Description GLib doesn't force any particular localization method upon its users. But since GLib itself is localized using the gettext() mechanism, it seems natural to offer the de-facto standard gettext() support macros in an easy-to-use form. In order to use these macros in an application, you must include glib/gi18n.h. For use in a library, must include glib/gi18n-lib.h after defining the GETTEXT_PACKAGE macro suitably for your library: Note that you also have to call setlocale() and textdomain() (as well as bindtextdomain() and bind_textdomain_codeset()) early on in your main() to make gettext() work. The gettext manual covers details of how to set up message extraction with xgettext.