XtAppErrorMsg(3)

💖 XtAppErrorMsg(3) — the XT FUNCTIONS girlies 💖

okay bestie, sit down, hydrate, because today we're talking about high-level error handlers from libXt. yes THAT libXt. the one that's been holding X Toolkit apps together since before either of us was born. she's iconic, she's dramatic, and she does NOT return (more on that in a sec 🫣).

This whole page lives in the XT FUNCTIONS section of the manual, and it's covering four little besties: XtAppErrorMsg, XtAppSetErrorMsgHandler, XtAppSetWarningMsgHandler, and XtAppWarningMsg.

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✨ NAME ✨

XtAppErrorMsg, XtAppSetErrorMsgHandler, XtAppSetWarningMsgHandler, XtAppWarningMsg — high-level error handlers, no cap 💅

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🌸 SYNTAX 🌸

#include <X11/Intrinsic.h>

_X_NORETURN void XtAppErrorMsg(XtAppContext app_context, const char
       *name, const char *type, const char *class, const char
       *defaultMsg, String *params, Cardinal *num_params);

XtErrorMsgHandler XtAppSetErrorMsgHandler(XtAppContext app_context,
       _X_NORETURN XtErrorMsgHandler msg_handler);

XtErrorMsgHandler XtAppSetWarningMsgHandler(XtAppContext app_context,
       XtErrorMsgHandler msg_handler);

void XtAppWarningMsg(XtAppContext app_context, const char *name, const
       char *type, const char *class, const char *defaultMsg, String
       *params, Cardinal *num_params);

notice the _X_NORETURN on two of them?? that's not a vibe, that's a warning. those functions literally do not come back. they're the friend who says "brb" and moves to another country. 😭

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🎀 ARGUMENTS 🎀

• app_context — specifies the application context. every one of these girlies needs to know which app she's working with. it's giving "who's your manager".
• class — specifies the resource class of the error message. the category, the genre, the aesthetic of the error.
• defaultMsg — specifies the default message to use. the fallback text, the backup outfit if the main one doesn't hit.
• name — specifies the general kind of error. the broad vibe. the "family" of the error.
• type — specifies the detailed name of the error. the specific vibe. the exact flavour.
• msg_handler — specifies the new fatal error procedure, which should not return or the nonfatal error procedure, which usually returns. yes queen, read that again: the fatal one should not return, the nonfatal one usually returns. know the difference, it's lowkey important 🫶
• num_params — specifies the number of values in the parameter list. count them, bestie.
• params — specifies a pointer to a list of values to be stored in the message. it's a pointer, it points, that's the whole job.

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💜 DESCRIPTION 💜

So here's the tea, fr fr:

The XtAppErrorMsg function calls the high-level error handler and passes the specified information. that's it, that's the move — it's the messenger girlie. she doesn't fix anything, she just delivers the info and lets the handler do her thing. 💅

The XtAppSetErrorMsgHandler function registers the specified procedure, which is called when a fatal error occurs. so like, you're picking who's on duty when everything is on fire. choose wisely. 🔥

The XtAppSetWarningMsgHandler function registers the specified procedure, which is called when a nonfatal error condition occurs. the "hey girl just so you know" department. still important, just less screaming. 🌸

The XtAppWarningMsg function calls the high-level error handler and passes the specified information. same energy as XtAppErrorMsg, different severity. one is a fire alarm, one is a tap on the shoulder.

⚠️ friendly reminder from your girl: XtAppErrorMsg is _X_NORETURN, meaning it does not return. don't be out here writing code after it like it's coming back. it is not. periodt.

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🦋 SEE ALSO 🦋

• XtAppGetErrorDatabase(3)
• XtAppError(3)
• X Toolkit Intrinsics - C Language Interface
• Xlib - C Language X Interface

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👑 sign-off 👑

this page comes to you courtesy of X Version 11, libXt 1.3.1, and it's filed under XtAppErrorMsg(3) in the manual. read her, love her, handle your errors responsibly. mwah 💋✨🌈