textdomain - set domain for future gettext() calls
#include <libintl.h>
char * textdomain (const char * domainname);The textdomain function sets or retrieves the current message domain.
A message domain is a set of translatable msgid messages. Usually, every software package has its own message domain. The domain name is used to determine the message catalog where a translation is looked up; it must be a non-empty string.
The current message domain is used by the gettext, ngettext functions, and by the dgettext, dcgettext, dngettext and dcngettext functions when called with a NULL domainname argument.
If domainname is not NULL, the current message domain is set to domainname. The string the function stores internally is a copy of the domainname argument.
If domainname is NULL, the function returns the current message domain.
If successful, the textdomain function returns the current message domain, after possibly changing it. The resulting string is valid until the next textdomain call and must not be modified or freed. If a memory allocation failure occurs, it sets errno to ENOMEM and returns NULL.
The following error can occur, among others:
Not enough memory available.
The return type ought to be const char *, but is char * to avoid warnings in C code predating ANSI C.
gettext(3), ngettext(3), bindtextdomain(3), bind_textdomain_codeset(3)