The bindtextdomain function sets the base directory of the hierarchy
containing message catalogs for a given message domain.
A message domain is a set of translatable msgid messages. Usually,
every software package has its own message domain. The need for calling
bindtextdomain arises because packages are not always installed with
the same prefix as the <libintl.h> header and the libc/libintl libraries.
Message catalogs will be expected at the pathnames
where locale is a locale name and category is a locale facet such
domainname must be a non-empty string.
If dirname is not NULL, the base directory for message catalogs belonging
to domain domainname is set to dirname. The function makes copies
of the argument strings as needed. If the program wishes to call the
chdir function, it is important that dirname be an absolute
pathname; otherwise it cannot be guaranteed that the message catalogs will
If dirname is NULL, the function returns the previously set base
directory for domain domainname.