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 described 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 processing.

       Multiple flags may be specified by binary or:ing  them  together,  for  example  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

REPORTING BUGS

       Report bugs to <help-libidn@gnu.org>.
       General guidelines for reporting bugs: https://www.gnu.org/gethelp/
       Libidn2 home page: https://www.gnu.org/software/libidn2/

COPYRIGHT

       Copyright © 2002-2025 Simon Josefsson.
       Copying  and distribution of this file, with or without modification, are permitted in any medium without
       royalty provided the copyright notice and this notice are preserved.

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                                               2.3.8                                    idn2_lookup_ul(3)