Title: Internationalization

# Internationalization

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, you must include `<glib/gi18n-lib.h>`
after defining the `GETTEXT_PACKAGE` macro suitably for your library:

```c
#define GETTEXT_PACKAGE "gtk4"
#include <glib/gi18n-lib.h>
```

For an application, note that you also have to call `bindtextdomain()`,
`bind_textdomain_codeset()`, `textdomain()` and `setlocale()` early on in your
`main()` to make `gettext()` work. For example:

```c
#include <glib/gi18n.h>
#include <locale.h>

int
main (int argc, char **argv)
{
  setlocale (LC_ALL, "");
  bindtextdomain (GETTEXT_PACKAGE, DATADIR "/locale");
  bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
  textdomain (GETTEXT_PACKAGE);

  // Rest of your application.
}
```

where `DATADIR` is as typically provided by Automake or Meson.

For a library, you only have to call `bindtextdomain()` and
`bind_textdomain_codeset()` in your initialization function. If your library
doesn't have an initialization function, you can call the functions before
the first translated message.

The [gettext
manual](http://www.gnu.org/software/gettext/manual/gettext.html#Maintainers)
covers details of how to integrate gettext into a project’s build system and
workflow.