idn2_lookup_ul(3) libidn2 idn2_lookup_ul(3)
NAME
idn2_lookup_ul - API function
SYNOPSIS
#include <idn2.h>
int idn2_lookup_ul(const char * src, char ** lookupname, int flags);
ARGUMENTS
const char * src
input zero-terminated locale encoded string.
char ** lookupname
newly allocated output variable with name to lookup in DNS.
int flags optional idn2_flags to modify behaviour.
DESCRIPTION
Perform IDNA2008 lookup string conversion on domain name src , as de-
scribed in section 5 of RFC 5891. Note that the input is assumed to be
encoded in the locale's default coding system, and will be transcoded
to UTF-8 and NFC normalized by this function.
Pass IDN2_ALABEL_ROUNDTRIP in flags to convert any input A-labels to
U-labels and perform additional testing. This is default since version
2.2. To switch this behavior off, pass IDN2_NO_ALABEL_ROUNDTRIP
Pass IDN2_TRANSITIONAL to enable Unicode TR46 transitional processing,
and IDN2_NONTRANSITIONAL to enable Unicode TR46 non-transitional pro-
cessing.
Multiple flags may be specified by binary or:ing them together, for ex-
ample IDN2_ALABEL_ROUNDTRIP | IDN2_NONTRANSITIONAL.
The IDN2_NFC_INPUT in flags is always enabled in this function.
After version 0.11: lookupname may be NULL to test lookup of src
without allocating memory.
RETURNS
On successful conversion IDN2_OK is returned, if conversion from locale
to UTF-8 fails then IDN2_ICONV_FAIL is returned, if the output domain
or any label would have been too long IDN2_TOO_BIG_DOMAIN or
IDN2_TOO_BIG_LABEL is returned, or another error code is returned.
SINCE
0.1
SEE ALSO
The full documentation for libidn2 is maintained as a Texinfo manual.
If the info and libidn2 programs are properly installed at your site,
the command
info libidn2
should give you access to the complete manual. As an alternative you
may obtain the manual from:
https://www.gnu.org/software/libidn/libidn2/manual/
libidn2 2.3.1.48-1925 idn2_lookup_ul(3)
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