bindtextdomain specifies that the domainname message catalog will be found in the dirname directory hierarchy, rather than in the system locale data base.
bindtextdomain applies domainname to the currently active LC_MESSAGE locale. This usage is equivalent in syntax and meaning to the textdomain function's application of domainname, except that the selection of the domain in bind_textdomain_codeset is valid only for the duration of the call.
dirname can be an absolute or relative pathname.
On success, bindtextdomain returns the directory pathname currently bound to the domain. On failure, a NULL pointer is returned.
gettext, dgettext, ngettext, dngettext, dcgettext, dcngettext, textdomain, bindtextdomain, bind_textdomain_codeset