XtSetLanguageProc(3) set the language procedure


Widget XtSetLanguageProc(XtAppContext app_context, XtLanguageProc proc, XtPointer client_data);


Specifies the application context in which the language procedure is to be used, or NULL.

Specifies the language procedure, or NULL.

Specifies additional client data to be passed to the language procedure when it is called.


XtSetLanguageProc sets the language procedure that will be called from XtDisplayInitialize for all subsequent Displays initialized in the specified application context. If app_context is NULL, the specified language procedure is registered in all application contexts created by the calling process, including any future application contexts that may be created. If proc is NULL a default language procedure is registered. XtSetLanguageProc returns the previously registered language procedure. If a language procedure has not yet been registered, the return value is unspecified but if this return value is used in a subsequent call to XtSetLanguageProc, it will cause the default language procedure to be registered.

The default language procedure does the following:

  • Sets the locale according to the environment. On ANSI C-based systems this is done by calling setlocale( LC_ALL, language ). If an error is encountered a warning message is issued with XtWarning.
  • Calls XSupportsLocale to verify that the current locale is supported. If the locale is not supported, a warning message is issued with XtWarning and the locale is set to ``C''.
  • Calls XSetLocaleModifiers specifying the empty string.
  • Returns the value of the current locale. On ANSI C-based systems this is the return value from a final call to setlocale( LC_ALL, NULL ).

A client wishing to use this mechanism to establish locale can do so by calling XtSetLanguageProc prior to XtDisplayInitialize.