XErrorEvent(3)

💅 XErrorEvent(3) — like, the X error event struct, bestie

okay so this one lives in the XLIB FUNCTIONS family, and honestly? it's the ✨receipt✨ you get when X is like "girl, that request did NOT go through." 🫶

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✨ NAME ✨

XErrorEvent — the X error event structure. yep, that's the whole vibe. it's a struct. it holds the tea about what went wrong. 🍓

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🎀 STRUCTURES 🎀

bestie. sit down. here's the whole thing, and i mean the whole thing, comments and all, no cap:

typedef struct {
        int type;
        Display *display;       /* Display the event was read from */
        XID resourceid;         /* resource id */
        unsigned long serial;           /* serial number of failed request */
        unsigned char error_code;       /* error code of failed request */
        unsigned char request_code;     /* Major op-code of failed request */
        unsigned char minor_code;       /* Minor op-code of failed request */
} XErrorEvent;

like, that's it. that's the icon. 👑

when you receive this event, the structure members are set as follows — main character energy, every field doing its job:

• type — it's there, it's the type field, we love her.
• display — the display the event was read from.
• resourceid — the resource id, i.e. which thing was involved.
• serial — the serial number of the failed request. more on her in a sec 👇
• error_code — the error code of the failed request. this is the actual "what went wrong."
• request_code — the major op-code of the failed request.
• minor_code — the minor op-code of the failed request.

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🦋 the serial member, explained 🦋

okay so serial is literally the number of requests — starting from one — sent over the network connection since it was opened. not zero. one. we start at one in this house. 💅

and more specifically: it's the number that was the value of NextRequest immediately before the failing call was made. so like, the last number before everything went sideways. 😭

🌸 the request_code member, explained 🌸

request_code is a protocol request of the procedure that failed, as defined in X11/Xproto.h. that's it. that's the definition. go read the header, iykyk. 📖✨

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🔥 SEE ALSO 🔥

the whole friend group!! go say hi to literally everyone:

• AllPlanes(3)
• XAnyEvent(3)
• XButtonEvent(3)
• XCreateWindowEvent(3)
• XCirculateEvent(3)
• XCirculateRequestEvent(3)
• XColormapEvent(3)
• XConfigureEvent(3)
• XConfigureRequestEvent(3)
• XCrossingEvent(3)
• XDestroyWindowEvent(3)
• XExposeEvent(3)
• XFocusChangeEvent(3)
• XGraphicsExposeEvent(3)
• XGravityEvent(3)
• XKeymapEvent(3)
• XMapEvent(3)
• XMapRequestEvent(3)
• XPropertyEvent(3)
• XReparentEvent(3)
• XResizeRequestEvent(3)
• XSelectionClearEvent(3)
• XSelectionEvent(3)
• XSelectionRequestEvent(3)
• XUnmapEvent(3)
• XVisibilityEvent(3)

plus the big one: Xlib - C Language X Interface — the mothership, the blueprint, the blueprintiest blueprint. 🌈

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ngl this page is short but it ATE. tiny struct, huge lore. 💀

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okay bye bestie, love u!! this page came to you courtesy of X Version 11 and libX11 1.8.14 — go forth and debug, you absolute icon 🧚💜🎀