XtAppInitialize(3)

✨ XtAppInitialize — the X Toolkit Intrinsics era ✨

bestie we are SO back in the XT FUNCTIONS section of the manual, and today's main character is XtAppInitialize (and its glamorous understudy XtVaAppInitialize). They initialize, open, or close a display. That's the whole vibe. Let's get into it 💅

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🌸 NAME 🌸

XtAppInitialize, XtVaAppInitialize — initialize, open, or close a display 🦋

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🎀 SYNTAX 🎀

okay so first you gotta invite the header in:

#include <X11/Intrinsic.h>

Widget XtAppInitialize(XtAppContext* app_context_return, const char
       *application_class, XrmOptionDescRec* options, Cardinal
       num_options, int *argc_in_out, char **argv_in_out, String
       *fallback_resources, ArgList args, Cardinal num_args);

Widget XtVaAppInitialize(XtAppContext* app_context_return, const char
       *application_class, XrmOptionDescRec* options, Cardinal
       num_options, int *argc_in_out, char **argv_in_out, String
       *fallback_resources, ...);

like yes, that's a LOT of arguments. she's high maintenance and she's worth it 🫶

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💖 ARGUMENTS 💖

• app_context_return — Specifies the application context. that's it, that's the assignment ✨
• application_class — Specifies the class name of this application, which usually is the generic name for all instances of this application. (iykyk — think of it as the family name, not the government name 👑)
• options — Specifies how to parse the command line for any application-specific resources. The options argument is passed as a parameter to XrmParseCommand. For further information, see Xlib - C Language X Interface. she's giving middle-management energy, but make it X11 🧚
• num_options — Specifies the number of entries in the options list. (yes bestie, you have to count them yourself 😭)
• argc_in_out — Specifies a pointer to the number of command line parameters.
• argv_in_out — Specifies the command line parameters.
• fallback_resources — Specifies resource values to be used if the application class resource file cannot be opened or read, or NULL. your backup plan, but make it resources 🌈
• args — Specifies the argument list to override any other resource specification for the created shell widget. she said "my rules now" 💅
• num_args — Specifies the number of entries in the argument list.
• ... — Specifies the variable argument list to override any other resource specification for the created shell widget. (the XtVa flavor's little ✨mystery✨)

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🔥 DESCRIPTION 🔥

okay so here's the tea. The XtAppInitialize function calls XtToolkitInitialize followed by XtCreateApplicationContext, then calls XtOpenDisplay with display_string NULL and application_name NULL, and finally calls XtAppCreateShell with application_name NULL, widget_class applicationShellWidgetClass, and the specified args and num_args and returns the created shell. she's doing the whole morning routine in one function call, periodt 💖

The modified argc and argv returned by XtDisplayInitialize are returned in argc_in_out and argv_in_out. If app_context_return is not NULL, the created application context is also returned. If the display specified by the command line cannot be opened, an error message is issued and XtAppInitialize terminates the application. If fallback_resources is non-NULL, XtAppSetFallbackResources is called with the value prior to calling XtOpenDisplay.

⚠️ bestie listen. if the display can't be opened, she doesn't warn you and keep going — she terminates the application. no cap. so make sure your display situation is sorted before you call her 🙈

and now for the part where the elders get gently retired:

XtAppInitialize and XtVaAppInitialize have been superseded by XtOpenApplication and XtVaOpenApplication respectively.

not me calling them old 💀 — they still work, they're just the legacy icons of the family, and we respect our elders even while we're using the new ones ✨

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🌟 SEE ALSO 🌟

• XtOpenApplication(3), XtVaOpenApplication(3)
• X Toolkit Intrinsics - C Language Interface
• Xlib - C Language X Interface

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okay that's the whole page bestie, you ate that 💅✨

this masterpiece comes to you from X Version 11, libXt 1.3.1, filed under XtAppInitialize(3). go forth and initialize your display, queen 👑💖