_t n)
"rpp_invoke_xs"
NOTE: "rpp_invoke_xs" is experimental and may change or be removed
without notice.
Call the XS function associated with "cv". Wraps the call if
necessary to handle XS functions which are not aware of reference-
counted stacks.
void rpp_invoke_xs(CV *cv)
"rpp_is_lone"
NOTE: "rpp_is_lone" is experimental and may change or be removed
without notice.
Indicates whether the stacked SV "sv" (assumed to be not yet popped
off the stack) is only kept alive due to a single reference from the
argument stack and/or and the temps stack.
This can used for example to decide whether the copying of return
values in rvalue context can be skipped, or whether it shouldn't be
assigned to in lvalue context.
bool rpp_is_lone(SV *sv)
"rpp_popfree_1_NN"
NOTE: "rpp_popfree_1_NN" is experimental and may change or be
removed without notice.
A variant of rpp_popfree_1() which assumes that the pointer being
popped off the stack is non-NULL.
void rpp_popfree_1_NN()
"rpp_popfree_2_NN"
NOTE: "rpp_popfree_2_NN" is experimental and may change or be
removed without notice.
A variant of rpp_popfree_2() which assumes that the two pointers
being popped off the stack are non-NULL.
void rpp_popfree_2_NN()
"rpp_popfree_to"
NOTE: "rpp_popfree_to" is experimental and may change or be removed
without notice.
Pop and free all items on the argument stack above "sp". On return,
"PL_stack_sp" will be equal to "sp".
void rpp_popfree_to(SV **sp)
"rpp_popfree_to_NN"
NOTE: "rpp_popfree_to_NN" is experimental and may change or be
removed without notice.
A variant of rpp_popfree_to() which assumes that all the pointers
being popped off the stack are non-NULL.
void rpp_popfree_to_NN(SV **sp)
"rpp_popfree_1"
NOTE: "rpp_popfree_1" is experimental and may change or be removed
without notice.
Pop and free the top item on the argument stack and update
"PL_stack_sp".
void rpp_popfree_1()
"rpp_popfree_2"
NOTE: "rpp_popfree_2" is experimental and may change or be removed
without notice.
Pop and free the top two items on the argument stack and update
"PL_stack_sp".
void rpp_popfree_2()
"rpp_pop_1_norc"
NOTE: "rpp_pop_1_norc" is experimental and may change or be removed
without notice.
Pop and return the top item off the argument stack and update
"PL_stack_sp". It's similar to rpp_popfree_1(), except that it
actually returns a value, and it doesn't decrement the SV's
reference count. On non-"PERL_RC_STACK" builds it actually
increments the SV's reference count.
This is useful in cases where the popped value is immediately
embedded somewhere e.g. via av_store(), allowing you skip
decrementing and then immediately incrementing the reference count
again (and risk prematurely freeing the SV if it had a RC of 1). On
non-RC builds, the reference count bookkeeping still works too,
which is why it should be used rather than a simple
"*PL_stack_sp--".
SV * rpp_pop_1_norc()
"rpp_push_1_norc"
NOTE: "rpp_push_1_norc" is experimental and may change or be removed
without notice.
Push "sv" onto the stack without incrementing its reference count,
and update "PL_stack_sp". On non-PERL_RC_STACK builds, mortalise
too.
This is most useful where an SV has just been created and already
has a reference count of 1, but has not yet been anchored anywhere.
void rpp_push_1_norc(SV *sv)
"rpp_push_1"
"rpp_push_IMM"
"rpp_push_2"
"rpp_xpush_1"
"rpp_xpush_IMM"
"rpp_xpush_2"
NOTE: all these forms are experimental and may change or be removed
without notice.
Push one or two SVs onto the stack, incrementing their reference
counts and updating "PL_stack_sp". With the "x" variants, it extends
the stack first. The "IMM" variants assume that the single argument
is an immortal such as <&PL_sv_undef> and, for efficiency, will skip
incrementing its reference count.
void rpp_push_1 (SV *sv)
void rpp_push_IMM (SV *sv)
void rpp_push_2 (SV *sv1, SV *sv2)
void rpp_xpush_1 (SV *sv)
void rpp_xpush_IMM(SV *sv)
void rpp_xpush_2 (SV *sv1, SV *sv2)
"rpp_replace_at"
NOTE: "rpp_replace_at" is experimental and may change or be removed
without notice.
Replace the SV at address sp within the stack with "sv", while
suitably adjusting reference counts. Equivalent to "*sp = sv",
except with proper reference count handling.
void rpp_replace_at(SV **sp, SV *sv)
"rpp_replace_at_NN"
NOTE: "rpp_replace_at_NN" is experimental and may change or be
removed without notice.
A variant of rpp_replace_at() which assumes that the SV pointer on
the stack is non-NULL.
void rpp_replace_at_NN(SV **sp, SV *sv)
"rpp_replace_at_norc"
NOTE: "rpp_replace_at_norc" is experimental and may change or be
removed without notice.
Replace the SV at address sp within the stack with "sv", while
suitably adjusting the reference count of the old SV. Equivalent to
"*sp = sv", except with proper reference count handling.
"sv"'s reference count doesn't get incremented. On
non-"PERL_RC_STACK" builds, it gets mortalised too.
This is most useful where an SV has just been created and already
has a reference count of 1, but has not yet been anchored anywhere.
void rpp_replace_at_norc(SV **sp, SV *sv)
"rpp_replace_at_norc_NN"
NOTE: "rpp_replace_at_norc_NN" is experimental and may change or be
removed without notice.
A variant of rpp_replace_at_norc() which assumes that the SV pointer
on the stack is non-NULL.
void rpp_replace_at_norc_NN(SV **sp, SV *sv)
"rpp_replace_1_1"
"rpp_replace_1_1_NN"
"rpp_replace_1_IMM_NN"
NOTE: all these forms are experimental and may change or be removed
without notice.
Replace the current top stack item with "sv", while suitably
adjusting reference counts. Equivalent to rpp_popfree_1();
rpp_push_1(sv), but is more efficient and handles both SVs being the
same.
The "_NN" variant assumes that the pointer on the stack to the SV
being freed is non-NULL.
The "IMM_NN" variant is like the "_NN" variant, but in addition,
assumes that the single argument is an immortal such as
<&PL_sv_undef> and, for efficiency, will skip incrementing its
reference count.
void rpp_replace_1_1(SV *sv)
"rpp_replace_2_1"
"rpp_replace_2_1_NN"
"rpp_replace_2_IMM_NN"
NOTE: all these forms are experimental and may change or be removed
without notice.
Replace the current top to stacks item with "sv", while suitably
adjusting reference counts. Equivalent to rpp_popfree_2();
rpp_push_1(sv), but is more efficient and handles SVs being the
same.
The "_NN" variant assumes that the pointers on the stack to the SVs
being freed are non-NULL.
The "IMM_NN" variant is like the "_NN" variant, but in addition,
assumes that the single argument is an immortal such as
<&PL_sv_undef> and, for efficiency, will skip incrementing its
reference count.
void rpp_replace_2_1(SV *sv)
"rpp_stack_is_rc"
NOTE: "rpp_stack_is_rc" is experimental and may change or be removed
without notice.
Returns a boolean value indicating whether the stack is currently
reference-counted. Note that if the stack is split (bottom half RC,
top half non-RC), this function returns false, even if the top half
currently contains zero items.
bool rpp_stack_is_rc()
"rpp_try_AMAGIC_1"
"rpp_try_AMAGIC_2"
NOTE: both forms are experimental and may change or be removed
without notice.
Check whether either of the one or two SVs at the top of the stack
is magical or a ref, and in either case handle it specially: invoke
get magic, call an overload method, or replace a ref with a
temporary numeric value, as appropriate. If this function returns
true, it indicates that the correct return value is already on the
stack. Intended to be used at the beginning of the PP function for
unary or binary ops.
bool rpp_try_AMAGIC_1(int method, int flags)
"XSPP_wrapped"
NOTE: "XSPP_wrapped" is experimental and may change or be removed
without notice.
Declare and wrap a non-reference-counted PP-style function. On
traditional perl builds where the stack isn't reference-counted,
this just produces a function declaration like
OP * xsppw_name(pTHX)
Conversely, in ref-counted builds it creates xsppw_name() as a small
wrapper function which calls the real function via a wrapper which
processes the args and return values to ensure that reference counts
are properly handled for code which uses old-style dSP, PUSHs(),
POPs() etc, which don't adjust the reference counts of the items
they manipulate.
xsppw_nargs indicates how many arguments the function consumes off
the stack. It can be a constant value or an expression, such as
((PL_op->op_flags & OPf_STACKED) ? 2 : 1)
Alternatively if xsppw_nlists is 1, it indicates that the PP
function consumes a list (or - rarely - if 2, consumes two lists,
like pp_aassign()), as indicated by the top markstack position.
This is intended as a temporary fix when converting XS code to run
under PERL_RC_STACK builds. In the longer term, the PP function
should be rewritten to replace PUSHs() etc with rpp_push_1() etc.
XSPP_wrapped(xsppw_name, I32 xsppw_nargs, I32 xsppw_nlists)
REGEXP Functions
"pregcomp"
Described in perlreguts.
REGEXP * pregcomp(SV * const pattern, const U32 flags)
"pregexec"
Described in perlreguts.
I32 pregexec(REGEXP * const prog, char *stringarg, char *strend,
char *strbeg, SSize_t minend, SV *screamer,
U32 nosave)
"re_compile"
Compile the regular expression pattern "pattern", returning a
pointer to the compiled object for later matching with the internal
regex engine.
This function is typically used by a custom regexp engine ".comp()"
function to hand off to the core regexp engine those patterns it
doesn't want to handle itself (typically passing through the same
flags it was called with). In almost all other cases, a regexp
should be compiled by calling ""pregcomp"" to compile using the
currently active regexp engine.
If "pattern" is already a "REGEXP", this function does nothing but
return a pointer to the input. Otherwise the PV is extracted and
treated like a string representing a pattern. See perlre.
The possible flags for "rx_flags" are documented in perlreapi.
Their names all begin with "RXf_".
REGEXP * re_compile(SV * const pattern, U32 orig_rx_flags)
"re_dup_guts"
Duplicate a regexp.
This routine is expected to clone a given regexp structure. It is
only compiled under USE_ITHREADS.
After all of the core data stored in struct regexp is duplicated the
"regexp_engine.dupe" method is used to copy any private data stored
in the *pprivate pointer. This allows extensions to handle any
duplication they need to do.
void re_dup_guts(const REGEXP *sstr, REGEXP *dstr,
CLONE_PARAMS *param)
"REGEX_LOCALE_CHARSET"
Described in perlreapi.
"REGEXP"
Described in perlreapi.
"regexp_engine"
When a regexp is compiled, its "engine" field is then set to point
at the appropriate structure, so that when it needs to be used Perl
can find the right routines to do so.
In order to install a new regexp handler, $^H{regcomp} is set to an
integer which (when casted appropriately) resolves to one of these
structures. When compiling, the "comp" method is executed, and the
resulting "regexp" structure's engine field is expected to point
back at the same structure.
The pTHX_ symbol in the definition is a macro used by Perl under
threading to provide an extra argument to the routine holding a
pointer back to the interpreter that is executing the regexp. So
under threading all routines get an extra argument.
"regexp_paren_pair"
Described in perlreapi.
"regmatch_info"
Some basic information about the current match that is created by
Perl_regexec_flags and then passed to regtry(), regmatch() etc. It
is allocated as a local var on the stack, so nothing should be
stored in it that needs preserving or clearing up on croak(). For
that, see the aux_info and aux_info_eval members of the
regmatch_state union.
"REXEC_COPY_SKIP_POST"
"REXEC_COPY_SKIP_PRE"
"REXEC_COPY_STR"
Described in perlreapi.
"RXapif_ALL"
"RXapif_CLEAR"
"RXapif_DELETE"
"RXapif_EXISTS"
"RXapif_FETCH"
"RXapif_FIRSTKEY"
"RXapif_NEXTKEY"
"RXapif_ONE"
"RXapif_REGNAME"
"RXapif_REGNAMES"
"RXapif_REGNAMES_COUNT"
"RXapif_SCALAR"
"RXapif_STORE"
Described in perlreapi.
"RX_BUFF_IDX_CARET_FULLMATCH"
"RX_BUFF_IDX_CARET_POSTMATCH"
"RX_BUFF_IDX_CARET_PREMATCH"
"RX_BUFF_IDX_FULLMATCH"
"RX_BUFF_IDX_POSTMATCH"
"RX_BUFF_IDX_PREMATCH"
Described in perlreapi.
"RXf_NO_INPLACE_SUBST"
"RXf_NULL"
"RXf_SKIPWHITE"
"RXf_SPLIT"
"RXf_START_ONLY"
"RXf_WHITE"
Described in perlreapi.
"RXf_PMf_EXTENDED"
"RXf_PMf_FOLD"
"RXf_PMf_KEEPCOPY"
"RXf_PMf_MULTILINE"
"RXf_PMf_SINGLELINE"
Described in perlreapi.
"RX_MATCH_COPIED"
Described in perlreapi.
RX_MATCH_COPIED(const REGEXP * rx_sv)
"struct regexp"
Described in perlreapi.
"SvRX"
Convenience macro to get the REGEXP from a SV. This is
approximately equivalent to the following snippet:
if (SvMAGICAL(sv))
mg_get(sv);
if (SvROK(sv))
sv = MUTABLE_SV(SvRV(sv));
if (SvTYPE(sv) == SVt_REGEXP)
return (REGEXP*) sv;
"NULL" will be returned if a REGEXP* is not found.
REGEXP * SvRX(SV *sv)
"SvRXOK"
Returns a boolean indicating whether the SV (or the one it
references) is a REGEXP.
If you want to do something with the REGEXP* later use SvRX instead
and check for NULL.
bool SvRXOK(SV* sv)
"SV_SAVED_COPY"
Described in perlreapi.
Reports and Formats
These are used in the simple report generation feature of Perl. See
perlform.
"IoBOTTOM_GV"
Described in perlguts.
GV * IoBOTTOM_GV(IO *io)
"IoBOTTOM_NAME"
Described in perlguts.
char * IoBOTTOM_NAME(IO *io)
"IoFMT_GV"
Described in perlguts.
GV * IoFMT_GV(IO *io)
"IoFMT_NAME"
Described in perlguts.
char * IoFMT_NAME(IO *io)
"IoLINES"
Described in perlguts.
IV IoLINES(IO *io)
"IoLINES_LEFT"
Described in perlguts.
IV IoLINES_LEFT(IO *io)
"IoPAGE"
Described in perlguts.
IV IoPAGE(IO *io)
"IoPAGE_LEN"
Described in perlguts.
IV IoPAGE_LEN(IO *io)
"IoTOP_GV"
Described in perlguts.
GV * IoTOP_GV(IO *io)
"IoTOP_NAME"
Described in perlguts.
char * IoTOP_NAME(IO *io)
Signals
"HAS_SIGINFO_SI_ADDR"
This symbol, if defined, indicates that "siginfo_t" has the
"si_addr" member
"HAS_SIGINFO_SI_BAND"
This symbol, if defined, indicates that "siginfo_t" has the
"si_band" member
"HAS_SIGINFO_SI_ERRNO"
This symbol, if defined, indicates that "siginfo_t" has the
"si_errno" member
"HAS_SIGINFO_SI_PID"
This symbol, if defined, indicates that "siginfo_t" has the "si_pid"
member
"HAS_SIGINFO_SI_STATUS"
This symbol, if defined, indicates that "siginfo_t" has the
"si_status" member
"HAS_SIGINFO_SI_UID"
This symbol, if defined, indicates that "siginfo_t" has the "si_uid"
member
"HAS_SIGINFO_SI_VALUE"
This symbol, if defined, indicates that "siginfo_t" has the
"si_value" member
"PERL_SIGNALS_UNSAFE_FLAG"
If this bit in "PL_signals" is set, the system is uing the pre-Perl
5.8 unsafe signals. See "PERL_SIGNALS" in perlrun and "Deferred
Signals (Safe Signals)" in perlipc.
U32 PERL_SIGNALS_UNSAFE_FLAG
"rsignal"
A wrapper for the C library functions sigaction(2) or signal(2).
Use this instead of those libc functions, as the Perl version gives
the safest available implementation, and knows things that interact
with the rest of the perl interpreter.
Sighandler_t rsignal(int i, Sighandler_t t)
"rsignal_state"
Returns a the current signal handler for signal "signo". See
""rsignal"".
Sighandler_t rsignal_state(int i)
"Sigjmp_buf"
This is the buffer type to be used with Sigsetjmp and Siglongjmp.
"Siglongjmp"
This macro is used in the same way as siglongjmp(), but will invoke
traditional longjmp() if siglongjmp isn't available. See
"HAS_SIGSETJMP".
void Siglongjmp(jmp_buf env, int val)
"SIG_NAME"
This symbol contains a list of signal names in order of signal
number. This is intended to be used as a static array
initialization, like this:
char *sig_name[] = { SIG_NAME };
The signals in the list are separated with commas, and each signal
is surrounded by double quotes. There is no leading "SIG" in the
signal name, i.e. "SIGQUIT" is known as ""QUIT"". Gaps in the
signal numbers (up to "NSIG") are filled in with "NUMnn", etc.,
where nn is the actual signal number (e.g. "NUM37"). The signal
number for "sig_name[i]" is stored in "sig_num[i]". The last
element is 0 to terminate the list with a "NULL". This corresponds
to the 0 at the end of the "sig_name_init" list. Note that this
variable is initialized from the "sig_name_init", not from
"sig_name" (which is unused).
"SIG_NUM"
This symbol contains a list of signal numbers, in the same order as
the "SIG_NAME" list. It is suitable for static array initialization,
as in:
int sig_num[] = { SIG_NUM };
The signals in the list are separated with commas, and the indices
within that list and the "SIG_NAME" list match, so it's easy to
compute the signal name from a number or vice versa at the price of
a small dynamic linear lookup. Duplicates are allowed, but are
moved to the end of the list. The signal number corresponding to
"sig_name[i]" is "sig_number[i]". if (i < "NSIG") then
"sig_number[i]" == i. The last element is 0, corresponding to the 0
at the end of the "sig_name_init" list. Note that this variable is
initialized from the "sig_num_init", not from "sig_num" (which is
unused).
"Sigsetjmp"
This macro is used in the same way as sigsetjmp(), but will invoke
traditional setjmp() if sigsetjmp isn't available. See
"HAS_SIGSETJMP".
int Sigsetjmp(jmp_buf env, int savesigs)
"SIG_SIZE"
This variable contains the number of elements of the "SIG_NAME" and
"SIG_NUM" arrays, excluding the final "NULL" entry.
"whichsig"
"whichsig_pv"
"whichsig_pvn"
"whichsig_sv"
These all convert a signal name into its corresponding signal
number; returning -1 if no corresponding number was found.
They differ only in the source of the signal name:
"whichsig_pv" takes the name from the "NUL"-terminated string
starting at "sig".
"whichsig" is merely a different spelling, a synonym, of
"whichsig_pv".
"whichsig_pvn" takes the name from the string starting at "sig",
with length "len" bytes.
"whichsig_sv" takes the name from the PV stored in the SV "sigsv".
I32 whichsig (const char *sig)
I32 whichsig_pv (const char *sig)
I32 whichsig_pvn(const char *sig, STRLEN len)
I32 whichsig_sv (SV *sigsv)
Site configuration
These variables give details as to where various libraries, installation
destinations, etc., go, as well as what various installation options
were selected
"ARCHLIB"
This variable, if defined, holds the name of the directory in which
the user wants to put architecture-dependent public library files
for perl5. It is most often a local directory such as
/usr/local/lib. Programs using this variable must be prepared to
deal with filename expansion. If "ARCHLIB" is the same as
"PRIVLIB", it is not defined, since presumably the program already
searches "PRIVLIB".
"ARCHLIB_EXP"
This symbol contains the ~name expanded version of "ARCHLIB", to be
used in programs that are not prepared to deal with ~ expansion at
run-time.
"ARCHNAME"
This symbol holds a string representing the architecture name. It
may be used to construct an architecture-dependant pathname where
library files may be held under a private library, for instance.
"BIN"
This symbol holds the path of the bin directory where the package
will be installed. Program must be prepared to deal with ~name
substitution.
"BIN_EXP"
This symbol is the filename expanded version of the "BIN" symbol,
for programs that do not want to deal with that at run-time.
"INSTALL_USR_BIN_PERL"
This symbol, if defined, indicates that Perl is to be installed also
as /usr/bin/perl.
"MULTIARCH"
This symbol, if defined, signifies that the build process will
produce some binary files that are going to be used in a cross-
platform environment. This is the case for example with the NeXT
"fat" binaries that contain executables for several "CPUs".
"PERL_INC_VERSION_LIST"
This variable specifies the list of subdirectories in over which
perl.c:incpush() and lib/lib.pm will automatically search when
adding directories to @"INC", in a format suitable for a C
initialization string. See the "inc_version_list" entry in
Porting/Glossary for more details.
"PERL_OTHERLIBDIRS"
This variable contains a colon-separated set of paths for the perl
binary to search for additional library files or modules. These
directories will be tacked to the end of @"INC". Perl will
automatically search below each path for version- and architecture-
specific directories. See "PERL_INC_VERSION_LIST" for more details.
"PERL_RELOCATABLE_INC"
This symbol, if defined, indicates that we'd like to relocate
entries in @"INC" at run time based on the location of the perl
binary.
"PERL_TARGETARCH"
This symbol, if defined, indicates the target architecture Perl has
been cross-compiled to. Undefined if not a cross-compile.
"PERL_USE_DEVEL"
This symbol, if defined, indicates that Perl was configured with
"-Dusedevel", to enable development features. This should not be
done for production builds.
"PERL_VENDORARCH"
If defined, this symbol contains the name of a private library. The
library is private in the sense that it needn't be in anyone's
execution path, but it should be accessible by the world. It may
have a ~ on the front. The standard distribution will put nothing
in this directory. Vendors who distribute perl may wish to place
their own architecture-dependent modules and extensions in this
directory with
MakeMaker Makefile.PL INSTALLDIRS=vendor
or equivalent. See "INSTALL" for details.
"PERL_VENDORARCH_EXP"
This symbol contains the ~name expanded version of
"PERL_VENDORARCH", to be used in programs that are not prepared to
deal with ~ expansion at run-time.
"PERL_VENDORLIB_EXP"
This symbol contains the ~name expanded version of "VENDORLIB", to
be used in programs that are not prepared to deal with ~ expansion
at run-time.
"PERL_VENDORLIB_STEM"
This define is "PERL_VENDORLIB_EXP" with any trailing version-
specific component removed. The elements in "inc_version_list"
("inc_version_list".U (part of metaconfig)) can be tacked onto this
variable to generate a list of directories to search.
"PRIVLIB"
This symbol contains the name of the private library for this
package. The library is private in the sense that it needn't be in
anyone's execution path, but it should be accessible by the world.
The program should be prepared to do ~ expansion.
"PRIVLIB_EXP"
This symbol contains the ~name expanded version of "PRIVLIB", to be
used in programs that are not prepared to deal with ~ expansion at
run-time.
"SITEARCH"
This symbol contains the name of the private library for this
package. The library is private in the sense that it needn't be in
anyone's execution path, but it should be accessible by the world.
The program should be prepared to do ~ expansion. The standard
distribution will put nothing in this directory. After perl has
been installed, users may install their own local architecture-
dependent modules in this directory with
MakeMaker Makefile.PL
or equivalent. See "INSTALL" for details.
"SITEARCH_EXP"
This symbol contains the ~name expanded version of "SITEARCH", to be
used in programs that are not prepared to deal with ~ expansion at
run-time.
"SITELIB"
This symbol contains the name of the private library for this
package. The library is private in the sense that it needn't be in
anyone's execution path, but it should be accessible by the world.
The program should be prepared to do ~ expansion. The standard
distribution will put nothing in this directory. After perl has
been installed, users may install their own local architecture-
independent modules in this directory with
MakeMaker Makefile.PL
or equivalent. See "INSTALL" for details.
"SITELIB_EXP"
This symbol contains the ~name expanded version of "SITELIB", to be
used in programs that are not prepared to deal with ~ expansion at
run-time.
"SITELIB_STEM"
This define is "SITELIB_EXP" with any trailing version-specific
component removed. The elements in "inc_version_list"
("inc_version_list".U (part of metaconfig)) can be tacked onto this
variable to generate a list of directories to search.
"STARTPERL"
This variable contains the string to put in front of a perl script
to make sure (one hopes) that it runs with perl and not some shell.
"USE_64_BIT_ALL"
This symbol, if defined, indicates that 64-bit integers should be
used when available. If not defined, the native integers will be
used (be they 32 or 64 bits). The maximal possible 64-bitness is
employed: LP64 or "ILP64", meaning that you will be able to use more
than 2 gigabytes of memory. This mode is even more binary
incompatible than "USE_64_BIT_INT". You may not be able to run the
resulting executable in a 32-bit "CPU" at all or you may need at
least to reboot your OS to 64-bit mode.
"USE_64_BIT_INT"
This symbol, if defined, indicates that 64-bit integers should be
used when available. If not defined, the native integers will be
employed (be they 32 or 64 bits). The minimal possible 64-bitness
is used, just enough to get 64-bit integers into Perl. This may
mean using for example "long longs", while your memory may still be
limited to 2 gigabytes.
"USE_BSD_GETPGRP"
This symbol, if defined, indicates that getpgrp needs one arguments
whereas "USG" one needs none.
"USE_BSD_SETPGRP"
This symbol, if defined, indicates that setpgrp needs two arguments
whereas "USG" one needs none. See also "HAS_SETPGID" for a "POSIX"
interface.
"USE_C_BACKTRACE"
This symbol, if defined, indicates that Perl should be built with
support for backtrace.
"USE_CPLUSPLUS"
This symbol, if defined, indicates that a C++ compiler was used to
compiled Perl and will be used to compile extensions.
"USE_CROSS_COMPILE"
This symbol, if defined, indicates that Perl is being cross-
compiled.
"USE_DTRACE"
This symbol, if defined, indicates that Perl should be built with
support for DTrace.
"USE_DYNAMIC_LOADING"
This symbol, if defined, indicates that dynamic loading of some sort
is available.
"USE_FAST_STDIO"
This symbol, if defined, indicates that Perl should be built to use
'fast stdio'. Defaults to define in Perls 5.8 and earlier, to undef
later.
"USE_ITHREADS"
This symbol, if defined, indicates that Perl should be built to use
the interpreter-based threading implementation.
"USE_KERN_PROC_PATHNAME"
This symbol, if defined, indicates that we can use sysctl with
"KERN_PROC_PATHNAME" to get a full path for the executable, and
hence convert $^X to an absolute path.
"USE_LARGE_FILES"
This symbol, if defined, indicates that large file support should be
used when available.
"USE_LONG_DOUBLE"
This symbol, if defined, indicates that long doubles should be used
when available.
"USE_MORE_BITS"
This symbol, if defined, indicates that 64-bit interfaces and long
doubles should be used when available.
"USE_NSGETEXECUTABLEPATH"
This symbol, if defined, indicates that we can use
"_NSGetExecutablePath" and realpath to get a full path for the
executable, and hence convert $^X to an absolute path.
"USE_PERLIO"
This symbol, if defined, indicates that the PerlIO abstraction
should be used throughout. If not defined, stdio should be used in
a fully backward compatible manner.
"USE_QUADMATH"
This symbol, if defined, indicates that the quadmath library should
be used when available.
"USE_REENTRANT_API"
This symbol, if defined, indicates that Perl should try to use the
various "_r" versions of library functions. This is extremely
experimental.
"USE_SEMCTL_SEMID_DS"
This symbol, if defined, indicates that "struct semid_ds" * is used
for semctl "IPC_STAT".
"USE_SEMCTL_SEMUN"
This symbol, if defined, indicates that "union semun" is used for
semctl "IPC_STAT".
"USE_SITECUSTOMIZE"
This symbol, if defined, indicates that sitecustomize should be
used.
"USE_SOCKS"
This symbol, if defined, indicates that Perl should be built to use
socks.
"USE_STAT_BLOCKS"
This symbol is defined if this system has a stat structure declaring
"st_blksize" and "st_blocks".
"USE_STDIO_BASE"
This symbol is defined if the "_base" field (or similar) of the
stdio "FILE" structure can be used to access the stdio buffer for a
file handle. If this is defined, then the FILE_base(fp) macro will
also be defined and should be used to access this field. Also, the
FILE_bufsiz(fp) macro will be defined and should be used to
determine the number of bytes in the buffer. "USE_STDIO_BASE" will
never be defined unless "USE_STDIO_PTR" is.
"USE_STDIO_PTR"
This symbol is defined if the "_ptr" and "_cnt" fields (or similar)
of the stdio "FILE" structure can be used to access the stdio buffer
for a file handle. If this is defined, then the FILE_ptr(fp) and
FILE_cnt(fp) macros will also be defined and should be used to
access these fields.
"USE_STRICT_BY_DEFAULT"
This symbol, if defined, enables additional defaults. At this time
it only enables implicit strict by default.
"USE_THREADS"
This symbol, if defined, indicates that Perl should be built to use
threads. At present, it is a synonym for and "USE_ITHREADS", but
eventually the source ought to be changed to use this to mean
"_any_" threading implementation.
Sockets configuration values
"HAS_SOCKADDR_IN6"
This symbol, if defined, indicates the availability of "struct
sockaddr_in6";
"HAS_SOCKADDR_SA_LEN"
This symbol, if defined, indicates that the "struct sockaddr"
structure has a member called "sa_len", indicating the length of the
structure.
"HAS_SOCKADDR_STORAGE"
This symbol, if defined, indicates the availability of "struct
sockaddr_storage";
"HAS_SOCKATMARK"
This symbol, if defined, indicates that the "sockatmark" routine is
available to test whether a socket is at the out-of-band mark.
"HAS_SOCKET"
This symbol, if defined, indicates that the "BSD" "socket" interface
is supported.
"HAS_SOCKETPAIR"
This symbol, if defined, indicates that the "BSD" socketpair() call
is supported.
"HAS_SOCKS5_INIT"
This symbol, if defined, indicates that the "socks5_init" routine is
available to initialize "SOCKS" 5.
"I_SOCKS"
This symbol, if defined, indicates that socks.h exists and should be
included.
#ifdef I_SOCKS
#include <socks.h>
#endif
"I_SYS_SOCKIO"
This symbol, if defined, indicates the sys/sockio.h should be
included to get socket ioctl options, like "SIOCATMARK".
#ifdef I_SYS_SOCKIO
#include <sys_sockio.h>
#endif
Source Filters
"apply_builtin_cv_attributes"
Given an OP_LIST containing attribute definitions, filter it for
known builtin attributes to apply to the cv, returning a possibly-
smaller list containing just the remaining ones.
OP * apply_builtin_cv_attributes(CV *cv, OP *attrlist)
"filter_add"
Described in perlfilter.
SV * filter_add(filter_t funcp, SV *datasv)
"filter_del"
Delete most recently added instance of the filter function argument
void filter_del(filter_t funcp)
"filter_read"
Described in perlfilter.
I32 filter_read(int idx, SV *buf_sv, int maxlen)
"scan_vstring"
Returns a pointer to the next character after the parsed vstring, as
well as updating the passed in sv.
Function must be called like
sv = sv_2mortal(newSV(5));
s = scan_vstring(s,e,sv);
where s and e are the start and end of the string. The sv should
already be large enough to store the vstring passed in, for
performance reasons.
This function may croak if fatal warnings are enabled in the calling
scope, hence the sv_2mortal in the example (to prevent a leak).
Make sure to do SvREFCNT_inc afterwards if you use sv_2mortal.
char * scan_vstring(const char *s, const char * const e, SV *sv)
"start_subparse"
Set things up for parsing a subroutine.
If "is_format" is non-zero, the input is to be considered a format
sub (a specialised sub used to implement perl's "format" feature);
else a normal "sub".
"flags" are added to the flags for "PL_compcv". "flags" may include
the "CVf_IsMETHOD" bit, which causes the new subroutine to be a
method.
This returns the value of "PL_savestack_ix" that was in effect upon
entry to the function;
I32 start_subparse(I32 is_format, U32 flags)
Stack Manipulation Macros
"dMARK"
Declare a stack marker variable, "mark", for the XSUB. See "MARK"
and "dORIGMARK".
dMARK;
"dORIGMARK"
Saves the original stack mark for the XSUB. See "ORIGMARK".
dORIGMARK;
"dSP"
Declares a local copy of perl's stack pointer for the XSUB,
available via the "SP" macro. See "SP".
dSP;
"dTARGET"
Declare that this function uses "TARG", and initializes it
dTARGET;
"EXTEND"
Used to extend the argument stack for an XSUB's return values. Once
used, guarantees that there is room for at least "nitems" to be
pushed onto the stack.
void EXTEND(SP, SSize_t nitems)
"MARK"
Stack marker variable for the XSUB. See "dMARK".
"mPUSHi"
Push an integer onto the stack. The stack must have room for this
element. Does not use "TARG". See also "PUSHi", "mXPUSHi" and
"XPUSHi".
void mPUSHi(IV iv)
"mPUSHn"
Push a double onto the stack. The stack must have room for this
element. Does not use "TARG". See also "PUSHn", "mXPUSHn" and
"XPUSHn".
void mPUSHn(NV nv)
"mPUSHp"
Push a string onto the stack. The stack must have room for this
element. The "len" indicates the length of the string. Does not
use "TARG". See also "PUSHp", "mXPUSHp" and "XPUSHp".
void mPUSHp(char* str, STRLEN len)
"mPUSHpvs"
A variation on "mPUSHp" that takes a literal string and calculates
its size directly.
void mPUSHpvs("literal string")
"mPUSHs"
Push an SV onto the stack and mortalizes the SV. The stack must
have room for this element. Does not use "TARG". See also "PUSHs"
and "mXPUSHs".
void mPUSHs(SV* sv)
"mPUSHu"
Push an unsigned integer onto the stack. The stack must have room
for this element. Does not use "TARG". See also "PUSHu", "mXPUSHu"
and "XPUSHu".
void mPUSHu(UV uv)
"mXPUSHi"
Push an integer onto the stack, extending the stack if necessary.
Does not use "TARG". See also "XPUSHi", "mPUSHi" and "PUSHi".
void mXPUSHi(IV iv)
"mXPUSHn"
Push a double onto the stack, extending the stack if necessary.
Does not use "TARG". See also "XPUSHn", "mPUSHn" and "PUSHn".
void mXPUSHn(NV nv)
"mXPUSHp"
Push a string onto the stack, extending the stack if necessary. The
"len" indicates the length of the string. Does not use "TARG". See
also "XPUSHp", "mPUSHp" and "PUSHp".
void mXPUSHp(char* str, STRLEN len)
"mXPUSHpvs"
A variation on "mXPUSHp" that takes a literal string and calculates
its size directly.
void mXPUSHpvs("literal string")
"mXPUSHs"
Push an SV onto the stack, extending the stack if necessary and
mortalizes the SV. Does not use "TARG". See also "XPUSHs" and
"mPUSHs".
void mXPUSHs(SV* sv)
"mXPUSHu"
Push an unsigned integer onto the stack, extending the stack if
necessary. Does not use "TARG". See also "XPUSHu", "mPUSHu" and
"PUSHu".
void mXPUSHu(UV uv)
"newXSproto"
Used by "xsubpp" to hook up XSUBs as Perl subs. Adds Perl
prototypes to the subs.
"ORIGMARK"
The original stack mark for the XSUB. See "dORIGMARK".
"PL_markstack"
Described in perlguts.
"PL_markstack_ptr"
Described in perlguts.
"PL_savestack"
Described in perlguts.
"PL_savestack_ix"
Described in perlguts.
"PL_scopestack"
Described in perlguts.
"PL_scopestack_ix"
Described in perlguts.
"PL_scopestack_name"
Described in perlguts.
"PL_stack_base"
Described in perlguts.
"PL_stack_sp"
Described in perlguts.
"PL_tmps_floor"
Described in perlguts.
"PL_tmps_ix"
Described in perlguts.
"PL_tmps_stack"
Described in perlguts.
"POPi"
Pops an integer off the stack.
IV POPi
"POPl"
Pops a long off the stack.
long POPl
"POPn"
Pops a double off the stack.
NV POPn
"POPp"
Pops a string off the stack.
char* POPp
"POPpbytex"
Pops a string off the stack which must consist of bytes i.e.
characters < 256.
char* POPpbytex
"POPpx"
Pops a string off the stack. Identical to POPp. There are two
names for historical reasons.
char* POPpx
"POPs"
Pops an SV off the stack.
SV* POPs
"POPu"
Pops an unsigned integer off the stack.
UV POPu
"POPul"
Pops an unsigned long off the stack.
long POPul
"PUSHi"
Push an integer onto the stack. The stack must have room for this
element. Handles 'set' magic. Uses "TARG", so "dTARGET" or
"dXSTARG" should be called to declare it. Do not call multiple
"TARG"-oriented macros to return lists from XSUB's - see "mPUSHi"
instead. See also "XPUSHi" and "mXPUSHi".
void PUSHi(IV iv)
"PUSHMARK"
Opening bracket for arguments on a callback. See "PUTBACK" and
perlcall.
void PUSHMARK(SP)
"PUSHmortal"
Push a new mortal SV onto the stack. The stack must have room for
this element. Does not use "TARG". See also "PUSHs", "XPUSHmortal"
and "XPUSHs".
void PUSHmortal
"PUSHn"
Push a double onto the stack. The stack must have room for this
element. Handles 'set' magic. Uses "TARG", so "dTARGET" or
"dXSTARG" should be called to declare it. Do not call multiple
"TARG"-oriented macros to return lists from XSUB's - see "mPUSHn"
instead. See also "XPUSHn" and "mXPUSHn".
void PUSHn(NV nv)
"PUSHp"
Push a string onto the stack. The stack must have room for this
element. The "len" indicates the length of the string. Handles
'set' magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be
called to declare it. Do not call multiple "TARG"-oriented macros
to return lists from XSUB's - see "mPUSHp" instead. See also
"XPUSHp" and "mXPUSHp".
void PUSHp(char* str, STRLEN len)
"PUSHpvs"
A variation on "PUSHp" that takes a literal string and calculates
its size directly.
void PUSHpvs("literal string")
"PUSHs"
Push an SV onto the stack. The stack must have room for this
element. Does not handle 'set' magic. Does not use "TARG". See
also "PUSHmortal", "XPUSHs", and "XPUSHmortal".
void PUSHs(SV* sv)
"PUSHu"
Push an unsigned integer onto the stack. The stack must have room
for this element. Handles 'set' magic. Uses "TARG", so "dTARGET"
or "dXSTARG" should be called to declare it. Do not call multiple
"TARG"-oriented macros to return lists from XSUB's - see "mPUSHu"
instead. See also "XPUSHu" and "mXPUSHu".
void PUSHu(UV uv)
"PUTBACK"
Closing bracket for XSUB arguments. This is usually handled by
"xsubpp". See "PUSHMARK" and perlcall for other uses.
PUTBACK;
"SAVEt_INT"
Described in perlguts.
"SP"
Stack pointer. This is usually handled by "xsubpp". See "dSP" and
"SPAGAIN".
"SPAGAIN"
Refetch the stack pointer. Used after a callback. See perlcall.
SPAGAIN;
"SSNEW"
"SSNEWa"
"SSNEWat"
"SSNEWt"
These each temporarily allocate data on the savestack, returning an
SSize_t index into the savestack, because a pointer would get broken
if the savestack is moved on reallocation. Use ""SSPTR"" to convert
the returned index into a pointer.
The forms differ in that plain "SSNEW" allocates "size" bytes;
"SSNEWt" and "SSNEWat" allocate "size" objects, each of which is
type "type"; and <SSNEWa> and "SSNEWat" make sure to align the new
data to an "align" boundary. The most useful value for the
alignment is likely to be ""MEM_ALIGNBYTES"". The alignment will be
preserved through savestack reallocation only if realloc returns
data aligned to a size divisible by "align"!
SSize_t SSNEW (Size_t size)
SSize_t SSNEWa (Size_t size, Size_t align)
SSize_t SSNEWat(Size_t size, type, Size_t align)
SSize_t SSNEWt (Size_t size, type)
"SSPTR"
"SSPTRt"
These convert the "index" returned by L/<"SSNEW"> and kin into
actual pointers.
The difference is that "SSPTR" casts the result to "type", and
"SSPTRt" casts it to a pointer of that "type".
type SSPTR (SSize_t index, type)
type * SSPTRt(SSize_t index, type)
"TARG"
"TARG" is short for "target". It is an entry in the pad that an OPs
"op_targ" refers to. It is scratchpad space, often used as a return
value for the OP, but some use it for other purposes.
TARG;
"TOPs"
Described in perlguts.
"XPUSHi"
Push an integer onto the stack, extending the stack if necessary.
Handles 'set' magic. Uses "TARG", so "dTARGET" or "dXSTARG" should
be called to declare it. Do not call multiple "TARG"-oriented
macros to return lists from XSUB's - see "mXPUSHi" instead. See
also "PUSHi" and "mPUSHi".
void XPUSHi(IV iv)
"XPUSHmortal"
Push a new mortal SV onto the stack, extending the stack if
necessary. Does not use "TARG". See also "XPUSHs", "PUSHmortal"
and "PUSHs".
void XPUSHmortal
"XPUSHn"
Push a double onto the stack, extending the stack if necessary.
Handles 'set' magic. Uses "TARG", so "dTARGET" or "dXSTARG" should
be called to declare it. Do not call multiple "TARG"-oriented
macros to return lists from XSUB's - see "mXPUSHn" instead. See
also "PUSHn" and "mPUSHn".
void XPUSHn(NV nv)
"XPUSHp"
Push a string onto the stack, extending the stack if necessary. The
"len" indicates the length of the string. Handles 'set' magic.
Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare
it. Do not call multiple "TARG"-oriented macros to return lists
from XSUB's - see "mXPUSHp" instead. See also "PUSHp" and "mPUSHp".
void XPUSHp(char* str, STRLEN len)
"XPUSHpvs"
A variation on "XPUSHp" that takes a literal string and calculates
its size directly.
void XPUSHpvs("literal string")
"XPUSHs"
Push an SV onto the stack, extending the stack if necessary. Does
not handle 'set' magic. Does not use "TARG". See also
"XPUSHmortal", "PUSHs" and "PUSHmortal".
void XPUSHs(SV* sv)
"XPUSHu"
Push an unsigned integer onto the stack, extending the stack if
necessary. Handles 'set' magic. Uses "TARG", so "dTARGET" or
"dXSTARG" should be called to declare it. Do not call multiple
"TARG"-oriented macros to return lists from XSUB's - see "mXPUSHu"
instead. See also "PUSHu" and "mPUSHu".
void XPUSHu(UV uv)
"XS_APIVERSION_BOOTCHECK"
Macro to verify that the perl api version an XS module has been
compiled against matches the api version of the perl interpreter
it's being loaded into.
XS_APIVERSION_BOOTCHECK;
"XSRETURN"
Return from XSUB, indicating number of items on the stack. This is
usually handled by "xsubpp".
void XSRETURN(int nitems)
"XSRETURN_EMPTY"
Return an empty list from an XSUB immediately.
XSRETURN_EMPTY;
"XSRETURN_IV"
Return an integer from an XSUB immediately. Uses "XST_mIV".
void XSRETURN_IV(IV iv)
"XSRETURN_NO"
Return &PL_sv_no from an XSUB immediately. Uses "XST_mNO".
XSRETURN_NO;
"XSRETURN_NV"
Return a double from an XSUB immediately. Uses "XST_mNV".
void XSRETURN_NV(NV nv)
"XSRETURN_PV"
Return a copy of a string from an XSUB immediately. Uses "XST_mPV".
void XSRETURN_PV(char* str)
"XSRETURN_UNDEF"
Return &PL_sv_undef from an XSUB immediately. Uses "XST_mUNDEF".
XSRETURN_UNDEF;
"XSRETURN_UV"
Return an integer from an XSUB immediately. Uses "XST_mUV".
void XSRETURN_UV(IV uv)
"XSRETURN_YES"
Return &PL_sv_yes from an XSUB immediately. Uses "XST_mYES".
XSRETURN_YES;
"XST_mIV"
Place an integer into the specified position "pos" on the stack.
The value is stored in a new mortal SV.
void XST_mIV(int pos, IV iv)
"XST_mNO"
Place &PL_sv_no into the specified position "pos" on the stack.
void XST_mNO(int pos)
"XST_mNV"
Place a double into the specified position "pos" on the stack. The
value is stored in a new mortal SV.
void XST_mNV(int pos, NV nv)
"XST_mPV"
Place a copy of a string into the specified position "pos" on the
stack. The value is stored in a new mortal SV.
void XST_mPV(int pos, char* str)
"XST_mUNDEF"
Place &PL_sv_undef into the specified position "pos" on the stack.
void XST_mUNDEF(int pos)
"XST_mUV"
Place an unsigned integer into the specified position "pos" on the
stack. The value is stored in a new mortal SV.
void XST_mUV(int pos, UV uv)
"XST_mYES"
Place &PL_sv_yes into the specified position "pos" on the stack.
void XST_mYES(int pos)
"XS_VERSION"
The version identifier for an XS module. This is usually handled
automatically by "ExtUtils::MakeMaker". See "XS_VERSION_BOOTCHECK".
"XS_VERSION_BOOTCHECK"
Macro to verify that a PM module's $VERSION variable matches the XS
module's "XS_VERSION" variable. This is usually handled
automatically by "xsubpp". See "The VERSIONCHECK: Keyword" in
perlxs.
XS_VERSION_BOOTCHECK;
String Handling
See also "Unicode Support".
"CAT2"
This macro concatenates 2 tokens together.
token CAT2(token x, token y)
"Copy"
"CopyD"
The XSUB-writer's interface to the C "memcpy" function. The "src"
is the source, "dest" is the destination, "nitems" is the number of
items, and "type" is the type. May fail on overlapping copies. See
also "Move".
"CopyD" is like "Copy" but returns "dest". Useful for encouraging
compilers to tail-call optimise.
void Copy (void* src, void* dest, int nitems, type)
void * CopyD(void* src, void* dest, int nitems, type)
"delimcpy"
Copy a source buffer to a destination buffer, stopping at (but not
including) the first occurrence in the source of an unescaped
(defined below) delimiter byte, "delim". The source is the bytes
between "from" and "from_end" - 1. Similarly, the dest is "to" up
to "to_end".
The number of bytes copied is written to *retlen.
Returns the position of the first uncopied "delim" in the "from"
buffer, but if there is no such occurrence before "from_end", then
"from_end" is returned, and the entire buffer
"from" .. "from_end" - 1 is copied.
If there is room in the destination available after the copy, an
extra terminating safety "NUL" byte is appended (not included in the
returned length).
The error case is if the destination buffer is not large enough to
accommodate everything that should be copied. In this situation, a
value larger than "to_end" - "to" is written to *retlen, and as much
of the source as fits will be written to the destination. Not
having room for the safety "NUL" is not considered an error.
In the following examples, let "x" be the delimiter, and 0 represent
a "NUL" byte (NOT the digit 0). Then we would have
Source Destination
abcxdef abc0
provided the destination buffer is at least 4 bytes long.
An escaped delimiter is one which is immediately preceded by a
single backslash. Escaped delimiters are copied, and the copy
continues past the delimiter; the backslash is not copied:
Source Destination
abc\xdef abcxdef0
(provided the destination buffer is at least 8 bytes long).
It's actually somewhat more complicated than that. A sequence of any
odd number of backslashes escapes the following delimiter, and the
copy continues with exactly one of the backslashes stripped.
Source Destination
abc\xdef abcxdef0
abc\\\xdef abc\\xdef0
abc\\\\\xdef abc\\\\xdef0
(as always, if the destination is large enough)
An even number of preceding backslashes does not escape the
delimiter, so that the copy stops just before it, and includes all
the backslashes (no stripping; zero is considered even):
Source Destination
abcxdef abc0
abc\\xdef abc\\0
abc\\\\xdef abc\\\\0
char * delimcpy(char *to, const char *to_end, const char *from,
const char *from_end, const int delim,
I32 *retlen)
"do_join"
This performs a Perl "join", placing the joined output into "sv".
The elements to join are in SVs, stored in a C array of pointers to
SVs, from **mark to "**sp - 1". Hence *mark is a reference to the
first SV. Each SV will be coerced into a PV if not one already.
"delim" contains the string (or coerced into a string) that is to
separate each of the joined elements.
If any component is in UTF-8, the result will be as well, and all
non-UTF-8 components will be converted to UTF-8 as necessary.
Magic and tainting are handled.
void do_join(SV *sv, SV *delim, SV **mark, SV **sp)
"do_sprintf"
This performs a Perl "sprintf" placing the string output into "sv".
The elements to format are in SVs, stored in a C array of pointers
to SVs of length "len"> and beginning at **sarg. The element
referenced by *sarg is the format.
Magic and tainting are handled.
void do_sprintf(SV *sv, SSize_t len, SV **sarg)
"fbm_compile"
Analyzes the string in order to make fast searches on it using
fbm_instr() -- the Boyer-Moore algorithm.
void fbm_compile(SV *sv, U32 flags)
"fbm_instr"
Returns the location of the SV in the string delimited by "big" and
"bigend" ("bigend") is the char following the last char). It
returns "NULL" if the string can't be found. The "sv" does not have
to be "fbm_compiled", but the search will not be as fast then.
char * fbm_instr(unsigned char *big, unsigned char *bigend,
SV *littlestr, U32 flags)
"foldEQ"
Returns true if the leading "len" bytes of the strings "s1" and "s2"
are the same case-insensitively; false otherwise. Uppercase and
lowercase ASCII range bytes match themselves and their opposite case
counterparts. Non-cased and non-ASCII range bytes match only
themselves.
I32 foldEQ(const char *a, const char *b, I32 len)
"ibcmp"
This is a synonym for "(! foldEQ())"
I32 ibcmp(const char *a, const char *b, I32 len)
"ibcmp_locale"
This is a synonym for "(! foldEQ_locale())"
I32 ibcmp_locale(const char *a, const char *b, I32 len)
"ibcmp_utf8"
This is a synonym for "(! foldEQ_utf8())"
I32 ibcmp_utf8(const char *s1, char **pe1, UV l1, bool u1,
const char *s2, char **pe2, UV l2, bool u2)
"instr"
Same as strstr(3), which finds and returns a pointer to the first
occurrence of the NUL-terminated substring "little" in the NUL-
terminated string "big", returning NULL if not found. The
terminating NUL bytes are not compared.
char * instr(const char *big, const char *little)
"memCHRs"
Returns the position of the first occurrence of the byte "c" in the
literal string "list", or NULL if "c" doesn't appear in "list". All
bytes are treated as unsigned char. Thus this macro can be used to
determine if "c" is in a set of particular characters. Unlike
strchr(3), it works even if "c" is "NUL" (and the set doesn't
include "NUL").
bool memCHRs("list", char c)
"memEQ"
Test two buffers (which may contain embedded "NUL" characters, to
see if they are equal. The "len" parameter indicates the number of
bytes to compare. Returns true or false. It is undefined behavior
if either of the buffers doesn't contain at least "len" bytes.
bool memEQ(char* s1, char* s2, STRLEN len)
"memEQs"
Like "memEQ", but the second string is a literal enclosed in double
quotes, "l1" gives the number of bytes in "s1". Returns true or
false.
bool memEQs(char* s1, STRLEN l1, "s2")
"memNE"
Test two buffers (which may contain embedded "NUL" characters, to
see if they are not equal. The "len" parameter indicates the number
of bytes to compare. Returns true or false. It is undefined
behavior if either of the buffers doesn't contain at least "len"
bytes.
bool memNE(char* s1, char* s2, STRLEN len)
"memNEs"
Like "memNE", but the second string is a literal enclosed in double
quotes, "l1" gives the number of bytes in "s1". Returns true or
false.
bool memNEs(char* s1, STRLEN l1, "s2")
"Move"
"MoveD"
The XSUB-writer's interface to the C "memmove" function. The "src"
is the source, "dest" is the destination, "nitems" is the number of
items, and "type" is the type. Can do overlapping moves. See also
"Copy".
"MoveD" is like "Move" but returns "dest". Useful for encouraging
compilers to tail-call optimise.
void Move (void* src, void* dest, int nitems, type)
void * MoveD(void* src, void* dest, int nitems, type)
"my_snprintf"
The C library "snprintf" functionality, if available and standards-
compliant (uses "vsnprintf", actually). However, if the "vsnprintf"
is not available, will unfortunately use the unsafe "vsprintf" which
can overrun the buffer (there is an overrun check, but that may be
too late). Consider using "sv_vcatpvf" instead, or getting
"vsnprintf".
int my_snprintf(char *buffer, const Size_t len,
const char *format, ...)
"my_sprintf"
"DEPRECATED!" It is planned to remove "my_sprintf" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Do NOT use this due to the possibility of overflowing "buffer".
Instead use my_snprintf()
int my_sprintf(NN char *buffer, NN const char *pat, ...)
"my_strnlen"
The C library "strnlen" if available, or a Perl implementation of
it.
my_strnlen() computes the length of the string, up to "maxlen"
bytes. It will never attempt to address more than "maxlen" bytes,
making it suitable for use with strings that are not guaranteed to
be NUL-terminated.
Size_t my_strnlen(const char *str, Size_t maxlen)
"my_vsnprintf"
The C library "vsnprintf" if available and standards-compliant.
However, if the "vsnprintf" is not available, will unfortunately use
the unsafe "vsprintf" which can overrun the buffer (there is an
overrun check, but that may be too late). Consider using
"sv_vcatpvf" instead, or getting "vsnprintf".
int my_vsnprintf(char *buffer, const Size_t len,
const char *format, va_list ap)
"NewCopy"
Combines Newx() and Copy() into a single macro. Dest will be
allocated using Newx() and then src will be copied into it.
void NewCopy(void* src, void* dest, int nitems, type)
"ninstr"
Find the first (leftmost) occurrence of a sequence of bytes within
another sequence. This is the Perl version of strstr(), extended to
handle arbitrary sequences, potentially containing embedded "NUL"
characters ("NUL" is what the initial "n" in the function name
stands for; some systems have an equivalent, memmem(), but with a
somewhat different API).
Another way of thinking about this function is finding a needle in a
haystack. "big" points to the first byte in the haystack.
"big_end" points to one byte beyond the final byte in the haystack.
"little" points to the first byte in the needle. "little_end"
points to one byte beyond the final byte in the needle. All the
parameters must be non-"NULL".
The function returns "NULL" if there is no occurrence of "little"
within "big". If "little" is the empty string, "big" is returned.
Because this function operates at the byte level, and because of the
inherent characteristics of UTF-8 (or UTF-EBCDIC), it will work
properly if both the needle and the haystack are strings with the
same UTF-8ness, but not if the UTF-8ness differs.
char * ninstr(const char *big, const char *bigend,
const char *little, const char *lend)
"Nullch"
Null character pointer. (No longer available when "PERL_CORE" is
defined.)
"PL_na"
A scratch pad variable in which to store a "STRLEN" value. If would
have been better named something like "PL_temp_strlen".
It is is typically used with "SvPV" when one is actually planning to
discard the returned length, (hence the length is "Not Applicable",
which is how this variable got its name).
BUT BEWARE, if this is used in a situation where something that is
using it is in a call stack with something else that is using it,
this variable would get zapped, leading to hard-to-diagnose errors.
It is usually more efficient to either declare a local variable and
use that instead, or to use the "SvPV_nolen" macro.
STRLEN PL_na
"rninstr"
Like "ninstr", but instead finds the final (rightmost) occurrence of
a sequence of bytes within another sequence, returning "NULL" if
there is no such occurrence.
char * rninstr(const char *big, const char *bigend,
const char *little, const char *lend)
"savepv"
Perl's version of strdup(). Returns a pointer to a newly allocated
string which is a duplicate of "pv". The size of the string is
determined by strlen(), which means it may not contain embedded
"NUL" characters and must have a trailing "NUL". To prevent memory
leaks, the memory allocated for the new string needs to be freed
when no longer needed. This can be done with the "Safefree"
function, or "SAVEFREEPV".
On some platforms, Windows for example, all allocated memory owned
by a thread is deallocated when that thread ends. So if you need
that not to happen, you need to use the shared memory functions,
such as "savesharedpv".
char * savepv(const char *pv)
"savepvn"
Perl's version of what strndup() would be if it existed. Returns a
pointer to a newly allocated string which is a duplicate of the
first "len" bytes from "pv", plus a trailing "NUL" byte. The memory
allocated for the new string can be freed with the Safefree()
function.
On some platforms, Windows for example, all allocated memory owned
by a thread is deallocated when that thread ends. So if you need
that not to happen, you need to use the shared memory functions,
such as "savesharedpvn".
char * savepvn(const char *pv, Size_t len)
"savepvs"
Like "savepvn", but takes a literal string instead of a
string/length pair.
char* savepvs("literal string")
"savesharedpv"
A version of savepv() which allocates the duplicate string in memory
which is shared between threads.
char * savesharedpv(const char *pv)
"savesharedpvn"
A version of savepvn() which allocates the duplicate string in
memory which is shared between threads. (With the specific
difference that a "NULL" pointer is not acceptable)
char * savesharedpvn(const char * const pv, const STRLEN len)
"savesharedpvs"
A version of savepvs() which allocates the duplicate string in
memory which is shared between threads.
char* savesharedpvs("literal string")
"savesharedsvpv"
A version of savesharedpv() which allocates the duplicate string in
memory which is shared between threads.
char * savesharedsvpv(SV *sv)
"savesvpv"
A version of savepv()/savepvn() which gets the string to duplicate
from the passed in SV using SvPV()
On some platforms, Windows for example, all allocated memory owned
by a thread is deallocated when that thread ends. So if you need
that not to happen, you need to use the shared memory functions,
such as "savesharedsvpv".
char * savesvpv(SV *sv)
"strEQ"
Test two "NUL"-terminated strings to see if they are equal. Returns
true or false.
bool strEQ(char* s1, char* s2)
"strGE"
Test two "NUL"-terminated strings to see if the first, "s1", is
greater than or equal to the second, "s2". Returns true or false.
bool strGE(char* s1, char* s2)
"strGT"
Test two "NUL"-terminated strings to see if the first, "s1", is
greater than the second, "s2". Returns true or false.
bool strGT(char* s1, char* s2)
"STRINGIFY"
This macro surrounds its token with double quotes.
string STRINGIFY(token x)
"strLE"
Test two "NUL"-terminated strings to see if the first, "s1", is less
than or equal to the second, "s2". Returns true or false.
bool strLE(char* s1, char* s2)
"STRLEN"
Described in perlguts.
"strLT"
Test two "NUL"-terminated strings to see if the first, "s1", is less
than the second, "s2". Returns true or false.
bool strLT(char* s1, char* s2)
"strNE"
Test two "NUL"-terminated strings to see if they are different.
Returns true or false.
bool strNE(char* s1, char* s2)
"strnEQ"
Test two "NUL"-terminated strings to see if they are equal. The
"len" parameter indicates the number of bytes to compare. Returns
true or false. (A wrapper for "strncmp").
bool strnEQ(char* s1, char* s2, STRLEN len)
"strnNE"
Test two "NUL"-terminated strings to see if they are different. The
"len" parameter indicates the number of bytes to compare. Returns
true or false. (A wrapper for "strncmp").
bool strnNE(char* s1, char* s2, STRLEN len)
"STR_WITH_LEN"
Returns two comma separated tokens of the input literal string, and
its length. This is convenience macro which helps out in some API
calls. Note that it can't be used as an argument to macros or
functions that under some configurations might be macros, which
means that it requires the full Perl_xxx(aTHX_ ...) form for any API
calls where it's used.
pair STR_WITH_LEN("literal string")
"Zero"
"ZeroD"
The XSUB-writer's interface to the C "memzero" function. The "dest"
is the destination, "nitems" is the number of items, and "type" is
the type.
"ZeroD" is like "Zero" but returns "dest". Useful for encouraging
compilers to tail-call optimise.
void Zero (void* dest, int nitems, type)
void * ZeroD(void* dest, int nitems, type)
SV Flags
"SVt_IV"
Type flag for scalars. See "svtype".
"SVt_NULL"
Type flag for scalars. See "svtype".
"SVt_NV"
Type flag for scalars. See "svtype".
"SVt_PV"
Type flag for scalars. See "svtype".
"SVt_PVAV"
Type flag for arrays. See "svtype".
"SVt_PVCV"
Type flag for subroutines. See "svtype".
"SVt_PVFM"
Type flag for formats. See "svtype".
"SVt_PVGV"
Type flag for typeglobs. See "svtype".
"SVt_PVHV"
Type flag for hashes. See "svtype".
"SVt_PVIO"
Type flag for I/O objects. See "svtype".
"SVt_PVIV"
Type flag for scalars. See "svtype".
"SVt_PVLV"
Type flag for scalars. See "svtype".
"SVt_PVMG"
Type flag for scalars. See "svtype".
"SVt_PVNV"
Type flag for scalars. See "svtype".
"SVt_PVOBJ"
NOTE: "SVt_PVOBJ" is experimental and may change or be removed
without notice.
Type flag for object instances. See "svtype".
"SVt_REGEXP"
Type flag for regular expressions. See "svtype".
"svtype"
An enum of flags for Perl types. These are found in the file sv.h
in the "svtype" enum. Test these flags with the "SvTYPE" macro.
The types are:
SVt_NULL
SVt_IV
SVt_NV
SVt_RV
SVt_PV
SVt_PVIV
SVt_PVNV
SVt_PVMG
SVt_INVLIST
SVt_REGEXP
SVt_PVGV
SVt_PVLV
SVt_PVAV
SVt_PVHV
SVt_PVCV
SVt_PVFM
SVt_PVIO
SVt_PVOBJ
These are most easily explained from the bottom up.
"SVt_PVOBJ" is for object instances of the new `use feature 'class'`
kind. "SVt_PVIO" is for I/O objects, "SVt_PVFM" for formats,
"SVt_PVCV" for subroutines, "SVt_PVHV" for hashes and "SVt_PVAV" for
arrays.
All the others are scalar types, that is, things that can be bound
to a "$" variable. For these, the internal types are mostly
orthogonal to types in the Perl language.
Hence, checking "SvTYPE(sv) < SVt_PVAV" is the best way to see
whether something is a scalar.
"SVt_PVGV" represents a typeglob. If "!SvFAKE(sv)", then it is a
real, incoercible typeglob. If SvFAKE(sv), then it is a scalar to
which a typeglob has been assigned. Assigning to it again will stop
it from being a typeglob. "SVt_PVLV" represents a scalar that
delegates to another scalar behind the scenes. It is used, e.g.,
for the return value of "substr" and for tied hash and array
elements. It can hold any scalar value, including a typeglob.
"SVt_REGEXP" is for regular expressions. "SVt_INVLIST" is for Perl
core internal use only.
"SVt_PVMG" represents a "normal" scalar (not a typeglob, regular
expression, or delegate). Since most scalars do not need all the
internal fields of a PVMG, we save memory by allocating smaller
structs when possible. All the other types are just simpler forms
of "SVt_PVMG", with fewer internal fields. "SVt_NULL" can only hold
undef. "SVt_IV" can hold undef, an integer, or a reference.
("SVt_RV" is an alias for "SVt_IV", which exists for backward
compatibility.) "SVt_NV" can hold undef or a double. (In builds
that support headless NVs, these could also hold a reference via a
suitable offset, in the same way that SVt_IV does, but this is not
currently supported and seems to be a rare use case.) "SVt_PV" can
hold "undef", a string, or a reference. "SVt_PVIV" is a superset of
"SVt_PV" and "SVt_IV". "SVt_PVNV" is a superset of "SVt_PV" and
"SVt_NV". "SVt_PVMG" can hold anything "SVt_PVNV" can hold, but it
may also be blessed or magical.
SV Handling
"AV_FROM_REF"
"CV_FROM_REF"
"HV_FROM_REF"
The "*V_FROM_REF" macros extract the SvRV() from a given reference
SV and return a suitably-cast to pointer to the referenced SV. When
running under "-DDEBUGGING", assertions are also applied that check
that ref is definitely a reference SV that refers to an SV of the
right type.
AV * AV_FROM_REF(SV * ref)
CV * CV_FROM_REF(SV * ref)
HV * HV_FROM_REF(SV * ref)
"BOOL_INTERNALS_sv_isbool"
Checks if a SvBoolFlagsOK() sv is a bool. Note that it is the
caller's responsibility to ensure that the sv is SvBoolFlagsOK()
before calling this. This is only useful in specialized logic like
serialization code where performance is critical and the flags have
already been checked to be correct. Almost always you should be
using sv_isbool(sv) instead.
bool BOOL_INTERNALS_sv_isbool(SV* sv)
"BOOL_INTERNALS_sv_isbool_false"
Checks if a SvBoolFlagsOK() sv is a false bool. Note that it is the
caller's responsibility to ensure that the sv is SvBoolFlagsOK()
before calling this. This is only useful in specialized logic like
serialization code where performance is critical and the flags have
already been checked to be correct. This is NOT what you should use
to check if an SV is "false", for that you should be using
"!SvTRUE(sv)" instead.
bool BOOL_INTERNALS_sv_isbool_false(SV* sv)
"BOOL_INTERNALS_sv_isbool_true"
Checks if a SvBoolFlagsOK() sv is a true bool. Note that it is the
caller's responsibility to ensure that the sv is SvBoolFlagsOK()
before calling this. This is only useful in specialized logic like
serialization code where performance is critical and the flags have
already been checked to be correct. This is NOT what you should use
to check if an SV is "true", for that you should be using SvTRUE(sv)
instead.
bool BOOL_INTERNALS_sv_isbool_true(SV* sv)
"boolSV"
Returns a true SV if "b" is a true value, or a false SV if "b" is 0.
See also "PL_sv_yes" and "PL_sv_no".
SV * boolSV(bool b)
"croak_xs_usage"
A specialised variant of croak() for emitting the usage message for
xsubs
croak_xs_usage(cv, "eee_yow");
works out the package name and subroutine name from "cv", and then
calls croak(). Hence if "cv" is &ouch::awk, it would call "croak"
as:
diag_listed_as: SKIPME
Perl_croak(aTHX_ "Usage: %" SVf "::%" SVf "(%s)", "ouch" "awk",
"eee_yow");
void croak_xs_usage(const CV * const cv,
const char * const params)
"DEFSV"
Returns the SV associated with $_
SV * DEFSV
"DEFSV_set"
Associate "sv" with $_
void DEFSV_set(SV * sv)
"get_sv"
Returns the SV of the specified Perl scalar. "flags" are passed to
""gv_fetchpv"". If "GV_ADD" is set and the Perl variable does not
exist then it will be created. If "flags" is zero and the variable
does not exist then NULL is returned.
NOTE: the perl_get_sv() form is deprecated.
SV * get_sv(const char *name, I32 flags)
"isGV_with_GP"
Returns a boolean as to whether or not "sv" is a GV with a pointer
to a GP (glob pointer).
bool isGV_with_GP(SV * sv)
"looks_like_number"
Test if the content of an SV looks like a number (or is a number).
"Inf" and "Infinity" are treated as numbers (so will not issue a
non-numeric warning), even if your atof() doesn't grok them. Get-
magic is ignored.
I32 looks_like_number(SV * const sv)
"MUTABLE_AV"
"MUTABLE_CV"
"MUTABLE_GV"
"MUTABLE_HV"
"MUTABLE_IO"
"MUTABLE_PTR"
"MUTABLE_SV"
The "MUTABLE_*"() macros cast pointers to the types shown, in such a
way (compiler permitting) that casting away const-ness will give a
warning; e.g.:
const SV *sv = ...;
AV *av1 = (AV*)sv; <== BAD: the const has been silently
cast away
AV *av2 = MUTABLE_AV(sv); <== GOOD: it may warn
"MUTABLE_PTR" is the base macro used to derive new casts. The other
already-built-in ones return pointers to what their names indicate.
AV * MUTABLE_AV (AV * p)
CV * MUTABLE_CV (CV * p)
GV * MUTABLE_GV (GV * p)
HV * MUTABLE_HV (HV * p)
IO * MUTABLE_IO (IO * p)
void * MUTABLE_PTR(void * p)
SV * MUTABLE_SV (SV * p)
"newRV"
"newRV_inc"
These are identical. They create an RV wrapper for an SV. The
reference count for the original SV is incremented.
SV * newRV(SV * const sv)
"newRV_noinc"
Creates an RV wrapper for an SV. The reference count for the
original SV is not incremented.
SV * newRV_noinc(SV * const tmpRef)
"newSV"
Creates a new SV. A non-zero "len" parameter indicates the number
of bytes of preallocated string space the SV should have. An extra
byte for a trailing "NUL" is also reserved. ("SvPOK" is not set for
the SV even if string space is allocated.) The reference count for
the new SV is set to 1.
In 5.9.3, newSV() replaces the older NEWSV() API, and drops the
first parameter, x, a debug aid which allowed callers to identify
themselves. This aid has been superseded by a new build option,
"PERL_MEM_LOG" (see "PERL_MEM_LOG" in perlhacktips). The older API
is still there for use in XS modules supporting older perls.
SV * newSV(const STRLEN len)
"newSVbool"
Creates a new SV boolean.
SV * newSVbool(const bool bool_val)
"newSV_false"
Creates a new SV that is a boolean false.
SV * newSV_false()
"newSVhek"
Creates a new SV from the hash key structure. It will generate
scalars that point to the shared string table where possible.
Returns a new (undefined) SV if "hek" is NULL.
SV * newSVhek(const HEK * const hek)
"newSVhek_mortal"
Creates a new mortal SV from the hash key structure. It will
generate scalars that point to the shared string table where
possible. Returns a new (undefined) SV if "hek" is NULL.
This is more efficient than using sv_2mortal(newSVhek( ... ))
SV * newSVhek_mortal(const HEK * const hek)
"newSViv"
Creates a new SV and copies an integer into it. The reference count
for the SV is set to 1.
SV * newSViv(const IV i)
"newSVnv"
Creates a new SV and copies a floating point value into it. The
reference count for the SV is set to 1.
SV * newSVnv(const NV n)
"newSVpadname"
NOTE: "newSVpadname" is experimental and may change or be removed
without notice.
Creates a new SV containing the pad name.
SV* newSVpadname(PADNAME *pn)
"newSVpv"
Creates a new SV and copies a string (which may contain "NUL" ("\0")
characters) into it. The reference count for the SV is set to 1.
If "len" is zero, Perl will compute the length using strlen(),
(which means if you use this option, that "s" can't have embedded
"NUL" characters and has to have a terminating "NUL" byte).
This function can cause reliability issues if you are likely to pass
in empty strings that are not null terminated, because it will run
strlen on the string and potentially run past valid memory.
Using "newSVpvn" is a safer alternative for non "NUL" terminated
strings. For string literals use "newSVpvs" instead. This function
will work fine for "NUL" terminated strings, but if you want to
avoid the if statement on whether to call "strlen" use "newSVpvn"
instead (calling "strlen" yourself).
SV * newSVpv(const char * const s, const STRLEN len)
"newSVpvf"
Creates a new SV and initializes it with the string formatted like
"sv_catpvf".
NOTE: "newSVpvf" must be explicitly called as "Perl_newSVpvf" with
an "aTHX_" parameter.
SV * Perl_newSVpvf(pTHX_ const char * const pat, ...)
"newSVpvf_nocontext"
Like "newSVpvf" but does not take a thread context ("aTHX")
parameter, so is used in situations where the caller doesn't already
have the thread context.
SV * newSVpvf_nocontext(const char * const pat, ...)
"newSVpvn"
Creates a new SV and copies a string into it, which may contain
"NUL" characters ("\0") and other binary data. The reference count
for the SV is set to 1. Note that if "len" is zero, Perl will
create a zero length (Perl) string. You are responsible for
ensuring that the source buffer is at least "len" bytes long. If
the "buffer" argument is NULL the new SV will be undefined.
SV * newSVpvn(const char * const buffer, const STRLEN len)
"newSVpvn_flags"
Creates a new SV and copies a string (which may contain "NUL" ("\0")
characters) into it. The reference count for the SV is set to 1.
Note that if "len" is zero, Perl will create a zero length string.
You are responsible for ensuring that the source string is at least
"len" bytes long. If the "s" argument is NULL the new SV will be
undefined. Currently the only flag bits accepted are "SVf_UTF8" and
"SVs_TEMP". If "SVs_TEMP" is set, then sv_2mortal() is called on
the result before returning. If "SVf_UTF8" is set, "s" is
considered to be in UTF-8 and the "SVf_UTF8" flag will be set on the
new SV. newSVpvn_utf8() is a convenience wrapper for this function,
defined as
#define newSVpvn_utf8(s, len, u) \
newSVpvn_flags((s), (len), (u) ? SVf_UTF8 : 0)
SV * newSVpvn_flags(const char * const s, const STRLEN len,
const U32 flags)
"newSVpvn_share"
Creates a new SV with its "SvPVX_const" pointing to a shared string
in the string table. If the string does not already exist in the
table, it is created first. Turns on the "SvIsCOW" flag (or
"READONLY" and "FAKE" in 5.16 and earlier). If the "hash" parameter
is non-zero, that value is used; otherwise the hash is computed.
The string's hash can later be retrieved from the SV with the
"SvSHARED_HASH" macro. The idea here is that as the string table is
used for shared hash keys these strings will have "SvPVX_const ==
HeKEY" and hash lookup will avoid string compare.
SV * newSVpvn_share(const char *s, I32 len, U32 hash)
"newSVpvn_utf8"
Creates a new SV and copies a string (which may contain "NUL" ("\0")
characters) into it. If "utf8" is true, calls "SvUTF8_on" on the
new SV. Implemented as a wrapper around "newSVpvn_flags".
SV* newSVpvn_utf8(const char* s, STRLEN len, U32 utf8)
"newSVpvs"
Like "newSVpvn", but takes a literal string instead of a
string/length pair.
SV* newSVpvs("literal string")
"newSVpvs_flags"
Like "newSVpvn_flags", but takes a literal string instead of a
string/length pair.
SV* newSVpvs_flags("literal string", U32 flags)
"newSVpv_share"
Like "newSVpvn_share", but takes a "NUL"-terminated string instead
of a string/length pair.
SV * newSVpv_share(const char *s, U32 hash)
"newSVpvs_share"
Like "newSVpvn_share", but takes a literal string instead of a
string/length pair and omits the hash parameter.
SV* newSVpvs_share("literal string")
"newSVrv"
Creates a new SV for the existing RV, "rv", to point to. If "rv" is
not an RV then it will be upgraded to one. If "classname" is non-
null then the new SV will be blessed in the specified package. The
new SV is returned and its reference count is 1. The reference
count 1 is owned by "rv". See also newRV_inc() and newRV_noinc() for
creating a new RV properly.
SV * newSVrv(SV * const rv, const char * const classname)
"newSVsv"
"newSVsv_flags"
"newSVsv_nomg"
These create a new SV which is an exact duplicate of the original SV
(using "sv_setsv".)
They differ only in that "newSVsv" performs 'get' magic;
"newSVsv_nomg" skips any magic; and "newSVsv_flags" allows you to
explicitly set a "flags" parameter.
SV * newSVsv (SV * const old)
SV * newSVsv_flags(SV * const old, I32 flags)
SV * newSVsv_nomg (SV * const old)
"newSV_true"
Creates a new SV that is a boolean true.
SV * newSV_true()
"newSV_type"
Creates a new SV, of the type specified. The reference count for
the new SV is set to 1.
SV * newSV_type(const svtype type)
"newSV_type_mortal"
Creates a new mortal SV, of the type specified. The reference count
for the new SV is set to 1.
This is equivalent to
SV* sv = sv_2mortal(newSV_type(<some type>)) and
SV* sv = sv_newmortal();
sv_upgrade(sv, <some_type>) but should be more efficient than
both of them. (Unless sv_2mortal is inlined at some point in the
future.)
SV * newSV_type_mortal(const svtype type)
"newSVuv"
Creates a new SV and copies an unsigned integer into it. The
reference count for the SV is set to 1.
SV * newSVuv(const UV u)
"Nullsv"
Null SV pointer. (No longer available when "PERL_CORE" is defined.)
"PL_sv_no"
This is the "false" SV. It is readonly. See "PL_sv_yes". Always
refer to this as &PL_sv_no.
SV PL_sv_no
"PL_sv_undef"
This is the "undef" SV. It is readonly. Always refer to this as
&PL_sv_undef.
SV PL_sv_undef
"PL_sv_yes"
This is the "true" SV. It is readonly. See "PL_sv_no". Always
refer to this as &PL_sv_yes.
SV PL_sv_yes
"PL_sv_zero"
This readonly SV has a zero numeric value and a "0" string value.
It's similar to "PL_sv_no" except for its string value. Can be used
as a cheap alternative to mXPUSHi(0) for example. Always refer to
this as &PL_sv_zero. Introduced in 5.28.
SV PL_sv_zero
"SAVE_DEFSV"
Localize $_. See "Localizing changes" in perlguts.
void SAVE_DEFSV
"sortsv"
In-place sort an array of SV pointers with the given comparison
routine.
Currently this always uses mergesort. See "sortsv_flags" for a more
flexible routine.
void sortsv(SV **array, size_t num_elts, SVCOMPARE_t cmp)
"sortsv_flags"
In-place sort an array of SV pointers with the given comparison
routine, with various SORTf_* flag options.
void sortsv_flags(SV **array, size_t num_elts, SVCOMPARE_t cmp,
U32 flags)
"SV"
Described in perlguts.
"SvAMAGIC"
Returns a boolean as to whether "sv" has overloading (active magic)
enabled or not.
bool SvAMAGIC(SV * sv)
"SvAMAGIC_off"
Indicate that "sv" has overloading (active magic) disabled.
void SvAMAGIC_off(SV *sv)
"SvAMAGIC_on"
Indicate that "sv" has overloading (active magic) enabled.
void SvAMAGIC_on(SV *sv)
"sv_backoff"
Remove any string offset. You should normally use the "SvOOK_off"
macro wrapper instead.
void sv_backoff(SV * const sv)
"sv_bless"
Blesses an SV into a specified package. The SV must be an RV. The
package must be designated by its stash (see "gv_stashpv"). The
reference count of the SV is unaffected.
SV * sv_bless(SV * const sv, HV * const stash)
"SvBoolFlagsOK"
Returns a bool indicating whether the SV has the right flags set
such that it is safe to call BOOL_INTERNALS_sv_isbool() or
BOOL_INTERNALS_sv_isbool_true() or BOOL_INTERNALS_sv_isbool_false().
Currently equivalent to SvIandPOK(sv) or "SvIOK(sv) && SvPOK(sv)".
Serialization may want to unroll this check. If so you are strongly
recommended to add code like "assert(SvBoolFlagsOK(sv));" before
calling using any of the BOOL_INTERNALS macros.
U32 SvBoolFlagsOK(SV* sv)
"sv_catpv"
"sv_catpv_flags"
"sv_catpv_mg"
"sv_catpv_nomg"
These concatenate the "NUL"-terminated string "sstr" onto the end of
the string which is in the SV. If the SV has the UTF-8 status set,
then the bytes appended should be valid UTF-8.
They differ only in how they handle magic:
"sv_catpv_mg" performs both 'get' and 'set' magic.
"sv_catpv" performs only 'get' magic.
"sv_catpv_nomg" skips all magic.
"sv_catpv_flags" has an extra "flags" parameter which allows you to
specify any combination of magic handling (using "SV_GMAGIC" and/or
"SV_SMAGIC"), and to also override the UTF-8 handling. By supplying
the "SV_CATUTF8" flag, the appended string is forced to be
interpreted as UTF-8; by supplying instead the "SV_CATBYTES" flag,
it will be interpreted as just bytes. Either the SV or the string
appended will be upgraded to UTF-8 if necessary.
void sv_catpv (SV * const dsv, const char *sstr)
void sv_catpv_flags(SV *dsv, const char *sstr, const I32 flags)
void sv_catpv_mg (SV * const dsv, const char * const sstr)
void sv_catpv_nomg (SV * const dsv, const char *sstr)
"sv_catpvf"
"sv_catpvf_mg"
"sv_catpvf_mg_nocontext"
"sv_catpvf_nocontext"
These process their arguments like "sprintf", and append the
formatted output to an SV. As with "sv_vcatpvfn", argument
reordering is not supporte when called with a non-null C-style
variable argument list.
If the appended data contains "wide" characters (including, but not
limited to, SVs with a UTF-8 PV formatted with %s, and characters
>255 formatted with %c), the original SV might get upgraded to
UTF-8.
If the original SV was UTF-8, the pattern should be valid UTF-8; if
the original SV was bytes, the pattern should be too.
All perform 'get' magic, but only "sv_catpvf_mg" and
"sv_catpvf_mg_nocontext" perform 'set' magic.
"sv_catpvf_nocontext" and "sv_catpvf_mg_nocontext" do not take a
thread context ("aTHX") parameter, so are used in situations where
the caller doesn't already have the thread context.
NOTE: "sv_catpvf" must be explicitly called as "Perl_sv_catpvf" with
an "aTHX_" parameter.
NOTE: "sv_catpvf_mg" must be explicitly called as
"Perl_sv_catpvf_mg" with an "aTHX_" parameter.
void Perl_sv_catpvf (pTHX_ SV * const sv,
const char * const pat, ...)
void Perl_sv_catpvf_mg (pTHX_ SV * const sv,
const char * const pat, ...)
void sv_catpvf_mg_nocontext(SV * const sv,
const char * const pat, ...)
void sv_catpvf_nocontext (SV * const sv,
const char * const pat, ...)
"sv_catpvn"
"sv_catpvn_flags"
"sv_catpvn_mg"
"sv_catpvn_nomg"
These concatenate the "len" bytes of the string beginning at "ptr"
onto the end of the string which is in "dsv". The caller must make
sure "ptr" contains at least "len" bytes.
For all but "sv_catpvn_flags", the string appended is assumed to be
valid UTF-8 if the SV has the UTF-8 status set, and a string of
bytes otherwise.
They differ in that:
"sv_catpvn_mg" performs both 'get' and 'set' magic on "dsv".
"sv_catpvn" performs only 'get' magic.
"sv_catpvn_nomg" skips all magic.
"sv_catpvn_flags" has an extra "flags" parameter which allows you to
specify any combination of magic handling (using "SV_GMAGIC" and/or
"SV_SMAGIC") and to also override the UTF-8 handling. By supplying
the "SV_CATBYTES" flag, the appended string is interpreted as plain
bytes; by supplying instead the "SV_CATUTF8" flag, it will be
interpreted as UTF-8, and the "dsv" will be upgraded to UTF-8 if
necessary.
"sv_catpvn", "sv_catpvn_mg", and "sv_catpvn_nomg" are implemented in
terms of "sv_catpvn_flags".
void sv_catpvn (SV *dsv, const char *sstr, STRLEN len)
void sv_catpvn_flags(SV * const dsv, const char *sstr,
const STRLEN len, const I32 flags)
void sv_catpvn_mg (SV *dsv, const char *sstr, STRLEN len)
void sv_catpvn_nomg (SV *dsv, const char *sstr, STRLEN len)
"sv_catpvs"
Like "sv_catpvn", but takes a literal string instead of a
string/length pair.
void sv_catpvs(SV* sv, "literal string")
"sv_catpvs_flags"
Like "sv_catpvn_flags", but takes a literal string instead of a
string/length pair.
void sv_catpvs_flags(SV* sv, "literal string", I32 flags)
"sv_catpvs_mg"
Like "sv_catpvn_mg", but takes a literal string instead of a
string/length pair.
void sv_catpvs_mg(SV* sv, "literal string")
"sv_catpvs_nomg"
Like "sv_catpvn_nomg", but takes a literal string instead of a
string/length pair.
void sv_catpvs_nomg(SV* sv, "literal string")
"sv_catsv"
"sv_catsv_flags"
"sv_catsv_mg"
"sv_catsv_nomg"
These concatenate the string from SV "sstr" onto the end of the
string in SV "dsv". If "sstr" is null, these are no-ops; otherwise
only "dsv" is modified.
They differ only in what magic they perform:
"sv_catsv_mg" performs 'get' magic on both SVs before the copy, and
'set' magic on "dsv" afterwards.
"sv_catsv" performs just 'get' magic, on both SVs.
"sv_catsv_nomg" skips all magic.
"sv_catsv_flags" has an extra "flags" parameter which allows you to
use "SV_GMAGIC" and/or "SV_SMAGIC" to specify any combination of
magic handling (although either both or neither SV will have 'get'
magic applied to it.)
"sv_catsv", "sv_catsv_mg", and "sv_catsv_nomg" are implemented in
terms of "sv_catsv_flags".
void sv_catsv (SV *dsv, SV *sstr)
void sv_catsv_flags(SV * const dsv, SV * const sstr,
const I32 flags)
void sv_catsv_mg (SV *dsv, SV *sstr)
void sv_catsv_nomg (SV *dsv, SV *sstr)
"SV_CHECK_THINKFIRST"
Remove any encumbrances from "sv", that need to be taken care of
before it is modifiable. For example if it is Copy on Write (COW),
now is the time to make that copy.
If you know that you are about to change the PV value of "sv",
instead use ""SV_CHECK_THINKFIRST_COW_DROP"" to avoid the write that
would be immediately written again.
void SV_CHECK_THINKFIRST(SV * sv)
"SV_CHECK_THINKFIRST_COW_DROP"
Call this when you are about to replace the PV value in "sv", which
is potentially copy-on-write. It stops any sharing with other SVs,
so that no Copy on Write (COW) actually happens. This COW would be
useless, as it would immediately get changed to something else.
This function also removes any other encumbrances that would be
problematic when changing "sv".
void SV_CHECK_THINKFIRST_COW_DROP(SV * sv)
"sv_chop"
Efficient removal of characters from the beginning of the string
buffer. SvPOK(sv), or at least SvPOKp(sv), must be true and "ptr"
must be a pointer to somewhere inside the string buffer. "ptr"
becomes the first character of the adjusted string. Uses the "OOK"
hack. On return, only SvPOK(sv) and SvPOKp(sv) among the "OK" flags
will be true.
Beware: after this function returns, "ptr" and SvPVX_const(sv) may
no longer refer to the same chunk of data.
The unfortunate similarity of this function's name to that of Perl's
"chop" operator is strictly coincidental. This function works from
the left; "chop" works from the right.
void sv_chop(SV * const sv, const char * const ptr)
"sv_clear"
Clear an SV: call any destructors, free up any memory used by the
body, and free the body itself. The SV's head is not freed,
although its type is set to all 1's so that it won't inadvertently
be assumed to be live during global destruction etc. This function
should only be called when "REFCNT" is zero. Most of the time
you'll want to call "SvREFCNT_dec" instead.
void sv_clear(SV * const orig_sv)
"sv_cmp"
Compares the strings in two SVs. Returns -1, 0, or 1 indicating
whether the string in "sv1" is less than, equal to, or greater than
the string in "sv2". Is UTF-8 and 'use bytes' aware, handles get
magic, and will coerce its args to strings if necessary. See also
"sv_cmp_locale".
I32 sv_cmp(SV * const sv1, SV * const sv2)
"sv_cmp_flags"
Compares the strings in two SVs. Returns -1, 0, or 1 indicating
whether the string in "sv1" is less than, equal to, or greater than
the string in "sv2". Is UTF-8 and 'use bytes' aware and will coerce
its args to strings if necessary. If the flags has the "SV_GMAGIC"
bit set, it handles get magic. See also "sv_cmp_locale_flags".
I32 sv_cmp_flags(SV * const sv1, SV * const sv2, const U32 flags)
"sv_cmp_locale"
Compares the strings in two SVs in a locale-aware manner. Is UTF-8
and 'use bytes' aware, handles get magic, and will coerce its args
to strings if necessary. See also "sv_cmp".
I32 sv_cmp_locale(SV * const sv1, SV * const sv2)
"sv_cmp_locale_flags"
Compares the strings in two SVs in a locale-aware manner. Is UTF-8
and 'use bytes' aware and will coerce its args to strings if
necessary. If the flags contain "SV_GMAGIC", it handles get magic.
See also "sv_cmp_flags".
I32 sv_cmp_locale_flags(SV * const sv1, SV * const sv2,
const U32 flags)
"sv_collxfrm"
This calls "sv_collxfrm_flags" with the SV_GMAGIC flag. See
"sv_collxfrm_flags".
char * sv_collxfrm(SV * const sv, STRLEN * const nxp)
"sv_collxfrm_flags"
Add Collate Transform magic to an SV if it doesn't already have it.
If the flags contain "SV_GMAGIC", it handles get-magic.
Any scalar variable may carry "PERL_MAGIC_collxfrm" magic that
contains the scalar data of the variable, but transformed to such a
format that a normal memory comparison can be used to compare the
data according to the locale settings.
char * sv_collxfrm_flags(SV * const sv, STRLEN * const nxp,
I32 const flags)
"sv_copypv"
"sv_copypv_flags"
"sv_copypv_nomg"
These copy a stringified representation of the source SV into the
destination SV. They automatically perform coercion of numeric
values into strings. Guaranteed to preserve the "UTF8" flag even
from overloaded objects. Similar in nature to "sv_2pv[_flags]" but
they operate directly on an SV instead of just the string. Mostly
they use ""sv_2pv_flags"" to do the work, except when that would
lose the UTF-8'ness of the PV.
The three forms differ only in whether or not they perform 'get
magic' on "sv". "sv_copypv_nomg" skips 'get magic'; "sv_copypv"
performs it; and "sv_copypv_flags" either performs it (if the
"SV_GMAGIC" bit is set in "flags") or doesn't (if that bit is
cleared).
void sv_copypv (SV * const dsv, SV * const ssv)
void sv_copypv_flags(SV * const dsv, SV * const ssv,
const I32 flags)
void sv_copypv_nomg (SV * const dsv, SV * const ssv)
"SvCUR"
Returns the length, in bytes, of the PV inside the SV. Note that
this may not match Perl's "length"; for that, use sv_len_utf8(sv).
See "SvLEN" also.
STRLEN SvCUR(SV* sv)
"SvCUR_set"
Sets the current length, in bytes, of the C string which is in the
SV. See "SvCUR" and "SvIV_set">.
void SvCUR_set(SV* sv, STRLEN len)
"sv_2cv"
Using various gambits, try to get a CV from an SV; in addition, try
if possible to set *st and *gvp to the stash and GV associated with
it. The flags in "lref" are passed to "gv_fetchsv".
CV * sv_2cv(SV *sv, HV ** const st, GV ** const gvp,
const I32 lref)
"sv_dec"
"sv_dec_nomg"
These auto-decrement the value in the SV, doing string to numeric
conversion if necessary. They both handle operator overloading.
They differ only in that:
"sv_dec" handles 'get' magic; "sv_dec_nomg" skips 'get' magic.
void sv_dec(SV * const sv)
"sv_derived_from"
Exactly like "sv_derived_from_pv", but doesn't take a "flags"
parameter.
bool sv_derived_from(SV *sv, const char * const name)
"sv_derived_from_hv"
Exactly like "sv_derived_from_pvn", but takes the name string as the
"HvNAME" of the given HV (which would presumably represent a stash).
bool sv_derived_from_hv(SV *sv, HV *hv)
"sv_derived_from_pv"
Exactly like "sv_derived_from_pvn", but takes a nul-terminated
string instead of a string/length pair.
bool sv_derived_from_pv(SV *sv, const char * const name,
U32 flags)
"sv_derived_from_pvn"
Returns a boolean indicating whether the SV is derived from the
specified class at the C level. To check derivation at the Perl
level, call isa() as a normal Perl method.
Currently, the only significant value for "flags" is SVf_UTF8.
bool sv_derived_from_pvn(SV *sv, const char * const name,
const STRLEN len, U32 flags)
"sv_derived_from_sv"
Exactly like "sv_derived_from_pvn", but takes the name string in the
form of an SV instead of a string/length pair. This is the advised
form.
bool sv_derived_from_sv(SV *sv, SV *namesv, U32 flags)
"sv_does"
Like "sv_does_pv", but doesn't take a "flags" parameter.
bool sv_does(SV *sv, const char * const name)
"sv_does_pv"
Like "sv_does_sv", but takes a nul-terminated string instead of an
SV.
bool sv_does_pv(SV *sv, const char * const name, U32 flags)
"sv_does_pvn"
Like "sv_does_sv", but takes a string/length pair instead of an SV.
bool sv_does_pvn(SV *sv, const char * const name,
const STRLEN len, U32 flags)
"sv_does_sv"
Returns a boolean indicating whether the SV performs a specific,
named role. The SV can be a Perl object or the name of a Perl
class.
bool sv_does_sv(SV *sv, SV *namesv, U32 flags)
"SvEND"
Returns a pointer to the spot just after the last character in the
string which is in the SV, where there is usually a trailing "NUL"
character (even though Perl scalars do not strictly require it).
See "SvCUR". Access the character as "*(SvEND(sv))".
Warning: If "SvCUR" is equal to "SvLEN", then "SvEND" points to
unallocated memory.
char* SvEND(SV* sv)
"sv_eq"
"sv_eq_flags"
These each return a boolean indicating whether or not the strings in
the two SVs are equal. If 'use bytes' is in effect, the comparison
is byte-by-byte; otherwise character-by-character. Each will coerce
its args to strings if necessary.
They differ only in that "sv_eq" always processes get magic, while
"sv_eq_flags" processes get magic only when the "flags" parameter
has the "SV_GMAGIC" bit set.
These functions do not handle operator overloading. For versions
that do, see instead "sv_streq" or "sv_streq_flags".
I32 sv_eq (SV *sv1, SV *sv2)
I32 sv_eq_flags(SV *sv1, SV *sv2, const U32 flags)
"sv_force_normal"
Undo various types of fakery on an SV: if the PV is a shared string,
make a private copy; if we're a ref, stop refing; if we're a glob,
downgrade to an "xpvmg". See also "sv_force_normal_flags".
void sv_force_normal(SV *sv)
"sv_force_normal_flags"
Undo various types of fakery on an SV, where fakery means "more
than" a string: if the PV is a shared string, make a private copy;
if we're a ref, stop refing; if we're a glob, downgrade to an
"xpvmg"; if we're a copy-on-write scalar, this is the on-write time
when we do the copy, and is also used locally; if this is a vstring,
drop the vstring magic. If "SV_COW_DROP_PV" is set then a copy-on-
write scalar drops its PV buffer (if any) and becomes "SvPOK_off"
rather than making a copy. (Used where this scalar is about to be
set to some other value.) In addition, the "flags" parameter gets
passed to sv_unref_flags() when unreffing. "sv_force_normal" calls
this function with flags set to 0.
This function is expected to be used to signal to perl that this SV
is about to be written to, and any extra book-keeping needs to be
taken care of. Hence, it croaks on read-only values.
void sv_force_normal_flags(SV * const sv, const U32 flags)
"sv_free"
Decrement an SV's reference count, and if it drops to zero, call
"sv_clear" to invoke destructors and free up any memory used by the
body; finally, deallocating the SV's head itself. Normally called
via a wrapper macro "SvREFCNT_dec".
void sv_free(SV * const sv)
"SvGAMAGIC"
Returns true if the SV has get magic or overloading. If either is
true then the scalar is active data, and has the potential to return
a new value every time it is accessed. Hence you must be careful to
only read it once per user logical operation and work with that
returned value. If neither is true then the scalar's value cannot
change unless written to.
U32 SvGAMAGIC(SV* sv)
"sv_get_backrefs"
NOTE: "sv_get_backrefs" is experimental and may change or be removed
without notice.
If "sv" is the target of a weak reference then it returns the back
references structure associated with the sv; otherwise return
"NULL".
When returning a non-null result the type of the return is relevant.
If it is an AV then the elements of the AV are the weak reference
RVs which point at this item. If it is any other type then the item
itself is the weak reference.
See also Perl_sv_add_backref(), Perl_sv_del_backref(),
Perl_sv_kill_backrefs()
SV * sv_get_backrefs(SV * const sv)
"SvGETMAGIC"
Invokes "mg_get" on an SV if it has 'get' magic. For example, this
will call "FETCH" on a tied variable. As of 5.37.1, this function
is guaranteed to evaluate its argument exactly once.
void SvGETMAGIC(SV *sv)
"sv_gets"
Get a line from the filehandle and store it into the SV, optionally
appending to the currently-stored string. If "append" is not 0, the
line is appended to the SV instead of overwriting it. "append"
should be set to the byte offset that the appended string should
start at in the SV (typically, SvCUR(sv) is a suitable choice).
char * sv_gets(SV * const sv, PerlIO * const fp, I32 append)
"SvGROW"
Expands the character buffer in the SV so that it has room for the
indicated number of bytes (remember to reserve space for an extra
trailing "NUL" character). Calls "sv_grow" to perform the expansion
if necessary. Returns a pointer to the character buffer. SV must
be of type >= "SVt_PV". One alternative is to call "sv_grow" if you
are not sure of the type of SV.
You might mistakenly think that "len" is the number of bytes to add
to the existing size, but instead it is the total size "sv" should
be.
char * SvGROW(SV* sv, STRLEN len)
"SvIandPOK"
Returns a bool indicating whether the SV is both SvPOK() and SvIOK()
at the same time. Equivalent to "SvIOK(sv) && SvPOK(sv)" but more
efficient.
U32 SvIandPOK(SV* sv)
"SvIandPOK_off"
Unsets the PV and IV status of an SV in one operation. Equivalent to
"SvIOK_off(sv); SvPK_off(v);" but more efficient.
void SvIandPOK_off(SV* sv)
"SvIandPOK_on"
Tells an SV that is a string and a number in one operation.
Equivalent to "SvIOK_on(sv); SvPOK_on(sv);" but more efficient.
void SvIandPOK_on(SV* sv)
"sv_inc"
"sv_inc_nomg"
These auto-increment the value in the SV, doing string to numeric
conversion if necessary. They both handle operator overloading.
They differ only in that "sv_inc" performs 'get' magic;
"sv_inc_nomg" skips any magic.
void sv_inc(SV * const sv)
"sv_insert"
"sv_insert_flags"
These insert and/or replace a string at the specified offset/length
within the SV. Similar to the Perl substr() function, with
"littlelen" bytes starting at "little" replacing "len" bytes of the
string in "bigstr" starting at "offset". They handle get magic.
"sv_insert_flags" is identical to plain "sv_insert", but the extra
"flags" are passed to the "SvPV_force_flags" operation that is
internally applied to "bigstr".
void sv_insert (SV * const bigstr, const STRLEN offset,
const STRLEN len, const char * const little,
const STRLEN littlelen)
void sv_insert_flags(SV * const bigstr, const STRLEN offset,
const STRLEN len, const char *little,
const STRLEN littlelen, const U32 flags)
"sv_2io"
Using various gambits, try to get an IO from an SV: the IO slot if
its a GV; or the recursive result if we're an RV; or the IO slot of
the symbol named after the PV if we're a string.
'Get' magic is ignored on the "sv" passed in, but will be called on
SvRV(sv) if "sv" is an RV.
IO * sv_2io(SV * const sv)
"SvIOK"
Returns a U32 value indicating whether the SV contains an integer.
U32 SvIOK(SV* sv)
"SvIOK_notUV"
Returns a boolean indicating whether the SV contains a signed
integer.
bool SvIOK_notUV(SV* sv)
"SvIOK_off"
Unsets the IV status of an SV.
void SvIOK_off(SV* sv)
"SvIOK_on"
Tells an SV that it is an integer.
void SvIOK_on(SV* sv)
"SvIOK_only"
Tells an SV that it is an integer and disables all other "OK" bits.
void SvIOK_only(SV* sv)
"SvIOK_only_UV"
Tells an SV that it is an unsigned integer and disables all other
"OK" bits.
void SvIOK_only_UV(SV* sv)
"SvIOKp"
Returns a U32 value indicating whether the SV contains an integer.
Checks the private setting. Use "SvIOK" instead.
U32 SvIOKp(SV* sv)
"SvIOK_UV"
Returns a boolean indicating whether the SV contains an integer that
must be interpreted as unsigned. A non-negative integer whose value
is within the range of both an IV and a UV may be flagged as either
"SvUOK" or "SvIOK".
bool SvIOK_UV(SV* sv)
"sv_isa"
Returns a boolean indicating whether the SV is blessed into the
specified class.
This does not check for subtypes or method overloading. Use
"sv_isa_sv" to verify an inheritance relationship in the same way as
the "isa" operator by respecting any isa() method overloading; or
"sv_derived_from_sv" to test directly on the actual object type.
int sv_isa(SV *sv, const char * const name)
"sv_isa_sv"
Returns a boolean indicating whether the SV is an object reference
and is derived from the specified class, respecting any isa() method
overloading it may have. Returns false if "sv" is not a reference to
an object, or is not derived from the specified class.
This is the function used to implement the behaviour of the "isa"
operator.
Does not invoke magic on "sv".
Not to be confused with the older "sv_isa" function, which does not
use an overloaded isa() method, nor will check subclassing.
bool sv_isa_sv(SV *sv, SV *namesv)
"SvIsBOOL"
Returns true if the SV is one of the special boolean constants
(PL_sv_yes or PL_sv_no), or is a regular SV whose last assignment
stored a copy of one.
bool SvIsBOOL(SV* sv)
"SvIsCOW"
Returns a U32 value indicating whether the SV is Copy-On-Write
(either shared hash key scalars, or full Copy On Write scalars if
5.9.0 is configured for COW).
U32 SvIsCOW(SV* sv)
"SvIsCOW_shared_hash"
Returns a boolean indicating whether the SV is Copy-On-Write shared
hash key scalar.
bool SvIsCOW_shared_hash(SV* sv)
"sv_isobject"
Returns a boolean indicating whether the SV is an RV pointing to a
blessed object. If the SV is not an RV, or if the object is not
blessed, then this will return false.
int sv_isobject(SV *sv)
"SvIV"
"SvIV_nomg"
"SvIVx"
These each coerce the given SV to IV and return it. The returned
value in many circumstances will get stored in "sv"'s IV slot, but
not in all cases. (Use "sv_setiv" to make sure it does).
As of 5.37.1, all are guaranteed to evaluate "sv" only once.
"SvIVx" is now identical to "SvIV", but prior to 5.37.1, it was the
only form guaranteed to evaluate "sv" only once.
"SvIV_nomg" is the same as "SvIV", but does not perform 'get' magic.
IV SvIV(SV *sv)
"sv_2iv_flags"
Return the integer value of an SV, doing any necessary string
conversion. If "flags" has the "SV_GMAGIC" bit set, does an
mg_get() first. Normally used via the SvIV(sv) and SvIVx(sv)
macros.
IV sv_2iv_flags(SV * const sv, const I32 flags)
"SvIV_set"
Set the value of the IV pointer in sv to val. It is possible to
perform the same function of this macro with an lvalue assignment to
"SvIVX". With future Perls, however, it will be more efficient to
use "SvIV_set" instead of the lvalue assignment to "SvIVX".
void SvIV_set(SV* sv, IV val)
"SvIVX"
Returns the raw value in the SV's IV slot, without checks or
conversions. Only use when you are sure "SvIOK" is true. See also
"SvIV".
IV SvIVX(SV* sv)
"SvLEN"
Returns the size of the string buffer in the SV, not including any
part attributable to "SvOOK". See "SvCUR".
STRLEN SvLEN(SV* sv)
"sv_len"
Returns the length of the string in the SV. Handles magic and type
coercion and sets the UTF8 flag appropriately. See also "SvCUR",
which gives raw access to the "xpv_cur" slot.
STRLEN sv_len(SV * const sv)
"SvLEN_set"
Set the size of the string buffer for the SV. See "SvLEN".
void SvLEN_set(SV* sv, STRLEN len)
"sv_len_utf8"
"sv_len_utf8_nomg"
These return the number of characters in the string in an SV,
counting wide UTF-8 bytes as a single character. Both handle type
coercion. They differ only in that "sv_len_utf8" performs 'get'
magic; "sv_len_utf8_nomg" skips any magic.
STRLEN sv_len_utf8(SV * const sv)
"SvLOCK"
Arranges for a mutual exclusion lock to be obtained on "sv" if a
suitable module has been loaded.
void SvLOCK(SV* sv)
"sv_magic"
Adds magic to an SV. First upgrades "sv" to type "SVt_PVMG" if
necessary, then adds a new magic item of type "how" to the head of
the magic list.
See "sv_magicext" (which "sv_magic" now calls) for a description of
the handling of the "name" and "namlen" arguments.
You need to use "sv_magicext" to add magic to "SvREADONLY" SVs and
also to add more than one instance of the same "how".
void sv_magic(SV * const sv, SV * const obj, const int how,
const char * const name, const I32 namlen)
"sv_magicext"
Adds magic to an SV, upgrading it if necessary. Applies the
supplied "vtable" and returns a pointer to the magic added.
Note that "sv_magicext" will allow things that "sv_magic" will not.
In particular, you can add magic to "SvREADONLY" SVs, and add more
than one instance of the same "how".
If "namlen" is greater than zero then a "savepvn" copy of "name" is
stored, if "namlen" is zero then "name" is stored as-is and - as
another special case - if "(name && namlen == HEf_SVKEY)" then
"name" is assumed to contain an SV* and is stored as-is with its
"REFCNT" incremented.
(This is now used as a subroutine by "sv_magic".)
MAGIC * sv_magicext(SV * const sv, SV * const obj, const int how,
const MGVTBL * const vtbl,
const char * const name, const I32 namlen)
"SvMAGIC_set"
Set the value of the MAGIC pointer in "sv" to val. See "SvIV_set".
void SvMAGIC_set(SV* sv, MAGIC* val)
"sv_2mortal"
Marks an existing SV as mortal. The SV will be destroyed "soon",
either by an explicit call to "FREETMPS", or by an implicit call at
places such as statement boundaries. SvTEMP() is turned on which
means that the SV's string buffer can be "stolen" if this SV is
copied. See also "sv_newmortal" and "sv_mortalcopy".
SV * sv_2mortal(SV * const sv)
"sv_mortalcopy"
Creates a new SV which is a copy of the original SV (using
"sv_setsv"). The new SV is marked as mortal. It will be destroyed
"soon", either by an explicit call to "FREETMPS", or by an implicit
call at places such as statement boundaries. See also
"sv_newmortal" and "sv_2mortal".
SV * sv_mortalcopy(SV * const oldsv)
"sv_mortalcopy_flags"
Like "sv_mortalcopy", but the extra "flags" are passed to the
"sv_setsv_flags".
SV * sv_mortalcopy_flags(SV * const oldsv, U32 flags)
"sv_newmortal"
Creates a new null SV which is mortal. The reference count of the
SV is set to 1. It will be destroyed "soon", either by an explicit
call to "FREETMPS", or by an implicit call at places such as
statement boundaries. See also "sv_mortalcopy" and "sv_2mortal".
SV * sv_newmortal()
"SvNIOK"
Returns a U32 value indicating whether the SV contains a number,
integer or double.
U32 SvNIOK(SV* sv)
"SvNIOK_off"
Unsets the NV/IV status of an SV.
void SvNIOK_off(SV* sv)
"SvNIOKp"
Returns a U32 value indicating whether the SV contains a number,
integer or double. Checks the private setting. Use "SvNIOK"
instead.
U32 SvNIOKp(SV* sv)
"SvNOK"
Returns a U32 value indicating whether the SV contains a double.
U32 SvNOK(SV* sv)
"SvNOK_off"
Unsets the NV status of an SV.
void SvNOK_off(SV* sv)
"SvNOK_on"
Tells an SV that it is a double.
void SvNOK_on(SV* sv)
"SvNOK_only"
Tells an SV that it is a double and disables all other OK bits.
void SvNOK_only(SV* sv)
"SvNOKp"
Returns a U32 value indicating whether the SV contains a double.
Checks the private setting. Use "SvNOK" instead.
U32 SvNOKp(SV* sv)
"sv_nolocking"
"DEPRECATED!" It is planned to remove "sv_nolocking" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Dummy routine which "locks" an SV when there is no locking module
present. Exists to avoid test for a "NULL" function pointer and
because it could potentially warn under some level of strict-ness.
"Superseded" by sv_nosharing().
void sv_nolocking(SV *sv)
"sv_nounlocking"
"DEPRECATED!" It is planned to remove "sv_nounlocking" from a
future release of Perl. Do not use it for new code; remove it from
existing code.
Dummy routine which "unlocks" an SV when there is no locking module
present. Exists to avoid test for a "NULL" function pointer and
because it could potentially warn under some level of strict-ness.
"Superseded" by sv_nosharing().
void sv_nounlocking(SV *sv)
"sv_numeq"
A convenient shortcut for calling "sv_numeq_flags" with the
"SV_GMAGIC" flag. This function basically behaves like the Perl code
"$sv1 == $sv2".
bool sv_numeq(SV *sv1, SV *sv2)
"sv_numeq_flags"
Returns a boolean indicating whether the numbers in the two SVs are
identical. If the flags argument has the "SV_GMAGIC" bit set, it
handles get-magic too. Will coerce its args to numbers if necessary.
Treats "NULL" as undef.
If flags does not have the "SV_SKIP_OVERLOAD" bit set, an attempt to
use "==" overloading will be made. If such overloading does not
exist or the flag is set, then regular numerical comparison will be
used instead.
bool sv_numeq_flags(SV *sv1, SV *sv2, const U32 flags)
"SvNV"
"SvNV_nomg"
"SvNVx"
These each coerce the given SV to NV and return it. The returned
value in many circumstances will get stored in "sv"'s NV slot, but
not in all cases. (Use "sv_setnv" to make sure it does).
As of 5.37.1, all are guaranteed to evaluate "sv" only once.
"SvNVx" is now identical to "SvNV", but prior to 5.37.1, it was the
only form guaranteed to evaluate "sv" only once.
"SvNV_nomg" is the same as "SvNV", but does not perform 'get' magic.
NV SvNV(SV *sv)
"sv_2nv_flags"
Return the num value of an SV, doing any necessary string or integer
conversion. If "flags" has the "SV_GMAGIC" bit set, does an
mg_get() first. Normally used via the SvNV(sv) and SvNVx(sv)
macros.
NV sv_2nv_flags(SV * const sv, const I32 flags)
"SvNV_set"
Set the value of the NV pointer in "sv" to val. See "SvIV_set".
void SvNV_set(SV* sv, NV val)
"SvNVX"
Returns the raw value in the SV's NV slot, without checks or
conversions. Only use when you are sure "SvNOK" is true. See also
"SvNV".
NV SvNVX(SV* sv)
"SvOK"
Returns a U32 value indicating whether the value is defined. This
is only meaningful for scalars.
U32 SvOK(SV* sv)
"SvOOK"
Returns a U32 indicating whether the pointer to the string buffer is
offset. This hack is used internally to speed up removal of
characters from the beginning of a "SvPV". When "SvOOK" is true,
then the start of the allocated string buffer is actually
SvOOK_offset() bytes before "SvPVX". This offset used to be stored
in "SvIVX", but is now stored within the spare part of the buffer.
U32 SvOOK(SV* sv)
"SvOOK_off"
Remove any string offset.
void SvOOK_off(SV * sv)
"SvOOK_offset"
Reads into "len" the offset from "SvPVX" back to the true start of
the allocated buffer, which will be non-zero if "sv_chop" has been
used to efficiently remove characters from start of the buffer.
Implemented as a macro, which takes the address of "len", which must
be of type "STRLEN". Evaluates "sv" more than once. Sets "len" to
0 if SvOOK(sv) is false.
void SvOOK_offset(SV*sv, STRLEN len)
"SvPOK"
Returns a U32 value indicating whether the SV contains a character
string.
U32 SvPOK(SV* sv)
"SvPOK_off"
Unsets the PV status of an SV.
void SvPOK_off(SV* sv)
"SvPOK_on"
Tells an SV that it is a string.
void SvPOK_on(SV* sv)
"SvPOK_only"
Tells an SV that it is a string and disables all other "OK" bits.
Will also turn off the UTF-8 status.
void SvPOK_only(SV* sv)
"SvPOK_only_UTF8"
Tells an SV that it is a string and disables all other "OK" bits,
and leaves the UTF-8 status as it was.
void SvPOK_only_UTF8(SV* sv)
"SvPOKp"
Returns a U32 value indicating whether the SV contains a character
string. Checks the private setting. Use "SvPOK" instead.
U32 SvPOKp(SV* sv)
"sv_pos_b2u"
Converts the value pointed to by "offsetp" from a count of bytes
from the start of the string, to a count of the equivalent number of
UTF-8 chars. Handles magic and type coercion.
Use "sv_pos_b2u_flags" in preference, which correctly handles
strings longer than 2Gb.
void sv_pos_b2u(SV * const sv, I32 * const offsetp)
"sv_pos_b2u_flags"
Converts "offset" from a count of bytes from the start of the
string, to a count of the equivalent number of UTF-8 chars. Handles
type coercion. "flags" is passed to "SvPV_flags", and usually
should be "SV_GMAGIC|SV_CONST_RETURN" to handle magic.
STRLEN sv_pos_b2u_flags(SV * const sv, STRLEN const offset,
U32 flags)
"sv_pos_u2b"
Converts the value pointed to by "offsetp" from a count of UTF-8
chars from the start of the string, to a count of the equivalent
number of bytes; if "lenp" is non-zero, it does the same to "lenp",
but this time starting from the offset, rather than from the start
of the string. Handles magic and type coercion.
Use "sv_pos_u2b_flags" in preference, which correctly handles
strings longer than 2Gb.
void sv_pos_u2b(SV * const sv, I32 * const offsetp,
I32 * const lenp)
"sv_pos_u2b_flags"
Converts the offset from a count of UTF-8 chars from the start of
the string, to a count of the equivalent number of bytes; if "lenp"
is non-zero, it does the same to "lenp", but this time starting from
"offset", rather than from the start of the string. Handles type
coercion. "flags" is passed to "SvPV_flags", and usually should be
"SV_GMAGIC|SV_CONST_RETURN" to handle magic.
STRLEN sv_pos_u2b_flags(SV * const sv, STRLEN uoffset,
STRLEN * const lenp, U32 flags)
"SvPV"
"SvPV_const"
"SvPV_flags"
"SvPV_flags_const"
"SvPV_flags_mutable"
"SvPV_mutable"
"SvPV_nolen"
"SvPV_nolen_const"
"SvPV_nomg"
"SvPV_nomg_const"
"SvPV_nomg_const_nolen"
"SvPV_nomg_nolen"
"SvPVbyte"
"SvPVbyte_nolen"
"SvPVbyte_nomg"
"SvPVbyte_or_null"
"SvPVbyte_or_null_nomg"
"SvPVbytex"
"SvPVbytex_nolen"
"SvPVutf8"
"SvPVutf8_nolen"
"SvPVutf8_nomg"
"SvPVutf8_or_null"
"SvPVutf8_or_null_nomg"
"SvPVutf8x"
"SvPVx"
"SvPVx_const"
"SvPVx_nolen"
"SvPVx_nolen_const"
These each return a pointer to the string in "sv", or a stringified
form of "sv" if it does not contain a string. The SV may cache the
stringified version becoming "SvPOK".
This is a very basic and common operation, so there are lots of
slightly different versions of it.
Note that there is no guarantee that the return value of SvPV(sv),
for example, is equal to SvPVX(sv), or that SvPVX(sv) contains valid
data, or that successive calls to SvPV(sv) (or another of these
forms) will return the same pointer value each time. This is due to
the way that things like overloading and Copy-On-Write are handled.
In these cases, the return value may point to a temporary buffer or
similar. If you absolutely need the "SvPVX" field to be valid (for
example, if you intend to write to it), then see "SvPV_force".
The differences between the forms are:
The forms with neither "byte" nor "utf8" in their names (e.g.,
"SvPV" or "SvPV_nolen") can expose the SV's internal string buffer.
If that buffer consists entirely of bytes 0-255 and includes any
bytes above 127, then you MUST consult "SvUTF8" to determine the
actual code points the string is meant to contain. Generally
speaking, it is probably safer to prefer "SvPVbyte", "SvPVutf8", and
the like. See "How do I pass a Perl string to a C library?" in
perlguts for more details.
The forms with "flags" in their names allow you to use the "flags"
parameter to specify to process 'get' magic (by setting the
"SV_GMAGIC" flag) or to skip 'get' magic (by clearing it). The
other forms process 'get' magic, except for the ones with "nomg" in
their names, which skip 'get' magic.
The forms that take a "len" parameter will set that variable to the
byte length of the resultant string (these are macros, so don't use
&len).
The forms with "nolen" in their names indicate they don't have a
"len" parameter. They should be used only when it is known that the
PV is a C string, terminated by a NUL byte, and without intermediate
NUL characters; or when you don't care about its length.
The forms with "const" in their names return "const char *" so that
the compiler will hopefully complain if you were to try to modify
the contents of the string (unless you cast away const yourself).
The other forms return a mutable pointer so that the string is
modifiable by the caller; this is emphasized for the ones with
"mutable" in their names.
As of 5.38, all forms are guaranteed to evaluate "sv" exactly once.
For earlier Perls, use a form whose name ends with "x" for single
evaluation.
"SvPVutf8" is like "SvPV", but converts "sv" to UTF-8 first if not
already UTF-8. Similarly, the other forms with "utf8" in their
names correspond to their respective forms without.
"SvPVutf8_or_null" and "SvPVutf8_or_null_nomg" don't have
corresponding non-"utf8" forms. Instead they are like
"SvPVutf8_nomg", but when "sv" is undef, they return "NULL".
"SvPVbyte" is like "SvPV", but converts "sv" to byte representation
first if currently encoded as UTF-8. If "sv" cannot be downgraded
from UTF-8, it croaks. Similarly, the other forms with "byte" in
their names correspond to their respective forms without.
"SvPVbyte_or_null" doesn't have a corresponding non-"byte" form.
Instead it is like "SvPVbyte", but when "sv" is undef, it returns
"NULL".
char* SvPV (SV* sv, STRLEN len)
const char* SvPV_const (SV* sv, STRLEN len)
char* SvPV_flags (SV* sv, STRLEN len, U32 flags)
const char* SvPV_flags_const (SV* sv, STRLEN len, U32 flags)
char* SvPV_flags_mutable (SV* sv, STRLEN len, U32 flags)
char* SvPV_mutable (SV* sv, STRLEN len)
char* SvPV_nolen (SV* sv)
const char* SvPV_nolen_const (SV* sv)
char* SvPV_nomg (SV* sv, STRLEN len)
const char* SvPV_nomg_const (SV* sv, STRLEN len)
const char* SvPV_nomg_const_nolen(SV* sv)
char* SvPV_nomg_nolen (SV* sv)
char* SvPVbyte (SV* sv, STRLEN len)
char* SvPVbyte_nolen (SV* sv)
char* SvPVbyte_nomg (SV* sv, STRLEN len)
char* SvPVbyte_or_null (SV* sv, STRLEN len)
char* SvPVbyte_or_null_nomg(SV* sv, STRLEN len)
char* SvPVbytex (SV* sv, STRLEN len)
char* SvPVbytex_nolen (SV* sv)
char* SvPVutf8 (SV* sv, STRLEN len)
char* SvPVutf8_nolen (SV* sv)
char* SvPVutf8_nomg (SV* sv, STRLEN len)
char* SvPVutf8_or_null (SV* sv, STRLEN len)
char* SvPVutf8_or_null_nomg(SV* sv, STRLEN len)
char* SvPVutf8x (SV* sv, STRLEN len)
char* SvPVx (SV* sv, STRLEN len)
const char* SvPVx_const (SV* sv, STRLEN len)
char* SvPVx_nolen (SV* sv)
const char* SvPVx_nolen_const (SV* sv)
"sv_2pv"
"sv_2pv_flags"
These implement the various forms of the ""SvPV"" in perlapi macros.
The macros are the preferred interface.
These return a pointer to the string value of an SV (coercing it to
a string if necessary), and set *lp to its length in bytes.
The forms differ in that plain "sv_2pvbyte" always processes 'get'
magic; and "sv_2pvbyte_flags" processes 'get' magic if and only if
"flags" contains "SV_GMAGIC".
char * sv_2pv (SV *sv, STRLEN *lp)
char * sv_2pv_flags(SV * const sv, STRLEN * const lp,
const U32 flags)
"sv_2pvbyte"
"sv_2pvbyte_flags"
These implement the various forms of the ""SvPVbyte"" in perlapi
macros. The macros are the preferred interface.
These return a pointer to the byte-encoded representation of the SV,
and set *lp to its length. If the SV is marked as being encoded as
UTF-8, it will be downgraded, if possible, to a byte string. If the
SV cannot be downgraded, they croak.
The forms differ in that plain "sv_2pvbyte" always processes 'get'
magic; and "sv_2pvbyte_flags" processes 'get' magic if and only if
"flags" contains "SV_GMAGIC".
char * sv_2pvbyte (SV *sv, STRLEN * const lp)
char * sv_2pvbyte_flags(SV *sv, STRLEN * const lp,
const U32 flags)
"SvPVCLEAR"
Ensures that sv is a SVt_PV and that its SvCUR is 0, and that it is
properly null terminated. Equivalent to sv_setpvs(""), but more
efficient.
char * SvPVCLEAR(SV* sv)
"SvPVCLEAR_FRESH"
Like SvPVCLEAR, but optimized for newly-minted SVt_PV/PVIV/PVNV/PVMG
that already have a PV buffer allocated, but no SvTHINKFIRST.
char * SvPVCLEAR_FRESH(SV* sv)
"SvPV_force"
"SvPV_force_flags"
"SvPV_force_flags_mutable"
"SvPV_force_flags_nolen"
"SvPV_force_mutable"
"SvPV_force_nolen"
"SvPV_force_nomg"
"SvPV_force_nomg_nolen"
"SvPVbyte_force"
"SvPVbytex_force"
"SvPVutf8_force"
"SvPVutf8x_force"
"SvPVx_force"
These are like "SvPV", returning the string in the SV, but will
force the SV into containing a string ("SvPOK"), and only a string
("SvPOK_only"), by hook or by crook. You need to use one of these
"force" routines if you are going to update the "SvPVX" directly.
Note that coercing an arbitrary scalar into a plain PV will
potentially strip useful data from it. For example if the SV was
"SvROK", then the referent will have its reference count
decremented, and the SV itself may be converted to an "SvPOK" scalar
with a string buffer containing a value such as "ARRAY(0x1234)".
The differences between the forms are:
The forms with "flags" in their names allow you to use the "flags"
parameter to specify to perform 'get' magic (by setting the
"SV_GMAGIC" flag) or to skip 'get' magic (by clearing it). The
other forms do perform 'get' magic, except for the ones with "nomg"
in their names, which skip 'get' magic.
The forms that take a "len" parameter will set that variable to the
byte length of the resultant string (these are macros, so don't use
&len).
The forms with "nolen" in their names indicate they don't have a
"len" parameter. They should be used only when it is known that the
PV is a C string, terminated by a NUL byte, and without intermediate
NUL characters; or when you don't care about its length.
The forms with "mutable" in their names are effectively the same as
those without, but the name emphasizes that the string is modifiable
by the caller, which it is in all the forms.
"SvPVutf8_force" is like "SvPV_force", but converts "sv" to UTF-8
first if not already UTF-8.
"SvPVutf8x_force" is like "SvPVutf8_force", but guarantees to
evaluate "sv" only once; use the more efficient "SvPVutf8_force"
otherwise.
"SvPVbyte_force" is like "SvPV_force", but converts "sv" to byte
representation first if currently encoded as UTF-8. If the SV
cannot be downgraded from UTF-8, this croaks.
"SvPVbytex_force" is like "SvPVbyte_force", but guarantees to
evaluate "sv" only once; use the more efficient "SvPVbyte_force"
otherwise.
char* SvPV_force (SV* sv, STRLEN len)
char* SvPV_force_flags (SV * sv, STRLEN len, U32 flags)
char* SvPV_force_flags_mutable(SV * sv, STRLEN len, U32 flags)
char* SvPV_force_flags_nolen (SV * sv, U32 flags)
char* SvPV_force_mutable (SV * sv, STRLEN len)
char* SvPV_force_nolen (SV* sv)
char* SvPV_force_nomg (SV* sv, STRLEN len)
char* SvPV_force_nomg_nolen (SV * sv)
char* SvPVbyte_force (SV * sv, STRLEN len)
char* SvPVbytex_force (SV * sv, STRLEN len)
char* SvPVutf8_force (SV * sv, STRLEN len)
char* SvPVutf8x_force (SV * sv, STRLEN len)
char* SvPVx_force (SV* sv, STRLEN len)
"SvPV_free"
Frees the PV buffer in "sv", leaving things in a precarious state,
so should only be used as part of a larger operation
void SvPV_free(SV * sv)
"sv_pvn_force_flags"
Get a sensible string out of the SV somehow. If "flags" has the
"SV_GMAGIC" bit set, will "mg_get" on "sv" if appropriate, else not.
"sv_pvn_force" and "sv_pvn_force_nomg" are implemented in terms of
this function. You normally want to use the various wrapper macros
instead: see "SvPV_force" and "SvPV_force_nomg".
char * sv_pvn_force_flags(SV * const sv, STRLEN * const lp,
const U32 flags)
"SvPV_renew"
Low level micro optimization of "SvGROW". It is generally better to
use "SvGROW" instead. This is because "SvPV_renew" ignores
potential issues that "SvGROW" handles. "sv" needs to have a real
"PV" that is unencumbered by things like COW. Using
"SV_CHECK_THINKFIRST" or "SV_CHECK_THINKFIRST_COW_DROP" before
calling this should clean it up, but why not just use "SvGROW" if
you're not sure about the provenance?
void SvPV_renew(SV* sv, STRLEN len)
"SvPV_set"
This is probably not what you want to use, you probably wanted
"sv_usepvn_flags" or "sv_setpvn" or "sv_setpvs".
Set the value of the PV pointer in "sv" to the Perl allocated
"NUL"-terminated string "val". See also "SvIV_set".
Remember to free the previous PV buffer. There are many things to
check. Beware that the existing pointer may be involved in copy-on-
write or other mischief, so do SvOOK_off(sv) and use
"sv_force_normal" or "SvPV_force" (or check the "SvIsCOW" flag)
first to make sure this modification is safe. Then finally, if it is
not a COW, call "SvPV_free" to free the previous PV buffer.
void SvPV_set(SV* sv, char* val)
"SvPV_shrink_to_cur"
Trim any trailing unused memory in the PV of "sv", which needs to
have a real "PV" that is unencumbered by things like COW. Think
first before using this functionality. Is the space saving really
worth giving up COW? Will the needed size of "sv" stay the same?
If the answers are both yes, then use ""SV_CHECK_THINKFIRST"" or
""SV_CHECK_THINKFIRST_COW_DROP"" before calling this.
void SvPV_shrink_to_cur(SV* sv)
"sv_2pvutf8"
"sv_2pvutf8_flags"
These implement the various forms of the ""SvPVutf8"" in perlapi
macros. The macros are the preferred interface.
These return a pointer to the UTF-8-encoded representation of the
SV, and set *lp to its length in bytes. They may cause the SV to be
upgraded to UTF-8 as a side-effect.
The forms differ in that plain "sv_2pvutf8" always processes 'get'
magic; and "sv_2pvutf8_flags" processes 'get' magic if and only if
"flags" contains "SV_GMAGIC".
char * sv_2pvutf8 (SV *sv, STRLEN * const lp)
char * sv_2pvutf8_flags(SV *sv, STRLEN * const lp,
const U32 flags)
"SvPVX"
"SvPVX_const"
"SvPVX_mutable"
"SvPVXx"
These return a pointer to the physical string in the SV. The SV
must contain a string. Prior to 5.9.3 it is not safe to execute
these unless the SV's type >= "SVt_PV".
These are also used to store the name of an autoloaded subroutine in
an XS AUTOLOAD routine. See "Autoloading with XSUBs" in perlguts.
"SvPVXx" is identical to "SvPVX".
"SvPVX_mutable" is merely a synonym for "SvPVX", but its name
emphasizes that the string is modifiable by the caller.
"SvPVX_const" differs in that the return value has been cast so that
the compiler will complain if you were to try to modify the contents
of the string, (unless you cast away const yourself).
char* SvPVX (SV* sv)
const char* SvPVX_const (SV* sv)
char* SvPVX_mutable(SV* sv)
char* SvPVXx (SV* sv)
"SvPVXtrue"
Returns a boolean as to whether or not "sv" contains a PV that is
considered TRUE. FALSE is returned if "sv" doesn't contain a PV, or
if the PV it does contain is zero length, or consists of just the
single character '0'. Every other PV value is considered TRUE.
As of Perl v5.37.1, "sv" is evaluated exactly once; in earlier
releases, it could be evaluated more than once.
bool SvPVXtrue(SV *sv)
"SvREADONLY"
Returns true if the argument is readonly, otherwise returns false.
Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY(SV* sv)
"SvREADONLY_off"
Mark an object as not-readonly. Exactly what this mean depends on
the object type. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY_off(SV* sv)
"SvREADONLY_on"
Mark an object as readonly. Exactly what this means depends on the
object type. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY_on(SV* sv)
"sv_ref"
Returns a SV describing what the SV passed in is a reference to.
dst can be a SV to be set to the description or NULL, in which case
a mortal SV is returned.
If ob is true and the SV is blessed, the description is the class
name, otherwise it is the type of the SV, "SCALAR", "ARRAY" etc.
SV * sv_ref(SV *dst, const SV * const sv, const int ob)
"SvREFCNT"
Returns the value of the object's reference count. Exposed to perl
code via Internals::SvREFCNT().
U32 SvREFCNT(SV* sv)
"SvREFCNT_dec"
"SvREFCNT_dec_set_NULL"
"SvREFCNT_dec_ret_NULL"
"SvREFCNT_dec_NN"
These decrement the reference count of the given SV.
"SvREFCNT_dec_NN" may only be used when "sv" is known to not be
"NULL".
The function SvREFCNT_dec_ret_NULL() is identical to the
SvREFCNT_dec() except it returns a NULL "SV *". It is used by
SvREFCNT_dec_set_NULL() which is a macro which will, when passed a
non-NULL argument, decrement the reference count of its argument and
then set it to NULL. You can replace code of the following form:
if (sv) {
SvREFCNT_dec_NN(sv);
sv = NULL;
}
with
SvREFCNT_dec_set_NULL(sv);
void SvREFCNT_dec (SV *sv)
void SvREFCNT_dec_set_NULL(SV *sv)
SV * SvREFCNT_dec_ret_NULL(SV *sv)
void SvREFCNT_dec_NN (SV *sv)
"SvREFCNT_inc"
"SvREFCNT_inc_NN"
"SvREFCNT_inc_simple"
"SvREFCNT_inc_simple_NN"
"SvREFCNT_inc_simple_void"
"SvREFCNT_inc_simple_void_NN"
"SvREFCNT_inc_void"
"SvREFCNT_inc_void_NN"
These all increment the reference count of the given SV. The ones
without "void" in their names return the SV.
"SvREFCNT_inc" is the base operation; the rest are optimizations if
various input constraints are known to be true; hence, all can be
replaced with "SvREFCNT_inc".
"SvREFCNT_inc_NN" can only be used if you know "sv" is not "NULL".
Since we don't have to check the NULLness, it's faster and smaller.
"SvREFCNT_inc_void" can only be used if you don't need the return
value. The macro doesn't need to return a meaningful value.
"SvREFCNT_inc_void_NN" can only be used if you both don't need the
return value, and you know that "sv" is not "NULL". The macro
doesn't need to return a meaningful value, or check for NULLness, so
it's smaller and faster.
"SvREFCNT_inc_simple" can only be used with expressions without side
effects. Since we don't have to store a temporary value, it's
faster.
"SvREFCNT_inc_simple_NN" can only be used with expressions without
side effects and you know "sv" is not "NULL". Since we don't have
to store a temporary value, nor check for NULLness, it's faster and
smaller.
"SvREFCNT_inc_simple_void" can only be used with expressions without
side effects and you don't need the return value.
"SvREFCNT_inc_simple_void_NN" can only be used with expressions
without side effects, you don't need the return value, and you know
"sv" is not "NULL".
SV * SvREFCNT_inc (SV *sv)
SV * SvREFCNT_inc_NN (SV *sv)
SV* SvREFCNT_inc_simple (SV* sv)
SV* SvREFCNT_inc_simple_NN (SV* sv)
void SvREFCNT_inc_simple_void (SV* sv)
void SvREFCNT_inc_simple_void_NN(SV* sv)
void SvREFCNT_inc_void (SV *sv)
void SvREFCNT_inc_void_NN (SV* sv)
"sv_reftype"
Returns a string describing what the SV is a reference to.
If ob is true and the SV is blessed, the string is the class name,
otherwise it is the type of the SV, "SCALAR", "ARRAY" etc.
const char * sv_reftype(const SV * const sv, const int ob)
"sv_replace"
Make the first argument a copy of the second, then delete the
original. The target SV physically takes over ownership of the body
of the source SV and inherits its flags; however, the target keeps
any magic it owns, and any magic in the source is discarded. Note
that this is a rather specialist SV copying operation; most of the
time you'll want to use "sv_setsv" or one of its many macro front-
ends.
void sv_replace(SV * const sv, SV * const nsv)
"sv_report_used"
Dump the contents of all SVs not yet freed (debugging aid).
void sv_report_used()
"sv_reset"
Underlying implementation for the "reset" Perl function. Note that
the perl-level function is vaguely deprecated.
void sv_reset(const char *s, HV * const stash)
"SvROK"
Tests if the SV is an RV.
U32 SvROK(SV* sv)
"SvROK_off"
Unsets the RV status of an SV.
void SvROK_off(SV* sv)
"SvROK_on"
Tells an SV that it is an RV.
void SvROK_on(SV* sv)
"SvRV"
Dereferences an RV to return the SV.
SV* SvRV(SV* sv)
"SvRV_set"
Set the value of the RV pointer in "sv" to val. See "SvIV_set".
void SvRV_set(SV* sv, SV* val)
"sv_rvunweaken"
Unweaken a reference: Clear the "SvWEAKREF" flag on this RV; remove
the backreference to this RV from the array of backreferences
associated with the target SV, increment the refcount of the target.
Silently ignores "undef" and warns on non-weak references.
SV * sv_rvunweaken(SV * const sv)
"sv_rvweaken"
Weaken a reference: set the "SvWEAKREF" flag on this RV; give the
referred-to SV "PERL_MAGIC_backref" magic if it hasn't already; and
push a back-reference to this RV onto the array of backreferences
associated with that magic. If the RV is magical, set magic will be
called after the RV is cleared. Silently ignores "undef" and warns
on already-weak references.
SV * sv_rvweaken(SV * const sv)
"sv_setbool"
"sv_setbool_mg"
These set an SV to a true or false boolean value, upgrading first if
necessary.
They differ only in that "sv_setbool_mg" handles 'set' magic;
"sv_setbool" does not.
void sv_setbool(SV *sv, bool b)
"sv_set_bool"
Equivalent to "sv_setsv(sv, bool_val ? &Pl_sv_yes : &PL_sv_no)", but
may be made more efficient in the future. Doesn't handle set magic.
The perl equivalent is "$sv = !!$expr;".
Introduced in perl 5.35.11.
void sv_set_bool(SV *sv, const bool bool_val)
"sv_set_false"
Equivalent to "sv_setsv(sv, &PL_sv_no)", but may be made more
efficient in the future. Doesn't handle set magic.
The perl equivalent is "$sv = !1;".
Introduced in perl 5.35.11.
void sv_set_false(SV *sv)
"sv_setiv"
"sv_setiv_mg"
These copy an integer into the given SV, upgrading first if
necessary.
They differ only in that "sv_setiv_mg" handles 'set' magic;
"sv_setiv" does not.
void sv_setiv (SV * const sv, const IV num)
void sv_setiv_mg(SV * const sv, const IV i)
"SvSETMAGIC"
Invokes "mg_set" on an SV if it has 'set' magic. This is necessary
after modifying a scalar, in case it is a magical variable like $|
or a tied variable (it calls "STORE"). This macro evaluates its
argument more than once.
void SvSETMAGIC(SV* sv)
"SvSetMagicSV"
"SvSetMagicSV_nosteal"
"SvSetSV"
"SvSetSV_nosteal"
if "dsv" is the same as "ssv", these do nothing. Otherwise they all
call some form of "sv_setsv". They may evaluate their arguments
more than once.
The only differences are:
"SvSetMagicSV" and "SvSetMagicSV_nosteal" perform any required 'set'
magic afterwards on the destination SV; "SvSetSV" and
"SvSetSV_nosteal" do not.
"SvSetSV_nosteal" "SvSetMagicSV_nosteal" call a non-destructive
version of "sv_setsv".
void SvSetMagicSV(SV* dsv, SV* ssv)
"sv_setnv"
"sv_setnv_mg"
These copy a double into the given SV, upgrading first if necessary.
They differ only in that "sv_setnv_mg" handles 'set' magic;
"sv_setnv" does not.
void sv_setnv(SV * const sv, const NV num)
"sv_setpv"
"sv_setpv_mg"
"sv_setpvn"
"sv_setpvn_fresh"
"sv_setpvn_mg"
"sv_setpvs"
"sv_setpvs_mg"
These copy a string into the SV "sv", making sure it is
"SvPOK_only".
In the "pvs" forms, the string must be a C literal string, enclosed
in double quotes.
In the "pvn" forms, the first byte of the string is pointed to by
"ptr", and "len" indicates the number of bytes to be copied,
potentially including embedded "NUL" characters.
In the plain "pv" forms, "ptr" points to a NUL-terminated C string.
That is, it points to the first byte of the string, and the copy
proceeds up through the first encountered "NUL" byte.
In the forms that take a "ptr" argument, if it is NULL, the SV will
become undefined.
The UTF-8 flag is not changed by these functions.
A terminating NUL byte is guaranteed in the result.
The "_mg" forms handle 'set' magic; the other forms skip all magic.
"sv_setpvn_fresh" is a cut-down alternative to "sv_setpvn", intended
ONLY to be used with a fresh sv that has been upgraded to a SVt_PV,
SVt_PVIV, SVt_PVNV, or SVt_PVMG.
void sv_setpv (SV * const sv, const char * const ptr)
void sv_setpv_mg (SV * const sv, const char * const ptr)
void sv_setpvn (SV * const sv, const char * const ptr,
const STRLEN len)
void sv_setpvn_fresh(SV * const sv, const char * const ptr,
const STRLEN len)
void sv_setpvn_mg (SV * const sv, const char * const ptr,
const STRLEN len)
void sv_setpvs (SV* sv, "literal string")
void sv_setpvs_mg (SV* sv, "literal string")
"sv_setpv_bufsize"
Sets the SV to be a string of "cur" bytes length, with at least
"len" bytes available. Ensures that there is a null byte at
"SvEND".
Returns a char * pointer to the SvPV buffer.
The caller must set the first "cur" bytes of "sv" before the first
use of its contents. This means that if "cur" is zero, the SV is
immediately fully formed and ready to use, just like any other SV
containing an empty string.
char * sv_setpv_bufsize(SV * const sv, const STRLEN cur,
const STRLEN len)
"sv_setpvf"
"sv_setpvf_mg"
"sv_setpvf_mg_nocontext"
"sv_setpvf_nocontext"
These work like "sv_catpvf" but copy the text into the SV instead of
appending it.
The differences between these are:
"sv_setpvf_mg" and "sv_setpvf_mg_nocontext" perform 'set' magic;
"sv_setpvf" and "sv_setpvf_nocontext" skip all magic.
"sv_setpvf_nocontext" and "sv_setpvf_mg_nocontext" do not take a
thread context ("aTHX") parameter, so are used in situations where
the caller doesn't already have the thread context.
The UTF-8 flag is not changed by these functions.
NOTE: "sv_setpvf" must be explicitly called as "Perl_sv_setpvf" with
an "aTHX_" parameter.
NOTE: "sv_setpvf_mg" must be explicitly called as
"Perl_sv_setpvf_mg" with an "aTHX_" parameter.
void Perl_sv_setpvf (pTHX_ SV * const sv,
const char * const pat, ...)
void Perl_sv_setpvf_mg (pTHX_ SV * const sv,
const char * const pat, ...)
void sv_setpvf_mg_nocontext(SV * const sv,
const char * const pat, ...)
void sv_setpvf_nocontext (SV * const sv,
const char * const pat, ...)
"sv_setref_iv"
Copies an integer into a new SV, optionally blessing the SV. The
"rv" argument will be upgraded to an RV. That RV will be modified
to point to the new SV. The "classname" argument indicates the
package for the blessing. Set "classname" to "NULL" to avoid the
blessing. The new SV will have a reference count of 1, and the RV
will be returned.
SV * sv_setref_iv(SV * const rv, const char * const classname,
const IV iv)
"sv_setref_nv"
Copies a double into a new SV, optionally blessing the SV. The "rv"
argument will be upgraded to an RV. That RV will be modified to
point to the new SV. The "classname" argument indicates the package
for the blessing. Set "classname" to "NULL" to avoid the blessing.
The new SV will have a reference count of 1, and the RV will be
returned.
SV * sv_setref_nv(SV * const rv, const char * const classname,
const NV nv)
"sv_setref_pv"
Copies a pointer into a new SV, optionally blessing the SV. The
"rv" argument will be upgraded to an RV. That RV will be modified
to point to the new SV. If the "pv" argument is "NULL", then
"PL_sv_undef" will be placed into the SV. The "classname" argument
indicates the package for the blessing. Set "classname" to "NULL"
to avoid the blessing. The new SV will have a reference count of 1,
and the RV will be returned.
Do not use with other Perl types such as HV, AV, SV, CV, because
those objects will become corrupted by the pointer copy process.
Note that "sv_setref_pvn" copies the string while this copies the
pointer.
SV * sv_setref_pv(SV * const rv, const char * const classname,
void * const pv)
"sv_setref_pvn"
Copies a string into a new SV, optionally blessing the SV. The
length of the string must be specified with "n". The "rv" argument
will be upgraded to an RV. That RV will be modified to point to the
new SV. The "classname" argument indicates the package for the
blessing. Set "classname" to "NULL" to avoid the blessing. The new
SV will have a reference count of 1, and the RV will be returned.
Note that "sv_setref_pv" copies the pointer while this copies the
string.
SV * sv_setref_pvn(SV * const rv, const char * const classname,
const char * const pv, const STRLEN n)
"sv_setref_pvs"
Like "sv_setref_pvn", but takes a literal string instead of a
string/length pair.
SV * sv_setref_pvs(SV *const rv, const char *const classname,
"literal string")
"sv_setref_uv"
Copies an unsigned integer into a new SV, optionally blessing the
SV. The "rv" argument will be upgraded to an RV. That RV will be
modified to point to the new SV. The "classname" argument indicates
the package for the blessing. Set "classname" to "NULL" to avoid
the blessing. The new SV will have a reference count of 1, and the
RV will be returned.
SV * sv_setref_uv(SV * const rv, const char * const classname,
const UV uv)
"sv_setrv_inc"
"sv_setrv_inc_mg"
As "sv_setrv_noinc" but increments the reference count of ref.
"sv_setrv_inc_mg" will invoke 'set' magic on the SV; "sv_setrv_inc"
will not.
void sv_setrv_inc(SV * const sv, SV * const ref)
"sv_setrv_noinc"
"sv_setrv_noinc_mg"
Copies an SV pointer into the given SV as an SV reference, upgrading
it if necessary. After this, SvRV(sv) is equal to ref. This does not
adjust the reference count of ref. The reference ref must not be
NULL.
"sv_setrv_noinc_mg" will invoke 'set' magic on the SV;
"sv_setrv_noinc" will not.
void sv_setrv_noinc(SV * const sv, SV * const ref)
"sv_setsv"
"sv_setsv_flags"
"sv_setsv_mg"
"sv_setsv_nomg"
These copy the contents of the source SV "ssv" into the destination
SV "dsv". "ssv" may be destroyed if it is mortal, so don't use
these functions if the source SV needs to be reused. Loosely
speaking, they perform a copy-by-value, obliterating any previous
content of the destination.
They differ only in that:
"sv_setsv" calls 'get' magic on "ssv", but skips 'set' magic on
"dsv".
"sv_setsv_mg" calls both 'get' magic on "ssv" and 'set' magic on
"dsv".
"sv_setsv_nomg" skips all magic.
"sv_setsv_flags" has a "flags" parameter which you can use to
specify any combination of magic handling, and also you can specify
"SV_NOSTEAL" so that the buffers of temps will not be stolen.
You probably want to instead use one of the assortment of wrappers,
such as "SvSetSV", "SvSetSV_nosteal", "SvSetMagicSV" and
"SvSetMagicSV_nosteal".
"sv_setsv_flags" is the primary function for copying scalars, and
most other copy-ish functions and macros use it underneath.
void sv_setsv (SV *dsv, SV *ssv)
void sv_setsv_flags(SV *dsv, SV *ssv, const I32 flags)
void sv_setsv_mg (SV * const dsv, SV * const ssv)
void sv_setsv_nomg (SV *dsv, SV *ssv)
"sv_set_true"
Equivalent to "sv_setsv(sv, &PL_sv_yes)", but may be made more
efficient in the future. Doesn't handle set magic.
The perl equivalent is "$sv = !0;".
Introduced in perl 5.35.11.
void sv_set_true(SV *sv)
"sv_set_undef"
Equivalent to "sv_setsv(sv, &PL_sv_undef)", but more efficient.
Doesn't handle set magic.
The perl equivalent is "$sv = undef;". Note that it doesn't free any
string buffer, unlike "undef $sv".
Introduced in perl 5.25.12.
void sv_set_undef(SV *sv)
"sv_setuv"
"sv_setuv_mg"
These copy an unsigned integer into the given SV, upgrading first if
necessary.
They differ only in that "sv_setuv_mg" handles 'set' magic;
"sv_setuv" does not.
void sv_setuv (SV * const sv, const UV num)
void sv_setuv_mg(SV * const sv, const UV u)
"SvSHARE"
Arranges for "sv" to be shared between threads if a suitable module
has been loaded.
void SvSHARE(SV* sv)
"SvSHARED_HASH"
Returns the hash for "sv" created by "newSVpvn_share".
struct hek* SvSHARED_HASH(SV * sv)
"SvSTASH"
Returns the stash of the SV.
HV* SvSTASH(SV* sv)
"SvSTASH_set"
Set the value of the STASH pointer in "sv" to val. See "SvIV_set".
void SvSTASH_set(SV* sv, HV* val)
"sv_streq"
A convenient shortcut for calling "sv_streq_flags" with the
"SV_GMAGIC" flag. This function basically behaves like the Perl code
"$sv1 eq $sv2".
bool sv_streq(SV *sv1, SV *sv2)
"sv_streq_flags"
Returns a boolean indicating whether the strings in the two SVs are
identical. If the flags argument has the "SV_GMAGIC" bit set, it
handles get-magic too. Will coerce its args to strings if necessary.
Treats "NULL" as undef. Correctly handles the UTF8 flag.
If flags does not have the "SV_SKIP_OVERLOAD" bit set, an attempt to
use "eq" overloading will be made. If such overloading does not
exist or the flag is set, then regular string comparison will be
used instead.
bool sv_streq_flags(SV *sv1, SV *sv2, const U32 flags)
"SvTRUE"
"SvTRUE_NN"
"SvTRUE_nomg"
"SvTRUE_nomg_NN"
"SvTRUEx"
These return a boolean indicating whether Perl would evaluate the SV
as true or false. See "SvOK" for a defined/undefined test.
As of Perl 5.32, all are guaranteed to evaluate "sv" only once.
Prior to that release, only "SvTRUEx" guaranteed single evaluation;
now "SvTRUEx" is identical to "SvTRUE".
"SvTRUE_nomg" and "TRUE_nomg_NN" do not perform 'get' magic; the
others do unless the scalar is already "SvPOK", "SvIOK", or "SvNOK"
(the public, not the private flags).
"SvTRUE_NN" is like "SvTRUE", but "sv" is assumed to be non-null
(NN). If there is a possibility that it is NULL, use plain
"SvTRUE".
"SvTRUE_nomg_NN" is like "SvTRUE_nomg", but "sv" is assumed to be
non-null (NN). If there is a possibility that it is NULL, use plain
"SvTRUE_nomg".
bool SvTRUE(SV *sv)
"SvTYPE"
Returns the type of the SV. See "svtype".
svtype SvTYPE(SV* sv)
"SvUNLOCK"
Releases a mutual exclusion lock on "sv" if a suitable module has
been loaded.
void SvUNLOCK(SV* sv)
"sv_unmagic"
Removes all magic of type "type" from an SV.
int sv_unmagic(SV * const sv, const int type)
"sv_unmagicext"
Removes all magic of type "type" with the specified "vtbl" from an
SV.
int sv_unmagicext(SV * const sv, const int type,
const MGVTBL *vtbl)
"sv_unref"
Unsets the RV status of the SV, and decrements the reference count
of whatever was being referenced by the RV. This can almost be
thought of as a reversal of "newSVrv". This is "sv_unref_flags"
with the "flag" being zero. See "SvROK_off".
void sv_unref(SV *sv)
"sv_unref_flags"
Unsets the RV status of the SV, and decrements the reference count
of whatever was being referenced by the RV. This can almost be
thought of as a reversal of "newSVrv". The "cflags" argument can
contain "SV_IMMEDIATE_UNREF" to force the reference count to be
decremented (otherwise the decrementing is conditional on the
reference count being different from one or the reference being a
readonly SV). See "SvROK_off".
void sv_unref_flags(SV * const ref, const U32 flags)
"SvUOK"
Returns a boolean indicating whether the SV contains an integer that
must be interpreted as unsigned. A non-negative integer whose value
is within the range of both an IV and a UV may be flagged as either
"SvUOK" or "SvIOK".
bool SvUOK(SV* sv)
"SvUPGRADE"
Used to upgrade an SV to a more complex form. Uses "sv_upgrade" to
perform the upgrade if necessary. See "svtype".
void SvUPGRADE(SV* sv, svtype type)
"sv_upgrade"
Upgrade an SV to a more complex form. Generally adds a new body
type to the SV, then copies across as much information as possible
from the old body. It croaks if the SV is already in a more complex
form than requested. You generally want to use the "SvUPGRADE"
macro wrapper, which checks the type before calling "sv_upgrade",
and hence does not croak. See also "svtype".
void sv_upgrade(SV * const sv, svtype new_type)
"sv_usepvn"
"sv_usepvn_flags"
"sv_usepvn_mg"
These tell an SV to use "ptr" for its string value. Normally SVs
have their string stored inside the SV, but these tell the SV to use
an external string instead.
"ptr" should point to memory that was allocated by ""Newx"". It
must be the start of a "Newx"-ed block of memory, and not a pointer
to the middle of it (beware of "OOK" and copy-on-write), and not be
from a non-"Newx" memory allocator like "malloc". The string
length, "len", must be supplied. By default this function will
""Renew"" (i.e. realloc, move) the memory pointed to by "ptr", so
that the pointer should not be freed or used by the programmer after
giving it to "sv_usepvn", and neither should any pointers from
"behind" that pointer (e.g., "ptr" + 1) be used.
In the "sv_usepvn_flags" form, if "flags & SV_SMAGIC" is true,
"SvSETMAGIC" is called before returning. And if
"flags & SV_HAS_TRAILING_NUL" is true, then "ptr[len]" must be
"NUL", and the realloc will be skipped (i.e., the buffer is actually
at least 1 byte longer than "len", and already meets the
requirements for storing in "SvPVX").
"sv_usepvn" is merely "sv_usepvn_flags" with "flags" set to 0, so
'set' magic is skipped.
"sv_usepvn_mg" is merely "sv_usepvn_flags" with "flags" set to
"SV_SMAGIC", so 'set' magic is performed.
void sv_usepvn (SV *sv, char *ptr, STRLEN len)
void sv_usepvn_flags(SV * const sv, char *ptr, const STRLEN len,
const U32 flags)
void sv_usepvn_mg (SV *sv, char *ptr, STRLEN len)
"sv_utf8_decode"
If the PV of the SV is an octet sequence in Perl's extended UTF-8
and contains a multiple-byte character, the "SvUTF8" flag is turned
on so that it looks like a character. If the PV contains only
single-byte characters, the "SvUTF8" flag stays off. Scans PV for
validity and returns FALSE if the PV is invalid UTF-8.
bool sv_utf8_decode(SV * const sv)
"sv_utf8_downgrade"
"sv_utf8_downgrade_flags"
"sv_utf8_downgrade_nomg"
These attempt to convert the PV of an SV from characters to bytes.
If the PV contains a character that cannot fit in a byte, this
conversion will fail; in this case, "FALSE" is returned if "fail_ok"
is true; otherwise they croak.
They are not a general purpose Unicode to byte encoding interface:
use the "Encode" extension for that.
They differ only in that:
"sv_utf8_downgrade" processes 'get' magic on "sv".
"sv_utf8_downgrade_nomg" does not.
"sv_utf8_downgrade_flags" has an additional "flags" parameter in
which you can specify "SV_GMAGIC" to process 'get' magic, or leave
it cleared to not process 'get' magic.
bool sv_utf8_downgrade (SV * const sv, const bool fail_ok)
bool sv_utf8_downgrade_flags(SV * const sv, const bool fail_ok,
const U32 flags)
bool sv_utf8_downgrade_nomg (SV * const sv, const bool fail_ok)
"sv_utf8_encode"
Converts the PV of an SV to UTF-8, but then turns the "SvUTF8" flag
off so that it looks like octets again.
void sv_utf8_encode(SV * const sv)
"SvUTF8_off"
Unsets the UTF-8 status of an SV (the data is not changed, just the
flag). Do not use frivolously.
void SvUTF8_off(SV *sv)
"SvUTF8_on"
Turn on the UTF-8 status of an SV (the data is not changed, just the
flag). Do not use frivolously.
void SvUTF8_on(SV *sv)
"sv_utf8_upgrade"
"sv_utf8_upgrade_flags"
"sv_utf8_upgrade_flags_grow"
"sv_utf8_upgrade_nomg"
These convert the PV of an SV to its UTF-8-encoded form. The SV is
forced to string form if it is not already. They always set the
"SvUTF8" flag to avoid future validity checks even if the whole
string is the same in UTF-8 as not. They return the number of bytes
in the converted string
The forms differ in just two ways. The main difference is whether
or not they perform 'get magic' on "sv". "sv_utf8_upgrade_nomg"
skips 'get magic'; "sv_utf8_upgrade" performs it; and
"sv_utf8_upgrade_flags" and "sv_utf8_upgrade_flags_grow" either
perform it (if the "SV_GMAGIC" bit is set in "flags") or don't (if
that bit is cleared).
The other difference is that "sv_utf8_upgrade_flags_grow" has an
additional parameter, "extra", which allows the caller to specify an
amount of space to be reserved as spare beyond what is needed for
the actual conversion. This is used when the caller knows it will
soon be needing yet more space, and it is more efficient to request
space from the system in a single call. This form is otherwise
identical to "sv_utf8_upgrade_flags".
These are not a general purpose byte encoding to Unicode interface:
use the Encode extension for that.
The "SV_FORCE_UTF8_UPGRADE" flag is now ignored.
STRLEN sv_utf8_upgrade (SV *sv)
STRLEN sv_utf8_upgrade_flags (SV * const sv, const I32 flags)
STRLEN sv_utf8_upgrade_flags_grow(SV * const sv, const I32 flags,
STRLEN extra)
STRLEN sv_utf8_upgrade_nomg (SV *sv)
"SvUTF8"
Returns a U32 value indicating the UTF-8 status of an SV. If things
are set-up properly, this indicates whether or not the SV contains
UTF-8 encoded data. You should use this after a call to "SvPV" or
one of its variants, in case any call to string overloading updates
the internal flag.
If you want to take into account the bytes pragma, use "DO_UTF8"
instead.
U32 SvUTF8(SV* sv)
"SvUV"
"SvUV_nomg"
"SvUVx"
These each coerce the given SV to UV and return it. The returned
value in many circumstances will get stored in "sv"'s UV slot, but
not in all cases. (Use "sv_setuv" to make sure it does).
As of 5.37.1, all are guaranteed to evaluate "sv" only once.
"SvUVx" is now identical to "SvUV", but prior to 5.37.1, it was the
only form guaranteed to evaluate "sv" only once.
UV SvUV(SV *sv)
"sv_2uv_flags"
Return the unsigned integer value of an SV, doing any necessary
string conversion. If "flags" has the "SV_GMAGIC" bit set, does an
mg_get() first. Normally used via the SvUV(sv) and SvUVx(sv)
macros.
UV sv_2uv_flags(SV * const sv, const I32 flags)
"SvUV_set"
Set the value of the UV pointer in "sv" to val. See "SvIV_set".
void SvUV_set(SV* sv, UV val)
"SvUVX"
Returns the raw value in the SV's UV slot, without checks or
conversions. Only use when you are sure "SvIOK" is true. See also
"SvUV".
UV SvUVX(SV* sv)
"SvUVXx"
"DEPRECATED!" It is planned to remove "SvUVXx" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
This is an unnecessary synonym for "SvUVX"
UV SvUVXx(SV* sv)
"sv_vcatpvf"
"sv_vcatpvf_mg"
These process their arguments like "sv_vcatpvfn" called with a non-
null C-style variable argument list, and append the formatted output
to "sv".
They differ only in that "sv_vcatpvf_mg" performs 'set' magic;
"sv_vcatpvf" skips 'set' magic.
Both perform 'get' magic.
They are usually accessed via their frontends "sv_catpvf" and
"sv_catpvf_mg".
void sv_vcatpvf(SV * const sv, const char * const pat,
va_list * const args)
"sv_vcatpvfn"
"sv_vcatpvfn_flags"
These process their arguments like vsprintf(3) and append the
formatted output to an SV. They use an array of SVs if the C-style
variable argument list is missing ("NULL"). Argument reordering
(using format specifiers like "%2$d" or "%*2$d") is supported only
when using an array of SVs; using a C-style "va_list" argument list
with a format string that uses argument reordering will yield an
exception.
When running with taint checks enabled, they indicate via
"maybe_tainted" if results are untrustworthy (often due to the use
of locales).
They assume that "pat" has the same utf8-ness as "sv". It's the
caller's responsibility to ensure that this is so.
They differ in that "sv_vcatpvfn_flags" has a "flags" parameter in
which you can set or clear the "SV_GMAGIC" and/or SV_SMAGIC flags,
to specify which magic to handle or not handle; whereas plain
"sv_vcatpvfn" always specifies both 'get' and 'set' magic.
They are usually used via one of the frontends ""sv_vcatpvf"" and
""sv_vcatpvf_mg"".
void sv_vcatpvfn (SV * const sv, const char * const pat,
const STRLEN patlen, va_list * const args,
SV ** const svargs, const Size_t sv_count,
bool * const maybe_tainted)
void sv_vcatpvfn_flags(SV * const sv, const char * const pat,
const STRLEN patlen, va_list * const args,
SV ** const svargs, const Size_t sv_count,
bool * const maybe_tainted,
const U32 flags)
"SvVOK"
Returns a boolean indicating whether the SV contains a v-string.
bool SvVOK(SV* sv)
"sv_vsetpvf"
"sv_vsetpvf_mg"
These work like "sv_vcatpvf" but copy the text into the SV instead
of appending it.
They differ only in that "sv_vsetpvf_mg" performs 'set' magic;
"sv_vsetpvf" skips all magic.
They are usually used via their frontends, "sv_setpvf" and
"sv_setpvf_mg".
The UTF-8 flag is not changed by these functions.
void sv_vsetpvf(SV * const sv, const char * const pat,
va_list * const args)
"sv_vsetpvfn"
Works like "sv_vcatpvfn" but copies the text into the SV instead of
appending it.
The UTF-8 flag is not changed by this function.
Usually used via one of its frontends ""sv_vsetpvf"" and
""sv_vsetpvf_mg"".
void sv_vsetpvfn(SV * const sv, const char * const pat,
const STRLEN patlen, va_list * const args,
SV ** const svargs, const Size_t sv_count,
bool * const maybe_tainted)
"SvVSTRING_mg"
Returns the vstring magic, or NULL if none
MAGIC* SvVSTRING_mg(SV * sv)
"vnewSVpvf"
Like "newSVpvf" but the arguments are an encapsulated argument list.
SV * vnewSVpvf(const char * const pat, va_list * const args)
Tainting
"SvTAINT"
Taints an SV if tainting is enabled, and if some input to the
current expression is tainted--usually a variable, but possibly also
implicit inputs such as locale settings. "SvTAINT" propagates that
taintedness to the outputs of an expression in a pessimistic
fashion; i.e., without paying attention to precisely which outputs
are influenced by which inputs.
void SvTAINT(SV* sv)
"SvTAINTED"
Checks to see if an SV is tainted. Returns TRUE if it is, FALSE if
not.
bool SvTAINTED(SV* sv)
"SvTAINTED_off"
Untaints an SV. Be very careful with this routine, as it short-
circuits some of Perl's fundamental security features. XS module
authors should not use this function unless they fully understand
all the implications of unconditionally untainting the value.
Untainting should be done in the standard perl fashion, via a
carefully crafted regexp, rather than directly untainting variables.
void SvTAINTED_off(SV* sv)
"SvTAINTED_on"
Marks an SV as tainted if tainting is enabled.
void SvTAINTED_on(SV* sv)
Time
"ASCTIME_R_PROTO"
This symbol encodes the prototype of "asctime_r". It is zero if
"d_asctime_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_asctime_r" is defined.
"CTIME_R_PROTO"
This symbol encodes the prototype of "ctime_r". It is zero if
"d_ctime_r" is undef, and one of the "REENTRANT_PROTO_T_ABC" macros
of reentr.h if "d_ctime_r" is defined.
"GMTIME_MAX"
This symbol contains the maximum value for the "time_t" offset that
the system function gmtime () accepts, and defaults to 0
"GMTIME_MIN"
This symbol contains the minimum value for the "time_t" offset that
the system function gmtime () accepts, and defaults to 0
"GMTIME_R_PROTO"
This symbol encodes the prototype of "gmtime_r". It is zero if
"d_gmtime_r" is undef, and one of the "REENTRANT_PROTO_T_ABC" macros
of reentr.h if "d_gmtime_r" is defined.
"HAS_ASCTIME_R"
This symbol, if defined, indicates that the "asctime_r" routine is
available to asctime re-entrantly.
"HAS_ASCTIME64"
This symbol, if defined, indicates that the "asctime64" () routine
is available to do the 64bit variant of asctime ()
"HAS_CTIME_R"
This symbol, if defined, indicates that the "ctime_r" routine is
available to ctime re-entrantly.
"HAS_CTIME64"
This symbol, if defined, indicates that the "ctime64" () routine is
available to do the 64bit variant of ctime ()
"HAS_DIFFTIME"
This symbol, if defined, indicates that the "difftime" routine is
available.
"HAS_DIFFTIME64"
This symbol, if defined, indicates that the "difftime64" () routine
is available to do the 64bit variant of difftime ()
"HAS_FUTIMES"
This symbol, if defined, indicates that the "futimes" routine is
available to change file descriptor time stamps with "struct
timevals".
"HAS_GETITIMER"
This symbol, if defined, indicates that the "getitimer" routine is
available to return interval timers.
"HAS_GETTIMEOFDAY"
This symbol, if defined, indicates that the gettimeofday() system
call is available for a sub-second accuracy clock. Usually, the file
sys/resource.h needs to be included (see "I_SYS_RESOURCE"). The
type "Timeval" should be used to refer to ""struct timeval"".
"HAS_GMTIME_R"
This symbol, if defined, indicates that the "gmtime_r" routine is
available to gmtime re-entrantly.
"HAS_GMTIME64"
This symbol, if defined, indicates that the "gmtime64" () routine is
available to do the 64bit variant of gmtime ()
"HAS_LOCALTIME_R"
This symbol, if defined, indicates that the "localtime_r" routine is
available to localtime re-entrantly.
"HAS_LOCALTIME64"
This symbol, if defined, indicates that the "localtime64" () routine
is available to do the 64bit variant of localtime ()
"HAS_MKTIME"
This symbol, if defined, indicates that the "mktime" routine is
available.
"HAS_MKTIME64"
This symbol, if defined, indicates that the "mktime64" () routine is
available to do the 64bit variant of mktime ()
"HAS_NANOSLEEP"
This symbol, if defined, indicates that the "nanosleep" system call
is available to sleep with 1E-9 sec accuracy.
"HAS_SETITIMER"
This symbol, if defined, indicates that the "setitimer" routine is
available to set interval timers.
"HAS_STRFTIME"
This symbol, if defined, indicates that the "strftime" routine is
available to do time formatting.
"HAS_TIME"
This symbol, if defined, indicates that the time() routine exists.
"HAS_TIMEGM"
This symbol, if defined, indicates that the "timegm" routine is
available to do the opposite of gmtime ()
"HAS_TIMES"
This symbol, if defined, indicates that the times() routine exists.
Note that this became obsolete on some systems ("SUNOS"), which now
use getrusage(). It may be necessary to include sys/times.h.
"HAS_TM_TM_GMTOFF"
This symbol, if defined, indicates to the C program that the "struct
tm" has a "tm_gmtoff" field.
"HAS_TM_TM_ZONE"
This symbol, if defined, indicates to the C program that the "struct
tm" has a "tm_zone" field.
"HAS_TZNAME"
This symbol, if defined, indicates that the "tzname[]" array is
available to access timezone names.
"HAS_USLEEP"
This symbol, if defined, indicates that the "usleep" routine is
available to let the process sleep on a sub-second accuracy.
"HAS_USLEEP_PROTO"
This symbol, if defined, indicates that the system provides a
prototype for the usleep() function. Otherwise, it is up to the
program to supply one. A good guess is
extern int usleep(useconds_t);
"I_TIME"
This symbol is always defined, and indicates to the C program that
it should include time.h.
#ifdef I_TIME
#include <time.h>
#endif
"I_UTIME"
This symbol, if defined, indicates to the C program that it should
include utime.h.
#ifdef I_UTIME
#include <utime.h>
#endif
"LOCALTIME_MAX"
This symbol contains the maximum value for the "time_t" offset that
the system function localtime () accepts, and defaults to 0
"LOCALTIME_MIN"
This symbol contains the minimum value for the "time_t" offset that
the system function localtime () accepts, and defaults to 0
"LOCALTIME_R_NEEDS_TZSET"
Many libc's "localtime_r" implementations do not call tzset, making
them differ from localtime(), and making timezone changes using
$"ENV"{TZ} without explicitly calling tzset impossible. This symbol
makes us call tzset before "localtime_r"
"LOCALTIME_R_PROTO"
This symbol encodes the prototype of "localtime_r". It is zero if
"d_localtime_r" is undef, and one of the "REENTRANT_PROTO_T_ABC"
macros of reentr.h if "d_localtime_r" is defined.
"L_R_TZSET"
If localtime_r() needs tzset, it is defined in this define
"mini_mktime"
normalise "struct tm" values without the localtime() semantics (and
overhead) of mktime().
void mini_mktime(struct tm *ptm)
"sv_strftime_tm"
"my_strftime"
These implement the libc strftime().
On failure, they return NULL, and set "errno" to "EINVAL".
"sv_strftime_tm" is preferred, as it transparently handles the
UTF-8ness of the current locale, the input "fmt", and the returned
result. Only if the current "LC_TIME" locale is a UTF-8 one (and
"use bytes" is not in effect) will the result be marked as UTF-8.
"sv_strftime_tm" takes a pointer to a filled-in "struct tm"
parameter. It ignores the values of the "wday" and "yday" fields in
it. The other fields give enough information to accurately
calculate these values, and are used for that purpose.
The caller assumes ownership of the returned SV with a reference
count of 1.
"my_strftime" is kept for backwards compatibility. Knowing if its
result should be considered UTF-8 or not requires significant extra
logic.
The return value is a pointer to the formatted result (which MUST be
arranged to be FREED BY THE CALLER). This allows this function to
increase the buffer size as needed, so that the caller doesn't have
to worry about that, unlike libc strftime().
The "wday", "yday", and "isdst" parameters are ignored by
"my_strftime". Daylight savings time is never considered to exist,
and the values returned for the other two fields (if "fmt" even
calls for them) are calculated from the other parameters, without
need for referencing these.
Note that both functions are always executed in the underlying
"LC_TIME" locale of the program, giving results based on that
locale.
SV * sv_strftime_tm(SV *fmt, const struct tm *mytm)
char * my_strftime (const char *fmt, int sec, int min,
int hour, int mday, int mon, int year,
int wday, int yday, int isdst)
Typedef names
"DB_Hash_t"
This symbol contains the type of the prefix structure element in the
db.h header file. In older versions of DB, it was int, while in
newer ones it is "size_t".
"DB_Prefix_t"
This symbol contains the type of the prefix structure element in the
db.h header file. In older versions of DB, it was int, while in
newer ones it is "u_int32_t".
"Direntry_t"
This symbol is set to '"struct direct"' or '"struct dirent"'
depending on whether dirent is available or not. You should use this
pseudo type to portably declare your directory entries.
"Fpos_t"
This symbol holds the type used to declare file positions in libc.
It can be "fpos_t", long, uint, etc... It may be necessary to
include sys/types.h to get any typedef'ed information.
"Free_t"
This variable contains the return type of free(). It is usually
void, but occasionally int.
"Gid_t"
This symbol holds the return type of getgid() and the type of
argument to setrgid() and related functions. Typically, it is the
type of group ids in the kernel. It can be int, ushort, "gid_t",
etc... It may be necessary to include sys/types.h to get any
typedef'ed information.
"Gid_t_f"
This symbol defines the format string used for printing a "Gid_t".
"Gid_t_sign"
This symbol holds the signedness of a "Gid_t". 1 for unsigned, -1
for signed.
"Gid_t_size"
This symbol holds the size of a "Gid_t" in bytes.
"Groups_t"
This symbol holds the type used for the second argument to
getgroups() and setgroups(). Usually, this is the same as gidtype
("gid_t") , but sometimes it isn't. It can be int, ushort, "gid_t",
etc... It may be necessary to include sys/types.h to get any
typedef'ed information. This is only required if you have
getgroups() or setgroups()..
"Malloc_t"
This symbol is the type of pointer returned by malloc and realloc.
"Mmap_t"
This symbol holds the return type of the mmap() system call (and
simultaneously the type of the first argument). Usually set to
'void *' or '"caddr_t"'.
"Mode_t"
This symbol holds the type used to declare file modes for systems
calls. It is usually "mode_t", but may be int or unsigned short.
It may be necessary to include sys/types.h to get any typedef'ed
information.
"Netdb_hlen_t"
This symbol holds the type used for the 2nd argument to
gethostbyaddr().
"Netdb_host_t"
This symbol holds the type used for the 1st argument to
gethostbyaddr().
"Netdb_name_t"
This symbol holds the type used for the argument to gethostbyname().
"Netdb_net_t"
This symbol holds the type used for the 1st argument to
getnetbyaddr().
"Off_t"
This symbol holds the type used to declare offsets in the kernel.
It can be int, long, "off_t", etc... It may be necessary to include
sys/types.h to get any typedef'ed information.
"Off_t_size"
This symbol holds the number of bytes used by the "Off_t".
"Pid_t"
This symbol holds the type used to declare process ids in the
kernel. It can be int, uint, "pid_t", etc... It may be necessary to
include sys/types.h to get any typedef'ed information.
"Rand_seed_t"
This symbol defines the type of the argument of the random seed
function.
"Select_fd_set_t"
This symbol holds the type used for the 2nd, 3rd, and 4th arguments
to select. Usually, this is '"fd_set" *', if "HAS_FD_SET" is
defined, and 'int *' otherwise. This is only useful if you have
select(), of course.
"Shmat_t"
This symbol holds the return type of the shmat() system call.
Usually set to 'void *' or 'char *'.
"Signal_t"
This symbol's value is either "void" or "int", corresponding to the
appropriate return type of a signal handler. Thus, you can declare
a signal handler using ""Signal_t" (*handler)()", and define the
handler using ""Signal_t" handler(sig)".
"Size_t"
This symbol holds the type used to declare length parameters for
string functions. It is usually "size_t", but may be unsigned long,
int, etc. It may be necessary to include sys/types.h to get any
typedef'ed information.
"Size_t_size"
This symbol holds the size of a "Size_t" in bytes.
"Sock_size_t"
This symbol holds the type used for the size argument of various
socket calls (just the base type, not the pointer-to).
"SSize_t"
This symbol holds the type used by functions that return a count of
bytes or an error condition. It must be a signed type. It is
usually "ssize_t", but may be long or int, etc. It may be necessary
to include sys/types.h or unistd.h to get any typedef'ed
information. We will pick a type such that sizeof(SSize_t) ==
sizeof(Size_t).
"Time_t"
This symbol holds the type returned by time(). It can be long, or
"time_t" on "BSD" sites (in which case sys/types.h should be
included).
"Uid_t"
This symbol holds the type used to declare user ids in the kernel.
It can be int, ushort, "uid_t", etc... It may be necessary to
include sys/types.h to get any typedef'ed information.
"Uid_t_f"
This symbol defines the format string used for printing a "Uid_t".
"Uid_t_sign"
This symbol holds the signedness of a "Uid_t". 1 for unsigned, -1
for signed.
"Uid_t_size"
This symbol holds the size of a "Uid_t" in bytes.
Unicode Support
"Unicode Support" in perlguts has an introduction to this API.
See also "Character classification", "Character case changing", and
"String Handling". Various functions outside this section also work
specially with Unicode. Search for the string "utf8" in this document.
"BOM_UTF8"
This is a macro that evaluates to a string constant of the UTF-8
bytes that define the Unicode BYTE ORDER MARK (U+FEFF) for the
platform that perl is compiled on. This allows code to use a
mnemonic for this character that works on both ASCII and EBCDIC
platforms. "sizeof(BOM_UTF8) - 1" can be used to get its length in
bytes.
"bytes_cmp_utf8"
Compares the sequence of characters (stored as octets) in "b",
"blen" with the sequence of characters (stored as UTF-8) in "u",
"ulen". Returns 0 if they are equal, -1 or -2 if the first string
is less than the second string, +1 or +2 if the first string is
greater than the second string.
-1 or +1 is returned if the shorter string was identical to the
start of the longer string. -2 or +2 is returned if there was a
difference between characters within the strings.
int bytes_cmp_utf8(const U8 *b, STRLEN blen, const U8 *u,
STRLEN ulen)
"bytes_from_utf8"
NOTE: "bytes_from_utf8" is experimental and may change or be removed
without notice.
Converts a potentially UTF-8 encoded string "s" of length *lenp into
native byte encoding. On input, the boolean *is_utf8p gives whether
or not "s" is actually encoded in UTF-8.
Unlike "utf8_to_bytes" but like "bytes_to_utf8", this is non-
destructive of the input string.
Do nothing if *is_utf8p is 0, or if there are code points in the
string not expressible in native byte encoding. In these cases,
*is_utf8p and *lenp are unchanged, and the return value is the
original "s".
Otherwise, *is_utf8p is set to 0, and the return value is a pointer
to a newly created string containing a downgraded copy of "s", and
whose length is returned in *lenp, updated. The new string is
"NUL"-terminated. The caller is responsible for arranging for the
memory used by this string to get freed.
Upon successful return, the number of variants in the string can be
computed by having saved the value of *lenp before the call, and
subtracting the after-call value of *lenp from it.
U8 * bytes_from_utf8(const U8 *s, STRLEN *lenp, bool *is_utf8p)
"bytes_to_utf8"
NOTE: "bytes_to_utf8" is experimental and may change or be removed
without notice.
Converts a string "s" of length *lenp bytes from the native encoding
into UTF-8. Returns a pointer to the newly-created string, and sets
*lenp to reflect the new length in bytes. The caller is responsible
for arranging for the memory used by this string to get freed.
Upon successful return, the number of variants in the string can be
computed by having saved the value of *lenp before the call, and
subtracting it from the after-call value of *lenp.
A "NUL" character will be written after the end of the string.
If you want to convert to UTF-8 from encodings other than the native
(Latin1 or EBCDIC), see "sv_recode_to_utf8"().
U8 * bytes_to_utf8(const U8 *s, STRLEN *lenp)
"DO_UTF8"
Returns a bool giving whether or not the PV in "sv" is to be treated
as being encoded in UTF-8.
You should use this after a call to SvPV() or one of its variants,
in case any call to string overloading updates the internal UTF-8
encoding flag.
bool DO_UTF8(SV* sv)
"foldEQ_utf8"
Returns true if the leading portions of the strings "s1" and "s2"
(either or both of which may be in UTF-8) are the same case-
insensitively; false otherwise. How far into the strings to compare
is determined by other input parameters.
If "u1" is true, the string "s1" is assumed to be in UTF-8-encoded
Unicode; otherwise it is assumed to be in native 8-bit encoding.
Correspondingly for "u2" with respect to "s2".
If the byte length "l1" is non-zero, it says how far into "s1" to
check for fold equality. In other words, "s1"+"l1" will be used as
a goal to reach. The scan will not be considered to be a match
unless the goal is reached, and scanning won't continue past that
goal. Correspondingly for "l2" with respect to "s2".
If "pe1" is non-"NULL" and the pointer it points to is not "NULL",
that pointer is considered an end pointer to the position 1 byte
past the maximum point in "s1" beyond which scanning will not
continue under any circumstances. (This routine assumes that UTF-8
encoded input strings are not malformed; malformed input can cause
it to read past "pe1"). This means that if both "l1" and "pe1" are
specified, and "pe1" is less than "s1"+"l1", the match will never be
successful because it can never get as far as its goal (and in fact
is asserted against). Correspondingly for "pe2" with respect to
"s2".
At least one of "s1" and "s2" must have a goal (at least one of "l1"
and "l2" must be non-zero), and if both do, both have to be reached
for a successful match. Also, if the fold of a character is
multiple characters, all of them must be matched (see tr21 reference
below for 'folding').
Upon a successful match, if "pe1" is non-"NULL", it will be set to
point to the beginning of the next character of "s1" beyond what was
matched. Correspondingly for "pe2" and "s2".
For case-insensitiveness, the "casefolding" of Unicode is used
instead of upper/lowercasing both the characters, see
<https://www.unicode.org/reports/tr21/> (Case Mappings).
I32 foldEQ_utf8(const char *s1, char **pe1, UV l1, bool u1,
const char *s2, char **pe2, UV l2, bool u2)
"is_ascii_string"
This is a misleadingly-named synonym for "is_utf8_invariant_string".
On ASCII-ish platforms, the name isn't misleading: the ASCII-range
characters are exactly the UTF-8 invariants. But EBCDIC machines
have more invariants than just the ASCII characters, so
"is_utf8_invariant_string" is preferred.
bool is_ascii_string(const U8 * const s, STRLEN len)
"isC9_STRICT_UTF8_CHAR"
Evaluates to non-zero if the first few bytes of the string starting
at "s" and looking no further than "e - 1" are well-formed UTF-8
that represents some Unicode non-surrogate code point; otherwise it
evaluates to 0. If non-zero, the value gives how many bytes
starting at "s" comprise the code point's representation. Any bytes
remaining before "e", but beyond the ones needed to form the first
code point in "s", are not examined.
The largest acceptable code point is the Unicode maximum 0x10FFFF.
This differs from "isSTRICT_UTF8_CHAR" only in that it accepts non-
character code points. This corresponds to Unicode Corrigendum #9
<http://www.unicode.org/versions/corrigendum9.html>. which said
that non-character code points are merely discouraged rather than
completely forbidden in open interchange. See "Noncharacter code
points" in perlunicode.
Use "isUTF8_CHAR" to check for Perl's extended UTF-8; and
"isUTF8_CHAR_flags" for a more customized definition.
Use "is_c9strict_utf8_string", "is_c9strict_utf8_string_loc", and
"is_c9strict_utf8_string_loclen" to check entire strings.
Size_t isC9_STRICT_UTF8_CHAR(const U8 * const s0,
const U8 * const e)
"is_c9strict_utf8_string"
Returns TRUE if the first "len" bytes of string "s" form a valid
UTF-8-encoded string that conforms to Unicode Corrigendum #9
<http://www.unicode.org/versions/corrigendum9.html>; otherwise it
returns FALSE. If "len" is 0, it will be calculated using strlen(s)
(which means if you use this option, that "s" can't have embedded
"NUL" characters and has to have a terminating "NUL" byte). Note
that all characters being ASCII constitute 'a valid UTF-8 string'.
This function returns FALSE for strings containing any code points
above the Unicode max of 0x10FFFF or surrogate code points, but
accepts non-character code points per Corrigendum #9
<http://www.unicode.org/versions/corrigendum9.html>.
See also "is_utf8_invariant_string", "is_utf8_invariant_string_loc",
"is_utf8_string", "is_utf8_string_flags", "is_utf8_string_loc",
"is_utf8_string_loc_flags", "is_utf8_string_loclen",
"is_utf8_string_loclen_flags", "is_utf8_fixed_width_buf_flags",
"is_utf8_fixed_width_buf_loc_flags",
"is_utf8_fixed_width_buf_loclen_flags", "is_strict_utf8_string",
"is_strict_utf8_string_loc", "is_strict_utf8_string_loclen",
"is_c9strict_utf8_string_loc", and "is_c9strict_utf8_string_loclen".
bool is_c9strict_utf8_string(const U8 *s, STRLEN len)
"is_c9strict_utf8_string_loc"
Like "is_c9strict_utf8_string" but stores the location of the
failure (in the case of "utf8ness failure") or the location
"s"+"len" (in the case of "utf8ness success") in the "ep" pointer.
See also "is_c9strict_utf8_string_loclen".
bool is_c9strict_utf8_string_loc(const U8 *s, STRLEN len,
const U8 **ep)
"is_c9strict_utf8_string_loclen"
Like "is_c9strict_utf8_string" but stores the location of the
failure (in the case of "utf8ness failure") or the location
"s"+"len" (in the case of "utf8ness success") in the "ep" pointer,
and the number of UTF-8 encoded characters in the "el" pointer.
See also "is_c9strict_utf8_string_loc".
bool is_c9strict_utf8_string_loclen(const U8 *s, STRLEN len,
const U8 **ep, STRLEN *el)
"is_invariant_string"
This is a somewhat misleadingly-named synonym for
"is_utf8_invariant_string". "is_utf8_invariant_string" is
preferred, as it indicates under what conditions the string is
invariant.
bool is_invariant_string(const U8 * const s, STRLEN len)
"isSTRICT_UTF8_CHAR"
Evaluates to non-zero if the first few bytes of the string starting
at "s" and looking no further than "e - 1" are well-formed UTF-8
that represents some Unicode code point completely acceptable for
open interchange between all applications; otherwise it evaluates to
0. If non-zero, the value gives how many bytes starting at "s"
comprise the code point's representation. Any bytes remaining
before "e", but beyond the ones needed to form the first code point
in "s", are not examined.
The largest acceptable code point is the Unicode maximum 0x10FFFF,
and must not be a surrogate nor a non-character code point. Thus
this excludes any code point from Perl's extended UTF-8.
This is used to efficiently decide if the next few bytes in "s" is
legal Unicode-acceptable UTF-8 for a single character.
Use "isC9_STRICT_UTF8_CHAR" to use the Unicode Corrigendum #9
<http://www.unicode.org/versions/corrigendum9.html> definition of
allowable code points; "isUTF8_CHAR" to check for Perl's extended
UTF-8; and "isUTF8_CHAR_flags" for a more customized definition.
Use "is_strict_utf8_string", "is_strict_utf8_string_loc", and
"is_strict_utf8_string_loclen" to check entire strings.
Size_t isSTRICT_UTF8_CHAR(const U8 * const s0,
const U8 * const e)
"is_strict_utf8_string"
Returns TRUE if the first "len" bytes of string "s" form a valid
UTF-8-encoded string that is fully interchangeable by any
application using Unicode rules; otherwise it returns FALSE. If
"len" is 0, it will be calculated using strlen(s) (which means if
you use this option, that "s" can't have embedded "NUL" characters
and has to have a terminating "NUL" byte). Note that all characters
being ASCII constitute 'a valid UTF-8 string'.
This function returns FALSE for strings containing any code points
above the Unicode max of 0x10FFFF, surrogate code points, or non-
character code points.
See also "is_utf8_invariant_string", "is_utf8_invariant_string_loc",
"is_utf8_string", "is_utf8_string_flags", "is_utf8_string_loc",
"is_utf8_string_loc_flags", "is_utf8_string_loclen",
"is_utf8_string_loclen_flags", "is_utf8_fixed_width_buf_flags",
"is_utf8_fixed_width_buf_loc_flags",
"is_utf8_fixed_width_buf_loclen_flags", "is_strict_utf8_string_loc",
"is_strict_utf8_string_loclen", "is_c9strict_utf8_string",
"is_c9strict_utf8_string_loc", and "is_c9strict_utf8_string_loclen".
bool is_strict_utf8_string(const U8 *s, STRLEN len)
"is_strict_utf8_string_loc"
Like "is_strict_utf8_string" but stores the location of the failure
(in the case of "utf8ness failure") or the location "s"+"len" (in
the case of "utf8ness success") in the "ep" pointer.
See also "is_strict_utf8_string_loclen".
bool is_strict_utf8_string_loc(const U8 *s, STRLEN len,
const U8 **ep)
"is_strict_utf8_string_loclen"
Like "is_strict_utf8_string" but stores the location of the failure
(in the case of "utf8ness failure") or the location "s"+"len" (in
the case of "utf8ness success") in the "ep" pointer, and the number
of UTF-8 encoded characters in the "el" pointer.
See also "is_strict_utf8_string_loc".
bool is_strict_utf8_string_loclen(const U8 *s, STRLEN len,
const U8 **ep, STRLEN *el)
"isUTF8_CHAR"
Evaluates to non-zero if the first few bytes of the string starting
at "s" and looking no further than "e - 1" are well-formed UTF-8, as
extended by Perl, that represents some code point; otherwise it
evaluates to 0. If non-zero, the value gives how many bytes
starting at "s" comprise the code point's representation. Any bytes
remaining before "e", but beyond the ones needed to form the first
code point in "s", are not examined.
The code point can be any that will fit in an IV on this machine,
using Perl's extension to official UTF-8 to represent those higher
than the Unicode maximum of 0x10FFFF. That means that this macro is
used to efficiently decide if the next few bytes in "s" is legal
UTF-8 for a single character.
Use "isSTRICT_UTF8_CHAR" to restrict the acceptable code points to
those defined by Unicode to be fully interchangeable across
applications; "isC9_STRICT_UTF8_CHAR" to use the Unicode Corrigendum
#9 <http://www.unicode.org/versions/corrigendum9.html> definition of
allowable code points; and "isUTF8_CHAR_flags" for a more customized
definition.
Use "is_utf8_string", "is_utf8_string_loc", and
"is_utf8_string_loclen" to check entire strings.
Note also that a UTF-8 "invariant" character (i.e. ASCII on non-
EBCDIC machines) is a valid UTF-8 character.
Size_t isUTF8_CHAR(const U8 * const s0, const U8 * const e)
"is_utf8_char_buf"
This is identical to the macro "isUTF8_CHAR" in perlapi.
STRLEN is_utf8_char_buf(const U8 *buf, const U8 *buf_end)
"isUTF8_CHAR_flags"
Evaluates to non-zero if the first few bytes of the string starting
at "s" and looking no further than "e - 1" are well-formed UTF-8, as
extended by Perl, that represents some code point, subject to the
restrictions given by "flags"; otherwise it evaluates to 0. If non-
zero, the value gives how many bytes starting at "s" comprise the
code point's representation. Any bytes remaining before "e", but
beyond the ones needed to form the first code point in "s", are not
examined.
If "flags" is 0, this gives the same results as "isUTF8_CHAR"; if
"flags" is "UTF8_DISALLOW_ILLEGAL_INTERCHANGE", this gives the same
results as "isSTRICT_UTF8_CHAR"; and if "flags" is
"UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE", this gives the same results
as "isC9_STRICT_UTF8_CHAR". Otherwise "flags" may be any
combination of the "UTF8_DISALLOW_foo" flags understood by
"utf8n_to_uvchr", with the same meanings.
The three alternative macros are for the most commonly needed
validations; they are likely to run somewhat faster than this more
general one, as they can be inlined into your code.
Use "is_utf8_string_flags", "is_utf8_string_loc_flags", and
"is_utf8_string_loclen_flags" to check entire strings.
Size_t isUTF8_CHAR_flags(const U8 * const s0, const U8 * const e,
const U32 flags)
"is_utf8_fixed_width_buf_flags"
Returns TRUE if the fixed-width buffer starting at "s" with length
"len" is entirely valid UTF-8, subject to the restrictions given by
"flags"; otherwise it returns FALSE.
If "flags" is 0, any well-formed UTF-8, as extended by Perl, is
accepted without restriction. If the final few bytes of the buffer
do not form a complete code point, this will return TRUE anyway,
provided that "is_utf8_valid_partial_char_flags" returns TRUE for
them.
If "flags" in non-zero, it can be any combination of the
"UTF8_DISALLOW_foo" flags accepted by "utf8n_to_uvchr", and with the
same meanings.
This function differs from "is_utf8_string_flags" only in that the
latter returns FALSE if the final few bytes of the string don't form
a complete code point.
bool is_utf8_fixed_width_buf_flags(const U8 * const s,
STRLEN len, const U32 flags)
"is_utf8_fixed_width_buf_loc_flags"
Like "is_utf8_fixed_width_buf_flags" but stores the location of the
failure in the "ep" pointer. If the function returns TRUE, *ep will
point to the beginning of any partial character at the end of the
buffer; if there is no partial character *ep will contain "s"+"len".
See also "is_utf8_fixed_width_buf_loclen_flags".
bool is_utf8_fixed_width_buf_loc_flags(const U8 * const s,
STRLEN len, const U8 **ep,
const U32 flags)
"is_utf8_fixed_width_buf_loclen_flags"
Like "is_utf8_fixed_width_buf_loc_flags" but stores the number of
complete, valid characters found in the "el" pointer.
bool is_utf8_fixed_width_buf_loclen_flags(const U8 * const s,
STRLEN len,
const U8 **ep,
STRLEN *el,
const U32 flags)
"is_utf8_invariant_string"
Returns TRUE if the first "len" bytes of the string "s" are the same
regardless of the UTF-8 encoding of the string (or UTF-EBCDIC
encoding on EBCDIC machines); otherwise it returns FALSE. That is,
it returns TRUE if they are UTF-8 invariant. On ASCII-ish machines,
all the ASCII characters and only the ASCII characters fit this
definition. On EBCDIC machines, the ASCII-range characters are
invariant, but so also are the C1 controls.
If "len" is 0, it will be calculated using strlen(s), (which means
if you use this option, that "s" can't have embedded "NUL"
characters and has to have a terminating "NUL" byte).
See also "is_utf8_string", "is_utf8_string_flags",
"is_utf8_string_loc", "is_utf8_string_loc_flags",
"is_utf8_string_loclen", "is_utf8_string_loclen_flags",
"is_utf8_fixed_width_buf_flags",
"is_utf8_fixed_width_buf_loc_flags",
"is_utf8_fixed_width_buf_loclen_flags", "is_strict_utf8_string",
"is_strict_utf8_string_loc", "is_strict_utf8_string_loclen",
"is_c9strict_utf8_string", "is_c9strict_utf8_string_loc", and
"is_c9strict_utf8_string_loclen".
bool is_utf8_invariant_string(const U8 * const s, STRLEN len)
"is_utf8_invariant_string_loc"
Like "is_utf8_invariant_string" but upon failure, stores the
location of the first UTF-8 variant character in the "ep" pointer;
if all characters are UTF-8 invariant, this function does not change
the contents of *ep.
bool is_utf8_invariant_string_loc(const U8 * const s, STRLEN len,
const U8 **ep)
"is_utf8_string"
Returns TRUE if the first "len" bytes of string "s" form a valid
Perl-extended-UTF-8 string; returns FALSE otherwise. If "len" is 0,
it will be calculated using strlen(s) (which means if you use this
option, that "s" can't have embedded "NUL" characters and has to
have a terminating "NUL" byte). Note that all characters being
ASCII constitute 'a valid UTF-8 string'.
This function considers Perl's extended UTF-8 to be valid. That
means that code points above Unicode, surrogates, and non-character
code points are considered valid by this function. Use
"is_strict_utf8_string", "is_c9strict_utf8_string", or
"is_utf8_string_flags" to restrict what code points are considered
valid.
See also "is_utf8_invariant_string", "is_utf8_invariant_string_loc",
"is_utf8_string_loc", "is_utf8_string_loclen",
"is_utf8_fixed_width_buf_flags",
"is_utf8_fixed_width_buf_loc_flags",
"is_utf8_fixed_width_buf_loclen_flags",
bool is_utf8_string(const U8 *s, STRLEN len)
"is_utf8_string_flags"
Returns TRUE if the first "len" bytes of string "s" form a valid
UTF-8 string, subject to the restrictions imposed by "flags";
returns FALSE otherwise. If "len" is 0, it will be calculated using
strlen(s) (which means if you use this option, that "s" can't have
embedded "NUL" characters and has to have a terminating "NUL" byte).
Note that all characters being ASCII constitute 'a valid UTF-8
string'.
If "flags" is 0, this gives the same results as "is_utf8_string"; if
"flags" is "UTF8_DISALLOW_ILLEGAL_INTERCHANGE", this gives the same
results as "is_strict_utf8_string"; and if "flags" is
"UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE", this gives the same results
as "is_c9strict_utf8_string". Otherwise "flags" may be any
combination of the "UTF8_DISALLOW_foo" flags understood by
"utf8n_to_uvchr", with the same meanings.
See also "is_utf8_invariant_string", "is_utf8_invariant_string_loc",
"is_utf8_string", "is_utf8_string_loc", "is_utf8_string_loc_flags",
"is_utf8_string_loclen", "is_utf8_string_loclen_flags",
"is_utf8_fixed_width_buf_flags",
"is_utf8_fixed_width_buf_loc_flags",
"is_utf8_fixed_width_buf_loclen_flags", "is_strict_utf8_string",
"is_strict_utf8_string_loc", "is_strict_utf8_string_loclen",
"is_c9strict_utf8_string", "is_c9strict_utf8_string_loc", and
"is_c9strict_utf8_string_loclen".
bool is_utf8_string_flags(const U8 *s, STRLEN len,
const U32 flags)
"is_utf8_string_loc"
Like "is_utf8_string" but stores the location of the failure (in the
case of "utf8ness failure") or the location "s"+"len" (in the case
of "utf8ness success") in the "ep" pointer.
See also "is_utf8_string_loclen".
bool is_utf8_string_loc(const U8 *s, const STRLEN len,
const U8 **ep)
"is_utf8_string_loc_flags"
Like "is_utf8_string_flags" but stores the location of the failure
(in the case of "utf8ness failure") or the location "s"+"len" (in
the case of "utf8ness success") in the "ep" pointer.
See also "is_utf8_string_loclen_flags".
bool is_utf8_string_loc_flags(const U8 *s, STRLEN len,
const U8 **ep, const U32 flags)
"is_utf8_string_loclen"
Like "is_utf8_string" but stores the location of the failure (in the
case of "utf8ness failure") or the location "s"+"len" (in the case
of "utf8ness success") in the "ep" pointer, and the number of UTF-8
encoded characters in the "el" pointer.
See also "is_utf8_string_loc".
bool is_utf8_string_loclen(const U8 *s, STRLEN len,
const U8 **ep, STRLEN *el)
"is_utf8_string_loclen_flags"
Like "is_utf8_string_flags" but stores the location of the failure
(in the case of "utf8ness failure") or the location "s"+"len" (in
the case of "utf8ness success") in the "ep" pointer, and the number
of UTF-8 encoded characters in the "el" pointer.
See also "is_utf8_string_loc_flags".
bool is_utf8_string_loclen_flags(const U8 *s, STRLEN len,
const U8 **ep, STRLEN *el,
const U32 flags)
"is_utf8_valid_partial_char"
Returns 0 if the sequence of bytes starting at "s" and looking no
further than "e - 1" is the UTF-8 encoding, as extended by Perl, for
one or more code points. Otherwise, it returns 1 if there exists at
least one non-empty sequence of bytes that when appended to sequence
"s", starting at position "e" causes the entire sequence to be the
well-formed UTF-8 of some code point; otherwise returns 0.
In other words this returns TRUE if "s" points to a partial
UTF-8-encoded code point.
This is useful when a fixed-length buffer is being tested for being
well-formed UTF-8, but the final few bytes in it don't comprise a
full character; that is, it is split somewhere in the middle of the
final code point's UTF-8 representation. (Presumably when the
buffer is refreshed with the next chunk of data, the new first bytes
will complete the partial code point.) This function is used to
verify that the final bytes in the current buffer are in fact the
legal beginning of some code point, so that if they aren't, the
failure can be signalled without having to wait for the next read.
bool is_utf8_valid_partial_char(const U8 * const s0,
const U8 * const e)
"is_utf8_valid_partial_char_flags"
Like "is_utf8_valid_partial_char", it returns a boolean giving
whether or not the input is a valid UTF-8 encoded partial character,
but it takes an extra parameter, "flags", which can further restrict
which code points are considered valid.
If "flags" is 0, this behaves identically to
"is_utf8_valid_partial_char". Otherwise "flags" can be any
combination of the "UTF8_DISALLOW_foo" flags accepted by
"utf8n_to_uvchr". If there is any sequence of bytes that can
complete the input partial character in such a way that a non-
prohibited character is formed, the function returns TRUE; otherwise
FALSE. Non character code points cannot be determined based on
partial character input. But many of the other possible excluded
types can be determined from just the first one or two bytes.
bool is_utf8_valid_partial_char_flags(const U8 * const s0,
const U8 * const e,
const U32 flags)
"LATIN1_TO_NATIVE"
Returns the native equivalent of the input Latin-1 code point
(including ASCII and control characters) given by "ch". Thus,
LATIN1_TO_NATIVE(66) on EBCDIC platforms returns 194. These each
represent the character "B" on their respective platforms. On ASCII
platforms no conversion is needed, so this macro expands to just its
input, adding no time nor space requirements to the implementation.
For conversion of code points potentially larger than will fit in a
character, use "UNI_TO_NATIVE".
U8 LATIN1_TO_NATIVE(U8 ch)
"NATIVE_TO_LATIN1"
Returns the Latin-1 (including ASCII and control characters)
equivalent of the input native code point given by "ch". Thus,
NATIVE_TO_LATIN1(193) on EBCDIC platforms returns 65. These each
represent the character "A" on their respective platforms. On ASCII
platforms no conversion is needed, so this macro expands to just its
input, adding no time nor space requirements to the implementation.
For conversion of code points potentially larger than will fit in a
character, use "NATIVE_TO_UNI".
U8 NATIVE_TO_LATIN1(U8 ch)
"NATIVE_TO_UNI"
Returns the Unicode equivalent of the input native code point given
by "ch". Thus, NATIVE_TO_UNI(195) on EBCDIC platforms returns 67.
These each represent the character "C" on their respective
platforms. On ASCII platforms no conversion is needed, so this
macro expands to just its input, adding no time nor space
requirements to the implementation.
UV NATIVE_TO_UNI(UV ch)
"pv_uni_display"
Build to the scalar "dsv" a displayable version of the UTF-8 encoded
string "spv", length "len", the displayable version being at most
"pvlim" bytes long (if longer, the rest is truncated and "..." will
be appended).
The "flags" argument can have "UNI_DISPLAY_ISPRINT" set to display
isPRINT()able characters as themselves, "UNI_DISPLAY_BACKSLASH" to
display the "\\[nrfta\\]" as the backslashed versions (like "\n")
("UNI_DISPLAY_BACKSLASH" is preferred over "UNI_DISPLAY_ISPRINT" for
"\\"). "UNI_DISPLAY_QQ" (and its alias "UNI_DISPLAY_REGEX") have
both "UNI_DISPLAY_BACKSLASH" and "UNI_DISPLAY_ISPRINT" turned on.
Additionally, there is now "UNI_DISPLAY_BACKSPACE" which allows "\b"
for a backspace, but only when "UNI_DISPLAY_BACKSLASH" also is set.
The pointer to the PV of the "dsv" is returned.
See also "sv_uni_display".
char * pv_uni_display(SV *dsv, const U8 *spv, STRLEN len,
STRLEN pvlim, UV flags)
"REPLACEMENT_CHARACTER_UTF8"
This is a macro that evaluates to a string constant of the UTF-8
bytes that define the Unicode REPLACEMENT CHARACTER (U+FFFD) for the
platform that perl is compiled on. This allows code to use a
mnemonic for this character that works on both ASCII and EBCDIC
platforms. "sizeof(REPLACEMENT_CHARACTER_UTF8) - 1" can be used to
get its length in bytes.
"sv_cat_decode"
"encoding" is assumed to be an "Encode" object, the PV of "ssv" is
assumed to be octets in that encoding and decoding the input starts
from the position which "(PV + *offset)" pointed to. "dsv" will be
concatenated with the decoded UTF-8 string from "ssv". Decoding
will terminate when the string "tstr" appears in decoding output or
the input ends on the PV of "ssv". The value which "offset" points
will be modified to the last input position on "ssv".
Returns TRUE if the terminator was found, else returns FALSE.
bool sv_cat_decode(SV *dsv, SV *encoding, SV *ssv, int *offset,
char *tstr, int tlen)
"sv_recode_to_utf8"
"encoding" is assumed to be an "Encode" object, on entry the PV of
"sv" is assumed to be octets in that encoding, and "sv" will be
converted into Unicode (and UTF-8).
If "sv" already is UTF-8 (or if it is not "POK"), or if "encoding"
is not a reference, nothing is done to "sv". If "encoding" is not
an "Encode::XS" Encoding object, bad things will happen. (See
encoding and Encode.)
The PV of "sv" is returned.
char * sv_recode_to_utf8(SV *sv, SV *encoding)
"sv_uni_display"
Build to the scalar "dsv" a displayable version of the scalar "sv",
the displayable version being at most "pvlim" bytes long (if longer,
the rest is truncated and "..." will be appended).
The "flags" argument is as in "pv_uni_display"().
The pointer to the PV of the "dsv" is returned.
char * sv_uni_display(SV *dsv, SV *ssv, STRLEN pvlim, UV flags)
"UNICODE_IS_NONCHAR"
Returns a boolean as to whether or not "uv" is one of the Unicode
non-character code points
bool UNICODE_IS_NONCHAR(const UV uv)
"UNICODE_IS_REPLACEMENT"
Returns a boolean as to whether or not "uv" is the Unicode
REPLACEMENT CHARACTER
bool UNICODE_IS_REPLACEMENT(const UV uv)
"UNICODE_IS_SUPER"
Returns a boolean as to whether or not "uv" is above the maximum
legal Unicode code point of U+10FFFF.
bool UNICODE_IS_SUPER(const UV uv)
"UNICODE_IS_SURROGATE"
Returns a boolean as to whether or not "uv" is one of the Unicode
surrogate code points
bool UNICODE_IS_SURROGATE(const UV uv)
"UNICODE_REPLACEMENT"
Evaluates to 0xFFFD, the code point of the Unicode REPLACEMENT
CHARACTER
"UNI_TO_NATIVE"
Returns the native equivalent of the input Unicode code point
given by "ch". Thus, UNI_TO_NATIVE(68) on EBCDIC platforms returns
196. These each represent the character "D" on their respective
platforms. On ASCII platforms no conversion is needed, so this
macro expands to just its input, adding no time nor space
requirements to the implementation.
UV UNI_TO_NATIVE(UV ch)
"UTF8_CHK_SKIP"
This is a safer version of "UTF8SKIP", but still not as safe as
"UTF8_SAFE_SKIP". This version doesn't blindly assume that the
input string pointed to by "s" is well-formed, but verifies that
there isn't a NUL terminating character before the expected end of
the next character in "s". The length "UTF8_CHK_SKIP" returns stops
just before any such NUL.
Perl tends to add NULs, as an insurance policy, after the end of
strings in SV's, so it is likely that using this macro will prevent
inadvertent reading beyond the end of the input buffer, even if it
is malformed UTF-8.
This macro is intended to be used by XS modules where the inputs
could be malformed, and it isn't feasible to restructure to use the
safer "UTF8_SAFE_SKIP", for example when interfacing with a C
library.
STRLEN UTF8_CHK_SKIP(char* s)
"utf8_distance"
Returns the number of UTF-8 characters between the UTF-8 pointers
"a" and "b".
WARNING: use only if you *know* that the pointers point inside the
same UTF-8 buffer.
IV utf8_distance(const U8 *a, const U8 *b)
"utf8_hop"
Return the UTF-8 pointer "s" displaced by "off" characters, either
forward (if "off" is positive) or backward (if negative). "s" does
not need to be pointing to the starting byte of a character. If it
isn't, one count of "off" will be used up to get to the start of the
next character for forward hops, and to the start of the current
character for negative ones.
WARNING: Prefer "utf8_hop_safe" to this one.
Do NOT use this function unless you know "off" is within the UTF-8
data pointed to by "s" and that on entry "s" is aligned on the first
byte of a character or just after the last byte of a character.
U8 * utf8_hop(const U8 *s, SSize_t off)
"utf8_hop_back"
Return the UTF-8 pointer "s" displaced by up to "off" characters,
backward. "s" does not need to be pointing to the starting byte of
a character. If it isn't, one count of "off" will be used up to get
to that start.
"off" must be non-positive.
"s" must be after or equal to "start".
When moving backward it will not move before "start".
Will not exceed this limit even if the string is not valid "UTF-8".
U8 * utf8_hop_back(const U8 *s, SSize_t off, const U8 *start)
"utf8_hop_forward"
Return the UTF-8 pointer "s" displaced by up to "off" characters,
forward. "s" does not need to be pointing to the starting byte of a
character. If it isn't, one count of "off" will be used up to get
to the start of the next character.
"off" must be non-negative.
"s" must be before or equal to "end".
When moving forward it will not move beyond "end".
Will not exceed this limit even if the string is not valid "UTF-8".
U8 * utf8_hop_forward(const U8 *s, SSize_t off, const U8 *end)
"utf8_hop_safe"
Return the UTF-8 pointer "s" displaced by up to "off" characters,
either forward or backward. "s" does not need to be pointing to the
starting byte of a character. If it isn't, one count of "off" will
be used up to get to the start of the next character for forward
hops, and to the start of the current character for negative ones.
When moving backward it will not move before "start".
When moving forward it will not move beyond "end".
Will not exceed those limits even if the string is not valid
"UTF-8".
U8 * utf8_hop_safe(const U8 *s, SSize_t off, const U8 *start,
const U8 *end)
"UTF8_IS_INVARIANT"
Evaluates to 1 if the byte "c" represents the same character when
encoded in UTF-8 as when not; otherwise evaluates to 0. UTF-8
invariant characters can be copied as-is when converting to/from
UTF-8, saving time.
In spite of the name, this macro gives the correct result if the
input string from which "c" comes is not encoded in UTF-8.
See "UVCHR_IS_INVARIANT" for checking if a UV is invariant.
bool UTF8_IS_INVARIANT(char c)
"UTF8_IS_NONCHAR"
Evaluates to non-zero if the first few bytes of the string starting
at "s" and looking no further than "e - 1" are well-formed UTF-8
that represents one of the Unicode non-character code points;
otherwise it evaluates to 0. If non-zero, the value gives how many
bytes starting at "s" comprise the code point's representation.
bool UTF8_IS_NONCHAR(const U8 *s, const U8 *e)
"UTF8_IS_REPLACEMENT"
Evaluates to non-zero if the first few bytes of the string starting
at "s" and looking no further than "e - 1" are well-formed UTF-8
that represents the Unicode REPLACEMENT CHARACTER; otherwise it
evaluates to 0. If non-zero, the value gives how many bytes
starting at "s" comprise the code point's representation.
bool UTF8_IS_REPLACEMENT(const U8 *s, const U8 *e)
"UTF8_IS_SUPER"
Recall that Perl recognizes an extension to UTF-8 that can encode
code points larger than the ones defined by Unicode, which are
0..0x10FFFF.
This macro evaluates to non-zero if the first few bytes of the
string starting at "s" and looking no further than "e - 1" are from
this UTF-8 extension; otherwise it evaluates to 0. If non-zero, the
return is how many bytes starting at "s" comprise the code point's
representation.
0 is returned if the bytes are not well-formed extended UTF-8, or if
they represent a code point that cannot fit in a UV on the current
platform. Hence this macro can give different results when run on a
64-bit word machine than on one with a 32-bit word size.
Note that it is illegal in Perl to have code points that are larger
than what can fit in an IV on the current machine; and illegal in
Unicode to have any that this macro matches
bool UTF8_IS_SUPER(const U8 *s, const U8 *e)
"UTF8_IS_SURROGATE"
Evaluates to non-zero if the first few bytes of the string starting
at "s" and looking no further than "e - 1" are well-formed UTF-8
that represents one of the Unicode surrogate code points; otherwise
it evaluates to 0. If non-zero, the value gives how many bytes
starting at "s" comprise the code point's representation.
bool UTF8_IS_SURROGATE(const U8 *s, const U8 *e)
"utf8_length"
Returns the number of characters in the sequence of UTF-8-encoded
bytes starting at "s" and ending at the byte just before "e". If
<s> and <e> point to the same place, it returns 0 with no warning
raised.
If "e < s" or if the scan would end up past "e", it raises a UTF8
warning and returns the number of valid characters.
STRLEN utf8_length(const U8 *s0, const U8 *e)
"UTF8_MAXBYTES"
The maximum width of a single UTF-8 encoded character, in bytes.
NOTE: Strictly speaking Perl's UTF-8 should not be called UTF-8
since UTF-8 is an encoding of Unicode, and Unicode's upper limit,
0x10FFFF, can be expressed with 4 bytes. However, Perl thinks of
UTF-8 as a way to encode non-negative integers in a binary format,
even those above Unicode.
"UTF8_MAXBYTES_CASE"
The maximum number of UTF-8 bytes a single Unicode character can
uppercase/lowercase/titlecase/fold into.
"utf8ness_t"
This typedef is used by several core functions that return PV
strings, to indicate the UTF-8ness of those strings.
(If you write a new function, you probably should instead return the
PV in an SV with the UTF-8 flag of the SV properly set, rather than
use this mechanism.)
The possible values this can be are:
"UTF8NESS_YES"
This means the string definitely should be treated as a sequence
of UTF-8-encoded characters.
Most code that needs to handle this typedef should be of the
form:
if (utf8ness_flag == UTF8NESS_YES) {
treat as utf8; // like turning on an SV UTF-8 flag
}
"UTF8NESS_NO"
This means the string definitely should be treated as a sequence
of bytes, not encoded as UTF-8.
"UTF8NESS_IMMATERIAL"
This means it is equally valid to treat the string as bytes, or
as UTF-8 characters; use whichever way you want. This happens
when the string consists entirely of characters which have the
same representation whether encoded in UTF-8 or not.
"UTF8NESS_UNKNOWN"
This means it is unknown how the string should be treated. No
core function will ever return this value to a non-core caller.
Instead, it is used by the caller to initialize a variable to a
non-legal value. A typical call will look like:
utf8ness_t string_is_utf8 = UTF8NESS_UNKNOWN
const char * string = foo(arg1, arg2, ..., &string_is_utf8);
if (string_is_utf8 == UTF8NESS_YES) {
do something for UTF-8;
}
The following relationships hold between the enum values:
"0 <= enum value <= UTF8NESS_IMMATERIAL"
the string may be treated in code as non-UTF8
"UTF8NESS_IMMATERIAL <= <enum value"
the string may be treated in code as encoded in UTF-8
"utf8n_to_uvchr"
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
Most code should use "utf8_to_uvchr_buf"() rather than call this
directly.
Bottom level UTF-8 decode routine. Returns the native code point
value of the first character in the string "s", which is assumed to
be in UTF-8 (or UTF-EBCDIC) encoding, and no longer than "curlen"
bytes; *retlen (if "retlen" isn't NULL) will be set to the length,
in bytes, of that character.
The value of "flags" determines the behavior when "s" does not point
to a well-formed UTF-8 character. If "flags" is 0, encountering a
malformation causes zero to be returned and *retlen is set so that
("s" + *retlen) is the next possible position in "s" that could
begin a non-malformed character. Also, if UTF-8 warnings haven't
been lexically disabled, a warning is raised. Some UTF-8 input
sequences may contain multiple malformations. This function tries
to find every possible one in each call, so multiple warnings can be
raised for the same sequence.
Various ALLOW flags can be set in "flags" to allow (and not warn on)
individual types of malformations, such as the sequence being
overlong (that is, when there is a shorter sequence that can express
the same code point; overlong sequences are expressly forbidden in
the UTF-8 standard due to potential security issues). Another
malformation example is the first byte of a character not being a
legal first byte. See utf8.h for the list of such flags. Even if
allowed, this function generally returns the Unicode REPLACEMENT
CHARACTER when it encounters a malformation. There are flags in
utf8.h to override this behavior for the overlong malformations, but
don't do that except for very specialized purposes.
The "UTF8_CHECK_ONLY" flag overrides the behavior when a non-allowed
(by other flags) malformation is found. If this flag is set, the
routine assumes that the caller will raise a warning, and this
function will silently just set "retlen" to -1 (cast to "STRLEN")
and return zero.
Note that this API requires disambiguation between successful
decoding a "NUL" character, and an error return (unless the
"UTF8_CHECK_ONLY" flag is set), as in both cases, 0 is returned,
and, depending on the malformation, "retlen" may be set to 1. To
disambiguate, upon a zero return, see if the first byte of "s" is 0
as well. If so, the input was a "NUL"; if not, the input had an
error. Or you can use "utf8n_to_uvchr_error".
Certain code points are considered problematic. These are Unicode
surrogates, Unicode non-characters, and code points above the
Unicode maximum of 0x10FFFF. By default these are considered
regular code points, but certain situations warrant special handling
for them, which can be specified using the "flags" parameter. If
"flags" contains "UTF8_DISALLOW_ILLEGAL_INTERCHANGE", all three
classes are treated as malformations and handled as such. The flags
"UTF8_DISALLOW_SURROGATE", "UTF8_DISALLOW_NONCHAR", and
"UTF8_DISALLOW_SUPER" (meaning above the legal Unicode maximum) can
be set to disallow these categories individually.
"UTF8_DISALLOW_ILLEGAL_INTERCHANGE" restricts the allowed inputs to
the strict UTF-8 traditionally defined by Unicode. Use
"UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE" to use the strictness
definition given by Unicode Corrigendum #9
<https://www.unicode.org/versions/corrigendum9.html>. The
difference between traditional strictness and C9 strictness is that
the latter does not forbid non-character code points. (They are
still discouraged, however.) For more discussion see "Noncharacter
code points" in perlunicode.
The flags "UTF8_WARN_ILLEGAL_INTERCHANGE",
"UTF8_WARN_ILLEGAL_C9_INTERCHANGE", "UTF8_WARN_SURROGATE",
"UTF8_WARN_NONCHAR", and "UTF8_WARN_SUPER" will cause warning
messages to be raised for their respective categories, but otherwise
the code points are considered valid (not malformations). To get a
category to both be treated as a malformation and raise a warning,
specify both the WARN and DISALLOW flags. (But note that warnings
are not raised if lexically disabled nor if "UTF8_CHECK_ONLY" is
also specified.)
Extremely high code points were never specified in any standard, and
require an extension to UTF-8 to express, which Perl does. It is
likely that programs written in something other than Perl would not
be able to read files that contain these; nor would Perl understand
files written by something that uses a different extension. For
these reasons, there is a separate set of flags that can warn and/or
disallow these extremely high code points, even if other above-
Unicode ones are accepted. They are the "UTF8_WARN_PERL_EXTENDED"
and "UTF8_DISALLOW_PERL_EXTENDED" flags. For more information see
"UTF8_GOT_PERL_EXTENDED". Of course "UTF8_DISALLOW_SUPER" will
treat all above-Unicode code points, including these, as
malformations. (Note that the Unicode standard considers anything
above 0x10FFFF to be illegal, but there are standards predating it
that allow up to 0x7FFF_FFFF (2**31 -1))
A somewhat misleadingly named synonym for "UTF8_WARN_PERL_EXTENDED"
is retained for backward compatibility: "UTF8_WARN_ABOVE_31_BIT".
Similarly, "UTF8_DISALLOW_ABOVE_31_BIT" is usable instead of the
more accurately named "UTF8_DISALLOW_PERL_EXTENDED". The names are
misleading because these flags can apply to code points that
actually do fit in 31 bits. This happens on EBCDIC platforms, and
sometimes when the overlong malformation is also present. The new
names accurately describe the situation in all cases.
All other code points corresponding to Unicode characters, including
private use and those yet to be assigned, are never considered
malformed and never warn.
UV utf8n_to_uvchr(const U8 *s, STRLEN curlen, STRLEN *retlen,
const U32 flags)
"utf8n_to_uvchr_error"
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
Most code should use "utf8_to_uvchr_buf"() rather than call this
directly.
This function is for code that needs to know what the precise
malformation(s) are when an error is found. If you also need to
know the generated warning messages, use "utf8n_to_uvchr_msgs"()
instead.
It is like "utf8n_to_uvchr" but it takes an extra parameter placed
after all the others, "errors". If this parameter is 0, this
function behaves identically to "utf8n_to_uvchr". Otherwise,
"errors" should be a pointer to a "U32" variable, which this
function sets to indicate any errors found. Upon return, if *errors
is 0, there were no errors found. Otherwise, *errors is the bit-
wise "OR" of the bits described in the list below. Some of these
bits will be set if a malformation is found, even if the input
"flags" parameter indicates that the given malformation is allowed;
those exceptions are noted:
"UTF8_GOT_PERL_EXTENDED"
The input sequence is not standard UTF-8, but a Perl extension.
This bit is set only if the input "flags" parameter contains
either the "UTF8_DISALLOW_PERL_EXTENDED" or the
"UTF8_WARN_PERL_EXTENDED" flags.
Code points above 0x7FFF_FFFF (2**31 - 1) were never specified
in any standard, and so some extension must be used to express
them. Perl uses a natural extension to UTF-8 to represent the
ones up to 2**36-1, and invented a further extension to
represent even higher ones, so that any code point that fits in
a 64-bit word can be represented. Text using these extensions
is not likely to be portable to non-Perl code. We lump both of
these extensions together and refer to them as Perl extended
UTF-8. There exist other extensions that people have invented,
incompatible with Perl's.
On EBCDIC platforms starting in Perl v5.24, the Perl extension
for representing extremely high code points kicks in at
0x3FFF_FFFF (2**30 -1), which is lower than on ASCII. Prior to
that, code points 2**31 and higher were simply unrepresentable,
and a different, incompatible method was used to represent code
points between 2**30 and 2**31 - 1.
On both platforms, ASCII and EBCDIC, "UTF8_GOT_PERL_EXTENDED" is
set if Perl extended UTF-8 is used.
In earlier Perls, this bit was named "UTF8_GOT_ABOVE_31_BIT",
which you still may use for backward compatibility. That name
is misleading, as this flag may be set when the code point
actually does fit in 31 bits. This happens on EBCDIC platforms,
and sometimes when the overlong malformation is also present.
The new name accurately describes the situation in all cases.
"UTF8_GOT_CONTINUATION"
The input sequence was malformed in that the first byte was a
UTF-8 continuation byte.
"UTF8_GOT_EMPTY"
The input "curlen" parameter was 0.
"UTF8_GOT_LONG"
The input sequence was malformed in that there is some other
sequence that evaluates to the same code point, but that
sequence is shorter than this one.
Until Unicode 3.1, it was legal for programs to accept this
malformation, but it was discovered that this created security
issues.
"UTF8_GOT_NONCHAR"
The code point represented by the input UTF-8 sequence is for a
Unicode non-character code point. This bit is set only if the
input "flags" parameter contains either the
"UTF8_DISALLOW_NONCHAR" or the "UTF8_WARN_NONCHAR" flags.
"UTF8_GOT_NON_CONTINUATION"
The input sequence was malformed in that a non-continuation type
byte was found in a position where only a continuation type one
should be. See also "UTF8_GOT_SHORT".
"UTF8_GOT_OVERFLOW"
The input sequence was malformed in that it is for a code point
that is not representable in the number of bits available in an
IV on the current platform.
"UTF8_GOT_SHORT"
The input sequence was malformed in that "curlen" is smaller
than required for a complete sequence. In other words, the
input is for a partial character sequence.
"UTF8_GOT_SHORT" and "UTF8_GOT_NON_CONTINUATION" both indicate a
too short sequence. The difference is that
"UTF8_GOT_NON_CONTINUATION" indicates always that there is an
error, while "UTF8_GOT_SHORT" means that an incomplete sequence
was looked at. If no other flags are present, it means that
the sequence was valid as far as it went. Depending on the
application, this could mean one of three things:
• The "curlen" length parameter passed in was too small, and
the function was prevented from examining all the necessary
bytes.
• The buffer being looked at is based on reading data, and the
data received so far stopped in the middle of a character,
so that the next read will read the remainder of this
character. (It is up to the caller to deal with the split
bytes somehow.)
• This is a real error, and the partial sequence is all we're
going to get.
"UTF8_GOT_SUPER"
The input sequence was malformed in that it is for a non-Unicode
code point; that is, one above the legal Unicode maximum. This
bit is set only if the input "flags" parameter contains either
the "UTF8_DISALLOW_SUPER" or the "UTF8_WARN_SUPER" flags.
"UTF8_GOT_SURROGATE"
The input sequence was malformed in that it is for a -Unicode
UTF-16 surrogate code point. This bit is set only if the input
"flags" parameter contains either the "UTF8_DISALLOW_SURROGATE"
or the "UTF8_WARN_SURROGATE" flags.
To do your own error handling, call this function with the
"UTF8_CHECK_ONLY" flag to suppress any warnings, and then examine
the *errors return.
UV utf8n_to_uvchr_error(const U8 *s, STRLEN curlen,
STRLEN *retlen, const U32 flags,
U32 *errors)
"utf8n_to_uvchr_msgs"
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
Most code should use "utf8_to_uvchr_buf"() rather than call this
directly.
This function is for code that needs to know what the precise
malformation(s) are when an error is found, and wants the
corresponding warning and/or error messages to be returned to the
caller rather than be displayed. All messages that would have been
displayed if all lexical warnings are enabled will be returned.
It is just like "utf8n_to_uvchr_error" but it takes an extra
parameter placed after all the others, "msgs". If this parameter is
0, this function behaves identically to "utf8n_to_uvchr_error".
Otherwise, "msgs" should be a pointer to an "AV *" variable, in
which this function creates a new AV to contain any appropriate
messages. The elements of the array are ordered so that the first
message that would have been displayed is in the 0th element, and so
on. Each element is a hash with three key-value pairs, as follows:
"text"
The text of the message as a "SVpv".
"warn_categories"
The warning category (or categories) packed into a "SVuv".
"flag"
A single flag bit associated with this message, in a "SVuv".
The bit corresponds to some bit in the *errors return value,
such as "UTF8_GOT_LONG".
It's important to note that specifying this parameter as non-null
will cause any warnings this function would otherwise generate to be
suppressed, and instead be placed in *msgs. The caller can check
the lexical warnings state (or not) when choosing what to do with
the returned messages.
If the flag "UTF8_CHECK_ONLY" is passed, no warnings are generated,
and hence no AV is created.
The caller, of course, is responsible for freeing any returned AV.
UV utf8n_to_uvchr_msgs(const U8 *s, STRLEN curlen,
STRLEN *retlen, const U32 flags,
U32 *errors, AV **msgs)
"UTF8_SAFE_SKIP"
returns 0 if "s >= e"; otherwise returns the number of bytes in the
UTF-8 encoded character whose first byte is pointed to by "s". But
it never returns beyond "e". On DEBUGGING builds, it asserts that
"s <= e".
STRLEN UTF8_SAFE_SKIP(char* s, char* e)
"UTF8SKIP"
returns the number of bytes a non-malformed UTF-8 encoded character
whose first (perhaps only) byte is pointed to by "s".
If there is a possibility of malformed input, use instead:
"UTF8_SAFE_SKIP" if you know the maximum ending pointer in the
buffer pointed to by "s"; or
"UTF8_CHK_SKIP" if you don't know it.
It is better to restructure your code so the end pointer is passed
down so that you know what it actually is at the point of this call,
but if that isn't possible, "UTF8_CHK_SKIP" can minimize the chance
of accessing beyond the end of the input buffer.
STRLEN UTF8SKIP(char* s)
"UTF8_SKIP"
This is a synonym for "UTF8SKIP"
STRLEN UTF8_SKIP(char* s)
"utf8_to_bytes"
NOTE: "utf8_to_bytes" is experimental and may change or be removed
without notice.
Converts a string "s" of length *lenp from UTF-8 into native byte
encoding. Unlike "bytes_to_utf8", this over-writes the original
string, and updates *lenp to contain the new length. Returns zero
on failure (leaving "s" unchanged) setting *lenp to -1.
Upon successful return, the number of variants in the string can be
computed by having saved the value of *lenp before the call, and
subtracting the after-call value of *lenp from it.
If you need a copy of the string, see "bytes_from_utf8".
U8 * utf8_to_bytes(U8 *s, STRLEN *lenp)
"utf8_to_uvchr"
"DEPRECATED!" It is planned to remove "utf8_to_uvchr" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
Returns the native code point of the first character in the string
"s" which is assumed to be in UTF-8 encoding; "retlen" will be set
to the length, in bytes, of that character.
Some, but not all, UTF-8 malformations are detected, and in fact,
some malformed input could cause reading beyond the end of the input
buffer, which is why this function is deprecated. Use
"utf8_to_uvchr_buf" instead.
If "s" points to one of the detected malformations, and UTF8
warnings are enabled, zero is returned and *retlen is set (if
"retlen" isn't "NULL") to -1. If those warnings are off, the
computed value if well-defined (or the Unicode REPLACEMENT
CHARACTER, if not) is silently returned, and *retlen is set (if
"retlen" isn't NULL) so that ("s" + *retlen) is the next possible
position in "s" that could begin a non-malformed character. See
"utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is
returned.
UV utf8_to_uvchr(const U8 *s, STRLEN *retlen)
"utf8_to_uvchr_buf"
Returns the native code point of the first character in the string
"s" which is assumed to be in UTF-8 encoding; "send" points to 1
beyond the end of "s". *retlen will be set to the length, in bytes,
of that character.
If "s" does not point to a well-formed UTF-8 character and UTF8
warnings are enabled, zero is returned and *retlen is set (if
"retlen" isn't "NULL") to -1. If those warnings are off, the
computed value, if well-defined (or the Unicode REPLACEMENT
CHARACTER if not), is silently returned, and *retlen is set (if
"retlen" isn't "NULL") so that ("s" + *retlen) is the next possible
position in "s" that could begin a non-malformed character. See
"utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is
returned.
UV utf8_to_uvchr_buf(const U8 *s, const U8 *send, STRLEN *retlen)
"UVCHR_IS_INVARIANT"
Evaluates to 1 if the representation of code point "cp" is the same
whether or not it is encoded in UTF-8; otherwise evaluates to 0.
UTF-8 invariant characters can be copied as-is when converting
to/from UTF-8, saving time. "cp" is Unicode if above 255; otherwise
is platform-native.
bool UVCHR_IS_INVARIANT(UV cp)
"UVCHR_SKIP"
returns the number of bytes required to represent the code point
"cp" when encoded as UTF-8. "cp" is a native (ASCII or EBCDIC) code
point if less than 255; a Unicode code point otherwise.
STRLEN UVCHR_SKIP(UV cp)
"uvchr_to_utf8_flags"
Adds the UTF-8 representation of the native code point "uv" to the
end of the string "d"; "d" should have at least "UVCHR_SKIP(uv)+1"
(up to "UTF8_MAXBYTES+1") free bytes available. The return value is
the pointer to the byte after the end of the new character. In
other words,
d = uvchr_to_utf8_flags(d, uv, flags);
or, in most cases,
d = uvchr_to_utf8_flags(d, uv, 0);
This is the Unicode-aware way of saying
*(d++) = uv;
If "flags" is 0, this function accepts any code point from
0.."IV_MAX" as input. "IV_MAX" is typically 0x7FFF_FFFF in a 32-bit
word.
Specifying "flags" can further restrict what is allowed and not
warned on, as follows:
If "uv" is a Unicode surrogate code point and
"UNICODE_WARN_SURROGATE" is set, the function will raise a warning,
provided UTF8 warnings are enabled. If instead
"UNICODE_DISALLOW_SURROGATE" is set, the function will fail and
return NULL. If both flags are set, the function will both warn and
return NULL.
Similarly, the "UNICODE_WARN_NONCHAR" and "UNICODE_DISALLOW_NONCHAR"
flags affect how the function handles a Unicode non-character.
And likewise, the "UNICODE_WARN_SUPER" and "UNICODE_DISALLOW_SUPER"
flags affect the handling of code points that are above the Unicode
maximum of 0x10FFFF. Languages other than Perl may not be able to
accept files that contain these.
The flag "UNICODE_WARN_ILLEGAL_INTERCHANGE" selects all three of the
above WARN flags; and "UNICODE_DISALLOW_ILLEGAL_INTERCHANGE" selects
all three DISALLOW flags. "UNICODE_DISALLOW_ILLEGAL_INTERCHANGE"
restricts the allowed inputs to the strict UTF-8 traditionally
defined by Unicode. Similarly,
"UNICODE_WARN_ILLEGAL_C9_INTERCHANGE" and
"UNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE" are shortcuts to select
the above-Unicode and surrogate flags, but not the non-character
ones, as defined in Unicode Corrigendum #9
<https://www.unicode.org/versions/corrigendum9.html>. See
"Noncharacter code points" in perlunicode.
Extremely high code points were never specified in any standard, and
require an extension to UTF-8 to express, which Perl does. It is
likely that programs written in something other than Perl would not
be able to read files that contain these; nor would Perl understand
files written by something that uses a different extension. For
these reasons, there is a separate set of flags that can warn and/or
disallow these extremely high code points, even if other above-
Unicode ones are accepted. They are the
"UNICODE_WARN_PERL_EXTENDED" and "UNICODE_DISALLOW_PERL_EXTENDED"
flags. For more information see "UTF8_GOT_PERL_EXTENDED". Of
course "UNICODE_DISALLOW_SUPER" will treat all above-Unicode code
points, including these, as malformations. (Note that the Unicode
standard considers anything above 0x10FFFF to be illegal, but there
are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
A somewhat misleadingly named synonym for
"UNICODE_WARN_PERL_EXTENDED" is retained for backward compatibility:
"UNICODE_WARN_ABOVE_31_BIT". Similarly,
"UNICODE_DISALLOW_ABOVE_31_BIT" is usable instead of the more
accurately named "UNICODE_DISALLOW_PERL_EXTENDED". The names are
misleading because on EBCDIC platforms,these flags can apply to code
points that actually do fit in 31 bits. The new names accurately
describe the situation in all cases.
U8 * uvchr_to_utf8_flags(U8 *d, UV uv, UV flags)
"uvchr_to_utf8_flags_msgs"
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
Most code should use ""uvchr_to_utf8_flags"()" rather than call this
directly.
This function is for code that wants any warning and/or error
messages to be returned to the caller rather than be displayed. All
messages that would have been displayed if all lexical warnings are
enabled will be returned.
It is just like "uvchr_to_utf8_flags" but it takes an extra
parameter placed after all the others, "msgs". If this parameter is
0, this function behaves identically to "uvchr_to_utf8_flags".
Otherwise, "msgs" should be a pointer to an "HV *" variable, in
which this function creates a new HV to contain any appropriate
messages. The hash has three key-value pairs, as follows:
"text"
The text of the message as a "SVpv".
"warn_categories"
The warning category (or categories) packed into a "SVuv".
"flag"
A single flag bit associated with this message, in a "SVuv".
The bit corresponds to some bit in the *errors return value,
such as "UNICODE_GOT_SURROGATE".
It's important to note that specifying this parameter as non-null
will cause any warnings this function would otherwise generate to be
suppressed, and instead be placed in *msgs. The caller can check
the lexical warnings state (or not) when choosing what to do with
the returned messages.
The caller, of course, is responsible for freeing any returned HV.
U8 * uvchr_to_utf8_flags_msgs(U8 *d, UV uv, UV flags, HV **msgs)
"uvchr_to_utf8"
Adds the UTF-8 representation of the native code point "uv" to the
end of the string "d"; "d" should have at least "UVCHR_SKIP(uv)+1"
(up to "UTF8_MAXBYTES+1") free bytes available. The return value is
the pointer to the byte after the end of the new character. In
other words,
d = uvchr_to_utf8(d, uv);
is the recommended wide native character-aware way of saying
*(d++) = uv;
This function accepts any code point from 0.."IV_MAX" as input.
"IV_MAX" is typically 0x7FFF_FFFF in a 32-bit word.
It is possible to forbid or warn on non-Unicode code points, or
those that may be problematic by using "uvchr_to_utf8_flags".
U8 * uvchr_to_utf8(U8 *d, UV uv)
Utility Functions
"C_ARRAY_END"
Returns a pointer to one element past the final element of the input
C array.
void * C_ARRAY_END(void *a)
"C_ARRAY_LENGTH"
Returns the number of elements in the input C array (so you want
your zero-based indices to be less than but not equal to).
STRLEN C_ARRAY_LENGTH(void *a)
"getcwd_sv"
Fill "sv" with current working directory
int getcwd_sv(SV *sv)
"IN_PERL_COMPILETIME"
Returns 1 if this macro is being called during the compilation phase
of the program; otherwise 0;
bool IN_PERL_COMPILETIME
"IN_PERL_RUNTIME"
Returns 1 if this macro is being called during the execution phase
of the program; otherwise 0;
bool IN_PERL_RUNTIME
"IS_SAFE_SYSCALL"
Same as "is_safe_syscall".
bool IS_SAFE_SYSCALL(NN const char *pv, STRLEN len,
NN const char *what, NN const char *op_name)
"is_safe_syscall"
Test that the given "pv" (with length "len") doesn't contain any
internal "NUL" characters. If it does, set "errno" to "ENOENT",
optionally warn using the "syscalls" category, and return FALSE.
Return TRUE if the name is safe.
"what" and "op_name" are used in any warning.
Used by the IS_SAFE_SYSCALL() macro.
bool is_safe_syscall(const char *pv, STRLEN len,
const char *what, const char *op_name)
"my_setenv"
A wrapper for the C library setenv(3). Don't use the latter, as the
perl version has desirable safeguards
void my_setenv(const char *nam, const char *val)
"newPADxVOP"
Constructs, checks and returns an op containing a pad offset.
"type" is the opcode, which should be one of "OP_PADSV", "OP_PADAV",
"OP_PADHV" or "OP_PADCV". The returned op will have the "op_targ"
field set by the "padix" argument.
This is convenient when constructing a large optree in nested
function calls, as it avoids needing to store the pad op directly to
set the "op_targ" field as a side-effect. For example
o = op_append_elem(OP_LINESEQ, o,
newPADxVOP(OP_PADSV, 0, padix));
OP * newPADxVOP(I32 type, I32 flags, PADOFFSET padix)
"phase_name"
Returns the given phase's name as a NUL-terminated string.
For example, to print a stack trace that includes the current
interpreter phase you might do:
const char* phase_name = phase_name(PL_phase);
mess("This is weird. (Perl phase: %s)", phase_name);
const char * const phase_name(enum perl_phase)
"Poison"
PoisonWith(0xEF) for catching access to freed memory.
void Poison(void* dest, int nitems, type)
"PoisonFree"
PoisonWith(0xEF) for catching access to freed memory.
void PoisonFree(void* dest, int nitems, type)
"PoisonNew"
PoisonWith(0xAB) for catching access to allocated but uninitialized
memory.
void PoisonNew(void* dest, int nitems, type)
"PoisonWith"
Fill up memory with a byte pattern (a byte repeated over and over
again) that hopefully catches attempts to access uninitialized
memory.
void PoisonWith(void* dest, int nitems, type, U8 byte)
"StructCopy"
This is an architecture-independent macro that does a shallow copy
of one structure to another.
void StructCopy(type *src, type *dest, type)
"sv_destroyable"
Dummy routine which reports that object can be destroyed when there
is no sharing module present. It ignores its single SV argument,
and returns 'true'. Exists to avoid test for a "NULL" function
pointer and because it could potentially warn under some level of
strict-ness.
bool sv_destroyable(SV *sv)
"sv_nosharing"
Dummy routine which "shares" an SV when there is no sharing module
present. Or "locks" it. Or "unlocks" it. In other words, ignores
its single SV argument. Exists to avoid test for a "NULL" function
pointer and because it could potentially warn under some level of
strict-ness.
void sv_nosharing(SV *sv)
Versioning
"new_version"
Returns a new version object based on the passed in SV:
SV *sv = new_version(SV *ver);
Does not alter the passed in ver SV. See "upg_version" if you want
to upgrade the SV.
SV * new_version(SV *ver)
"PERL_REVISION"
"DEPRECATED!" It is planned to remove "PERL_REVISION" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
The major number component of the perl interpreter currently being
compiled or executing. This has been 5 from 1993 into 2020.
Instead use one of the version comparison macros. See
"PERL_VERSION_EQ".
"PERL_SUBVERSION"
"DEPRECATED!" It is planned to remove "PERL_SUBVERSION" from a
future release of Perl. Do not use it for new code; remove it from
existing code.
The micro number component of the perl interpreter currently being
compiled or executing. In stable releases this gives the dot
release number for maintenance updates. In development releases
this gives a tag for a snapshot of the status at various points in
the development cycle.
Instead use one of the version comparison macros. See
"PERL_VERSION_EQ".
"PERL_VERSION"
"DEPRECATED!" It is planned to remove "PERL_VERSION" from a future
release of Perl. Do not use it for new code; remove it from
existing code.
The minor number component of the perl interpreter currently being
compiled or executing. Between 1993 into 2020, this has ranged from
0 to 33.
Instead use one of the version comparison macros. See
"PERL_VERSION_EQ".
"PERL_VERSION_EQ"
"PERL_VERSION_GE"
"PERL_VERSION_GT"
"PERL_VERSION_LE"
"PERL_VERSION_LT"
"PERL_VERSION_NE"
Returns whether or not the perl currently being compiled has the
specified relationship to the perl given by the parameters. For
example,
#if PERL_VERSION_GT(5,24,2)
code that will only be compiled on perls after v5.24.2
#else
fallback code
#endif
Note that this is usable in making compile-time decisions
You may use the special value '*' for the final number to mean ALL
possible values for it. Thus,
#if PERL_VERSION_EQ(5,31,'*')
means all perls in the 5.31 series. And
#if PERL_VERSION_NE(5,24,'*')
means all perls EXCEPT 5.24 ones. And
#if PERL_VERSION_LE(5,9,'*')
is effectively
#if PERL_VERSION_LT(5,10,0)
This means you don't have to think so much when converting from the
existing deprecated "PERL_VERSION" to using this macro:
#if PERL_VERSION <= 9
becomes
#if PERL_VERSION_LE(5,9,'*')
bool PERL_VERSION_EQ(const U8 major, const U8 minor,
const U8 patch)
"prescan_version"
Validate that a given string can be parsed as a version object, but
doesn't actually perform the parsing. Can use either strict or lax
validation rules. Can optionally set a number of hint variables to
save the parsing code some time when tokenizing.
const char * prescan_version(const char *s, bool strict,
const char **errstr, bool *sqv,
int *ssaw_decimal, int *swidth,
bool *salpha)
"scan_version"
Returns a pointer to the next character after the parsed version
string, as well as upgrading the passed in SV to an RV.
Function must be called with an already existing SV like
sv = newSV(0);
s = scan_version(s, SV *sv, bool qv);
Performs some preprocessing to the string to ensure that it has the
correct characteristics of a version. Flags the object if it
contains an underscore (which denotes this is an alpha version).
The boolean qv denotes that the version should be interpreted as if
it had multiple decimals, even if it doesn't.
const char * scan_version(const char *s, SV *rv, bool qv)
"upg_version"
In-place upgrade of the supplied SV to a version object.
SV *sv = upg_version(SV *sv, bool qv);
Returns a pointer to the upgraded SV. Set the boolean qv if you
want to force this SV to be interpreted as an "extended" version.
SV * upg_version(SV *ver, bool qv)
"vcmp"
Version object aware cmp. Both operands must already have been
converted into version objects.
int vcmp(SV *lhv, SV *rhv)
"vnormal"
Accepts a version object and returns the normalized string
representation. Call like:
sv = vnormal(rv);
NOTE: you can pass either the object directly or the SV contained
within the RV.
The SV returned has a refcount of 1.
SV * vnormal(SV *vs)
"vnumify"
Accepts a version object and returns the normalized floating point
representation. Call like:
sv = vnumify(rv);
NOTE: you can pass either the object directly or the SV contained
within the RV.
The SV returned has a refcount of 1.
SV * vnumify(SV *vs)
"vstringify"
In order to maintain maximum compatibility with earlier versions of
Perl, this function will return either the floating point notation
or the multiple dotted notation, depending on whether the original
version contained 1 or more dots, respectively.
The SV returned has a refcount of 1.
SV * vstringify(SV *vs)
"vverify"
Validates that the SV contains valid internal structure for a
version object. It may be passed either the version object (RV) or
the hash itself (HV). If the structure is valid, it returns the HV.
If the structure is invalid, it returns NULL.
SV *hv = vverify(sv);
Note that it only confirms the bare minimum structure (so as not to
get confused by derived classes which may contain additional hash
entries):
• The SV is an HV or a reference to an HV
• The hash contains a "version" key
• The "version" key has a reference to an AV as its value
SV * vverify(SV *vs)
Warning and Dieing
In all these calls, the "U32 wn" parameters are warning category
constants. You can see the ones currently available in "Category
Hierarchy" in warnings, just capitalize all letters in the names and
prefix them by "WARN_". So, for example, the category "void" used in a
perl program becomes "WARN_VOID" when used in XS code and passed to one
of the calls below.
"ckWARN"
"ckWARN2"
"ckWARN3"
"ckWARN4"
These return a boolean as to whether or not warnings are enabled for
any of the warning category(ies) parameters: "w", "w1", ....
Should any of the categories by default be enabled even if not
within the scope of "use warnings", instead use the "ckWARN_d"
macros.
The categories must be completely independent, one may not be
subclassed from the other.
bool ckWARN (U32 w)
bool ckWARN2(U32 w1, U32 w2)
bool ckWARN3(U32 w1, U32 w2, U32 w3)
bool ckWARN4(U32 w1, U32 w2, U32 w3, U32 w4)
"ckWARN_d"
"ckWARN2_d"
"ckWARN3_d"
"ckWARN4_d"
Like "ckWARN", but for use if and only if the warning category(ies)
is by default enabled even if not within the scope of
"use warnings".
bool ckWARN_d (U32 w)
bool ckWARN2_d(U32 w1, U32 w2)
bool ckWARN3_d(U32 w1, U32 w2, U32 w3)
bool ckWARN4_d(U32 w1, U32 w2, U32 w3, U32 w4)
"ck_warner"
"ck_warner_d"
If none of the warning categories given by "err" are enabled, do
nothing; otherwise call "warner" or "warner_nocontext" with the
passed-in parameters;.
"err" must be one of the "packWARN", "packWARN2", "packWARN3",
"packWARN4" macros populated with the appropriate number of warning
categories.
The two forms differ only in that "ck_warner_d" should be used if
warnings for any of the categories are by default enabled.
NOTE: "ck_warner" must be explicitly called as "Perl_ck_warner" with
an "aTHX_" parameter.
NOTE: "ck_warner_d" must be explicitly called as "Perl_ck_warner_d"
with an "aTHX_" parameter.
void Perl_ck_warner(pTHX_ U32 err, const char *pat, ...)
"CLEAR_ERRSV"
Clear the contents of $@, setting it to the empty string.
This replaces any read-only SV with a fresh SV and removes any
magic.
void CLEAR_ERRSV()
"croak"
"croak_nocontext"
These are XS interfaces to Perl's "die" function.
They take a sprintf-style format pattern and argument list, which
are used to generate a string message. If the message does not end
with a newline, then it will be extended with some indication of the
current location in the code, as described for "mess_sv".
The error message will be used as an exception, by default returning
control to the nearest enclosing "eval", but subject to modification
by a $SIG{__DIE__} handler. In any case, these croak functions
never return normally.
For historical reasons, if "pat" is null then the contents of
"ERRSV" ($@) will be used as an error message or object instead of
building an error message from arguments. If you want to throw a
non-string object, or build an error message in an SV yourself, it
is preferable to use the "croak_sv" function, which does not involve
clobbering "ERRSV".
The two forms differ only in that "croak_nocontext" does not take a
thread context ("aTHX") parameter. It is usually preferred as it
takes up fewer bytes of code than plain "Perl_croak", and time is
rarely a critical resource when you are about to throw an exception.
NOTE: "croak" must be explicitly called as "Perl_croak" with an
"aTHX_" parameter.
void Perl_croak (pTHX_ const char *pat, ...)
void croak_nocontext(const char *pat, ...)
"croak_no_modify"
This encapsulates a common reason for dying, generating terser
object code than using the generic "Perl_croak". It is exactly
equivalent to "Perl_croak(aTHX_ "%s", PL_no_modify)" (which expands
to something like "Modification of a read-only value attempted").
Less code used on exception code paths reduces CPU cache pressure.
void croak_no_modify()
"croak_sv"
This is an XS interface to Perl's "die" function.
"baseex" is the error message or object. If it is a reference, it
will be used as-is. Otherwise it is used as a string, and if it
does not end with a newline then it will be extended with some
indication of the current location in the code, as described for
"mess_sv".
The error message or object will be used as an exception, by default
returning control to the nearest enclosing "eval", but subject to
modification by a $SIG{__DIE__} handler. In any case, the
"croak_sv" function never returns normally.
To die with a simple string message, the "croak" function may be
more convenient.
void croak_sv(SV *baseex)
"die"
"die_nocontext"
These behave the same as "croak", except for the return type. They
should be used only where the "OP *" return type is required. They
never actually return.
The two forms differ only in that "die_nocontext" does not take a
thread context ("aTHX") parameter, so is used in situations where
the caller doesn't already have the thread context.
NOTE: "die" must be explicitly called as "Perl_die" with an "aTHX_"
parameter.
OP * Perl_die (pTHX_ const char *pat, ...)
OP * die_nocontext(const char *pat, ...)
"die_sv"
This behaves the same as "croak_sv", except for the return type. It
should be used only where the "OP *" return type is required. The
function never actually returns.
OP * die_sv(SV *baseex)
"ERRSV"
Returns the SV for $@, creating it if needed.
SV * ERRSV
"fatal_warner"
Like "warner" except that it acts as if fatal warnings are enabled
for the warning.
If called when there are pending compilation errors this function
may return.
This is currently used to generate "used only once" fatal warnings
since the COP where the name being reported is no longer the current
COP when the warning is generated and may be useful for similar
cases.
"err" must be one of the "packWARN", "packWARN2", "packWARN3",
"packWARN4" macros populated with the appropriate number of warning
categories.
NOTE: "fatal_warner" must be explicitly called as
"Perl_fatal_warner" with an "aTHX_" parameter.
void Perl_fatal_warner(pTHX_ U32 err, const char *pat, ...)
"packWARN"
"packWARN2"
"packWARN3"
"packWARN4"
These macros are used to pack warning categories into a single U32
to pass to macros and functions that take a warning category
parameter. The number of categories to pack is given by the name,
with a corresponding number of category parameters passed.
U32 packWARN (U32 w1)
U32 packWARN2(U32 w1, U32 w2)
U32 packWARN3(U32 w1, U32 w2, U32 w3)
U32 packWARN4(U32 w1, U32 w2, U32 w3, U32 w4)
"SANE_ERRSV"
Clean up ERRSV so we can safely set it.
This replaces any read-only SV with a fresh writable copy and
removes any magic.
void SANE_ERRSV()
"vcroak"
This is an XS interface to Perl's "die" function.
"pat" and "args" are a sprintf-style format pattern and encapsulated
argument list. These are used to generate a string message. If the
message does not end with a newline, then it will be extended with
some indication of the current location in the code, as described
for "mess_sv".
The error message will be used as an exception, by default returning
control to the nearest enclosing "eval", but subject to modification
by a $SIG{__DIE__} handler. In any case, the "croak" function never
returns normally.
For historical reasons, if "pat" is null then the contents of
"ERRSV" ($@) will be used as an error message or object instead of
building an error message from arguments. If you want to throw a
non-string object, or build an error message in an SV yourself, it
is preferable to use the "croak_sv" function, which does not involve
clobbering "ERRSV".
void vcroak(const char *pat, va_list *args)
"vfatal_warner"
This is like "fatal_warner" but "args" are an encapsulated argument
list.
void vfatal_warner(U32 err, const char *pat, va_list *args)
"vwarn"
This is an XS interface to Perl's "warn" function.
This is like "warn", but "args" are an encapsulated argument list.
Unlike with "vcroak", "pat" is not permitted to be null.
void vwarn(const char *pat, va_list *args)
"vwarner"
This is like "warner", but "args" are an encapsulated argument list.
void vwarner(U32 err, const char *pat, va_list *args)
"warn"
"warn_nocontext"
These are XS interfaces to Perl's "warn" function.
They take a sprintf-style format pattern and argument list, which
are used to generate a string message. If the message does not end
with a newline, then it will be extended with some indication of the
current location in the code, as described for "mess_sv".
The error message or object will by default be written to standard
error, but this is subject to modification by a $SIG{__WARN__}
handler.
Unlike with "croak", "pat" is not permitted to be null.
The two forms differ only in that "warn_nocontext" does not take a
thread context ("aTHX") parameter, so is used in situations where
the caller doesn't already have the thread context.
NOTE: "warn" must be explicitly called as "Perl_warn" with an
"aTHX_" parameter.
void Perl_warn (pTHX_ const char *pat, ...)
void warn_nocontext(const char *pat, ...)
"warner"
"warner_nocontext"
These output a warning of the specified category (or categories)
given by "err", using the sprintf-style format pattern "pat", and
argument list.
"err" must be one of the "packWARN", "packWARN2", "packWARN3",
"packWARN4" macros populated with the appropriate number of warning
categories. If any of the warning categories they specify is fatal,
a fatal exception is thrown.
In any event a message is generated by the pattern and arguments.
If the message does not end with a newline, then it will be extended
with some indication of the current location in the code, as
described for "mess_sv".
The error message or object will by default be written to standard
error, but this is subject to modification by a $SIG{__WARN__}
handler.
"pat" is not permitted to be null.
The two forms differ only in that "warner_nocontext" does not take a
thread context ("aTHX") parameter, so is used in situations where
the caller doesn't already have the thread context.
These functions differ from the similarly named "warn" functions, in
that the latter are for XS code to unconditionally display a
warning, whereas these are for code that may be compiling a perl
program, and does extra checking to see if the warning should be
fatal.
NOTE: "warner" must be explicitly called as "Perl_warner" with an
"aTHX_" parameter.
void Perl_warner (pTHX_ U32 err, const char *pat, ...)
void warner_nocontext(U32 err, const char *pat, ...)
"warn_sv"
This is an XS interface to Perl's "warn" function.
"baseex" is the error message or object. If it is a reference, it
will be used as-is. Otherwise it is used as a string, and if it
does not end with a newline then it will be extended with some
indication of the current location in the code, as described for
"mess_sv".
The error message or object will by default be written to standard
error, but this is subject to modification by a $SIG{__WARN__}
handler.
To warn with a simple string message, the "warn" function may be
more convenient.
void warn_sv(SV *baseex)
XS
xsubpp compiles XS code into C. See "xsubpp" in perlutil.
"aMY_CXT"
Described in perlxs.
"_aMY_CXT"
Described in perlxs.
"aMY_CXT_"
Described in perlxs.
"ax"
Variable which is setup by "xsubpp" to indicate the stack base
offset, used by the "ST", "XSprePUSH" and "XSRETURN" macros. The
"dMARK" macro must be called prior to setup the "MARK" variable.
Stack_off_t ax
"CLASS"
Variable which is setup by "xsubpp" to indicate the class name for a
C++ XS constructor. This is always a "char*". See "THIS".
char* CLASS
"dAX"
Sets up the "ax" variable. This is usually handled automatically by
"xsubpp" by calling "dXSARGS".
dAX;
"dAXMARK"
Sets up the "ax" variable and stack marker variable "mark". This is
usually handled automatically by "xsubpp" by calling "dXSARGS".
dAXMARK;
"dITEMS"
Sets up the "items" variable. This is usually handled automatically
by "xsubpp" by calling "dXSARGS".
dITEMS;
"dMY_CXT"
Described in perlxs.
"dMY_CXT_SV"
Now a placeholder that declares nothing
dMY_CXT_SV;
"dUNDERBAR"
Sets up any variable needed by the "UNDERBAR" macro. It used to
define "padoff_du", but it is currently a noop. However, it is
strongly advised to still use it for ensuring past and future
compatibility.
dUNDERBAR;
"dXSARGS"
Sets up stack and mark pointers for an XSUB, calling "dSP" and
"dMARK". Sets up the "ax" and "items" variables by calling "dAX"
and "dITEMS". This is usually handled automatically by "xsubpp".
dXSARGS;
"dXSI32"
Sets up the "ix" variable for an XSUB which has aliases. This is
usually handled automatically by "xsubpp".
dXSI32;
"items"
Variable which is setup by "xsubpp" to indicate the number of items
on the stack. See "Variable-length Parameter Lists" in perlxs.
Stack_off_t items
"ix"
Variable which is setup by "xsubpp" to indicate which of an XSUB's
aliases was used to invoke it. See "The ALIAS: Keyword" in perlxs.
I32 ix
"MY_CXT"
Described in perlxs.
"MY_CXT_CLONE"
Described in perlxs.
"MY_CXT_INIT"
Described in perlxs.
"pMY_CXT"
Described in perlxs.
"_pMY_CXT"
Described in perlxs.
"pMY_CXT_"
Described in perlxs.
"RETVAL"
Variable which is setup by "xsubpp" to hold the return value for an
XSUB. This is always the proper type for the XSUB. See "The RETVAL
Variable" in perlxs.
type RETVAL
"ST"
Used to access elements on the XSUB's stack.
SV* ST(int ix)
"START_MY_CXT"
Described in perlxs.
"THIS"
Variable which is setup by "xsubpp" to designate the object in a C++
XSUB. This is always the proper type for the C++ object. See
"CLASS" and "Using XS With C++" in perlxs.
type THIS
"UNDERBAR"
The SV* corresponding to the $_ variable. Works even if there is a
lexical $_ in scope.
"XS"
Macro to declare an XSUB and its C parameter list. This is handled
by "xsubpp". It is the same as using the more explicit
"XS_EXTERNAL" macro; the latter is preferred.
"XS_EXTERNAL"
Macro to declare an XSUB and its C parameter list explicitly
exporting the symbols.
"XS_INTERNAL"
Macro to declare an XSUB and its C parameter list without exporting
the symbols. This is handled by "xsubpp" and generally preferable
over exporting the XSUB symbols unnecessarily.
"XSPROTO"
Macro used by "XS_INTERNAL" and "XS_EXTERNAL" to declare a function
prototype. You probably shouldn't be using this directly yourself.
Undocumented elements
The following functions have been flagged as part of the public API, but
are currently undocumented. Use them at your own risk, as the
interfaces are subject to change. Functions that are not listed in this
document are not intended for public use, and should NOT be used under
any circumstances.
If you feel you need to use one of these functions, first send email to
perl5-porters@perl.org <mailto:perl5-porters@perl.org>. It may be that
there is a good reason for the function not being documented, and it
should be removed from this list; or it may just be that no one has
gotten around to documenting it. In the latter case, you will be asked
to submit a patch to document the function. Once your patch is
accepted, it will indicate that the interface is stable (unless it is
explicitly marked otherwise) and usable by you.
clone_params_del do_open PERL_BUILD_DATE sv_dup
clone_params_new do_openn resume_compcv sv_dup_inc
Next are the API-flagged elements that are considered experimental.
Using one of these is even more risky than plain undocumented ones.
They are listed here because they should be listed somewhere (so their
existence doesn't get lost) and this is the best place for them.
apply_attrs_string hv_store_flags thread_locale_init
gv_fetchmethod_pv_flags leave_adjust_stacks thread_locale_term
gv_fetchmethod_pvn_flags newXS_flags
gv_fetchmethod_sv_flags savetmps
Finally are deprecated undocumented API elements. Do not use any for
new code; remove all occurrences of all of these from existing code.
There are currently no items of this type
AUTHORS
Until May 1997, this document was maintained by Jeff Okamoto
<okamoto@corp.hp.com>. It is now maintained as part of Perl itself.
With lots of help and suggestions from Dean Roehrich, Malcolm Beattie,
Andreas Koenig, Paul Hudson, Ilya Zakharevich, Paul Marquess, Neil
Bowers, Matthew Green, Tim Bunce, Spider Boardman, Ulrich Pfeifer,
Stephen McCamant, and Gurusamy Sarathy.
API Listing originally by Dean Roehrich <roehrich@cray.com>.
Updated to be autogenerated from comments in the source by Benjamin
Stuhl.
SEE ALSO
config.h, perlapio, perlcall, perlclib, perlembed, perlfilter, perlguts,
perlhacktips, perlintern, perlinterp, perliol, perlmroapi, perlreapi,
perlreguts, perlxs
perl v5.40.1 2026-08-30 PERLAPI(1)
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