XtSetLanguageProc(3)

💖 XtSetLanguageProc — setting the language procedure, bestie 💖

okay so this is one of those XT FUNCTIONS pages from XtSetLanguageProc(3) and honestly? it's lowkey iconic. it's the lil' function that decides how your app figures out what language and locale it should be speaking. let's get into it 🫶

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✨ NAME ✨

XtSetLanguageProc — set the language procedure. that's it, that's the whole job, and she does it flawlessly 💅

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🌸 SYNTAX 🌸

#include <X11/Intrinsic.h>

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

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🎀 ARGUMENTS 🎀

• app_context — the application context where this language procedure is gonna live, or NULL. yes, NULL is a valid choice here, she's flexible like that ✨
• proc — the language procedure itself, or NULL. (NULL means "gimme the default one," keep reading bestie 👀)
• client_data — extra client data that gets passed along to the language procedure whenever it gets called. lil' care package for your callback 🎁

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🦋 DESCRIPTION 🦋

so here's the tea. XtSetLanguageProc sets the language procedure that will be called from XtDisplayInitialize for all subsequent Displays initialized in the specified application context. every. single. one. periodt.

if app_context is NULL, the language procedure you specified gets registered in all application contexts created by the calling process, including any future application contexts that may be created. yes, even the ones that don't exist yet. she's thinking ahead, main character energy fr fr 👑

if proc is NULL, a default language procedure is registered instead.

and the best part? XtSetLanguageProc returns the previously registered language procedure. 🎉

heads up though — if a language procedure has not yet been registered, the return value is unspecified. but if you take that return value and use it in a subsequent call to XtSetLanguageProc, it will cause the default language procedure to be registered. so like, it's not useless, it's just mysterious. iykyk 💀

🌈 what the default language procedure actually does 🌈

okay so the default one is out here doing the absolute most, and honestly? we love her for it:

• 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". no cap, it just gives up and goes with "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 ).

💜 how to actually use this 💜

a client wishing to use this mechanism to establish locale can do so by calling XtSetLanguageProc prior to XtDisplayInitialize. that's the move. do it before, not after, or it's giving... nothing. 🙈

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⭐ SEE ALSO ⭐

• X Toolkit Intrinsics - C Language Interface
• Xlib - C Language X Interface

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and that's the whole page bestie!! 🎀 this one came from X Version 11, libXt 1.3.1, and honestly she ate and left no crumbs. go set some locales, you've got this 💖✨🦋