XkbListComponents(3) XKB FUNCTIONS XkbListComponents(3)
NAME
XkbListComponents - List of components for one or more component types
SYNOPSIS
XkbComponentListPtr XkbListComponents (Display *dpy, unsigned int de-
vice_spec, XkbComponentNamesPtr ptrns, int *max_inout);
ARGUMENTS
dpy connection to X server
device_spec
device ID, or XkbUseCoreKbd
ptrns namelist for components of interest
max_inout
max # returned names, # left over
DESCRIPTION
You may ask the server for a list of components for one or more compo-
nent types. The request takes the form of a set of patterns, one pattern
for each of the component types, including a pattern for the complete
keyboard description. To obtain this list, use XkbListComponents.
XkbListComponents queries the server for a list of component names
matching the patterns specified in ptrns. It waits for a reply and re-
turns the matching component names in an XkbComponentListRec structure.
When you are done using the structure, you should free it using
XkbFreeComponentList. device_spec indicates a particular device in which
the caller is interested. A server is allowed (but not required) to re-
strict its reply to portions of the database that are relevant for that
particular device.
ptrns is a pointer to an XkbComponentNamesRec. Each of the fields in
ptrns contains a pattern naming the components of interest. Each of the
patterns is composed of characters from the ISO Latin1 encoding, but can
contain only parentheses, the wildcard characters `?' and `*', and char-
acters permitted in a component class or member name. A pattern may be
NULL, in which case no components for that type is returned. Pattern
matches with component names are case sensitive. The `?' wildcard
matches any single character, except a left or right parenthesis; the
`*' wildcard matches any number of characters, except a left or right
parenthesis. If an implementation allows additional characters in a com-
ponent class or member name other than those required by the Xkb exten-
sion, the result of comparing one of the additional characters to either
of the wildcard characters is implementation-dependent.
If a pattern contains illegal characters, the illegal characters are ig-
nored. The matching process is carried out as if the illegal characters
were omitted from the pattern.
max_inout is used to throttle the amount of data passed to and from the
server. On input, it specifies the maximum number of names to be re-
turned (the total number of names in all component categories). Upon re-
turn from XkbListComponents, max_inout contains the number of names that
matched the request but were not returned because of the limit.
Component Names
Component names have the form class(member) where class describes a sub-
set of the available components for a particular type and the optional
member identifies a specific component from that subset. For example,
the name "atlantis(acme)" for a symbols component might specify the sym-
bols used for the atlantis national keyboard layout by the vendor
"acme." Each class has an optional default member - references that
specify a class but not a member refer to the default member of the
class, if one exists. Xkb places no constraints on the interpretation of
the class and member names used in component names.
The class and member names are both specified using characters from the
Latin-1 character set. Xkb implementations must accept all alphanumeric
characters, minus (`-') and underscore (`_') in class or member names,
and must not accept parentheses, plus, vertical bar, percent sign, as-
terisk, question mark, or white space. The use of other characters is
implementation-dependent.
STRUCTURES
The component name patterns used to describe the request are passed to
XkbListComponents using an XkbComponentNamesRec structure. This struc-
ture has no special allocation constraints or interrelationships with
other structures; allocate and free this structure using standard malloc
and free calls or their equivalent:
typedef struct _XkbComponentNames {
char * keymap; /* keymap names */
char * keycodes; /* keycode names */
char * types; /* type names */
char * compat; /* compatibility map names */
char * symbols; /* symbol names */
char * geometry; /* geometry names */
} XkbComponentNamesRec, *XkbComponentNamesPtr;
XkbListComponents returns a pointer to an XkbComponentListRec:
typedef struct _XkbComponentList {
int num_keymaps; /* number of entries in keymap */
int num_keycodes; /* number of entries in keycodes */
int num_types; /* number of entries in types */
int num_compat; /* number of entries in compat */
int num_symbols; /* number of entries in symbols */
int num_geometry; /* number of entries in geometry;
XkbComponentNamePtr keymap; /* keymap names */
XkbComponentNamePtr keycodes; /* keycode names */
XkbComponentNamePtr types; /* type names */
XkbComponentNamePtr compat; /* compatibility map names */
XkbComponentNamePtr symbols; /* symbol names */
XkbComponentNamePtr geometry; /* geometry names */
} XkbComponentListRec, *XkbComponentListPtr;
typedef struct _XkbComponentName {
unsigned short flags; /* hints regarding component name */
char * name; /* name of component */
} XkbComponentNameRec, *XkbComponentNamePtr;
SEE ALSO
XkbFreeComponentList(3)
NOTES
Note that the structure used to specify patterns on input is an XkbCom-
ponentNamesRec, and that used to hold the individual component names
upon return is an XkbComponentNameRec (no trailing `s' in Name).
X Version 11 libX11 1.8.12 XkbListComponents(3)
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