xcb_create_gc(3)

📦
version 1.17.0 · 4 versions
, in alpine 3.22, alpine 3.23, alpine 3.24, arch rolling, centos-stream 10, debian trixie, fedora 43, fedora 44, nixpkgs unstable, opensuse-leap 16.0, ubuntu questing, ubuntu resolute, ubuntu stonking

💅 NAME 💅

xcb_create_gc — bestie, it creates a graphics context. that's the whole vibe. ✨

🎀 SYNOPSIS 🎀

first things first, you gotta pull in the header:

#include <xcb/xproto.h>

✨ Request function ✨

xcb_void_cookie_t xcb_create_gc(xcb_connection_t *conn,
       xcb_gcontext_t cid, xcb_drawable_t drawable, uint32_t value_mask,
       const void *value_list);

🦋 REQUEST ARGUMENTS 🦋

  • conn — your XCB connection to X11. the group chat with the X server, basically.
  • cid — the ID you'll use to refer to this graphics context later. you make it with xcb_generate_id. so iconic of you.
  • drawable — the drawable it's gonna grab the root/depth from.
  • value_mask — TODO: NOT YET DOCUMENTED. 😭 yeah bestie, the docs left us on read.
  • value_list — TODO: NOT YET DOCUMENTED. 🙈 same energy, no cap.

🌸 DESCRIPTION 🌸

so it creates a graphics context. that's it, that's the whole thing. 🫶

and here's the lil rule you cannot skip: the graphics context can be used with any drawable that has the same root and depth as the specified drawable. same root, same depth, or it's not gonna work. periodt. 💅

🌈 RETURN VALUE 🌈

it hands you back an xcb_void_cookie_t. so like, if errors pop off (and they might 👀), you have to deal with them in the event loop. that's just how void cookies work, iykyk.

but if you'd rather handle errors directly with xcb_request_check instead — totally valid — then use xcb_create_gc_checked. see xcb-requests(3) for the details, bestie. ✨

💀 ERRORS 💀

these are the ones that can show up, and yes some of them are literally undocumented, we don't make the rules:

  • xcb_alloc_error_t — the X server could not allocate the requested resources (no memory? 😭).
  • xcb_drawable_error_t — the specified drawable (Window or Pixmap) does not exist. it's giving ghosted.
  • xcb_font_error_t — TODO: reasons? 🤷
  • xcb_match_error_t — TODO: reasons? 🤷
  • xcb_pixmap_error_t — TODO: reasons? 🤷
  • xcb_value_error_t — TODO: reasons? 🤷

👑 SEE ALSO 👑

💜 AUTHOR 💜

generated from xproto.xml. for corrections and improvements, contact xcb@lists.freedesktop.org. they're the ones to dm, not me. 🫶

okay and the lil sign-off so you have the receipts: this is X Version 11, libxcb 1.17.0, and this whole page is xcb_create_gc(3). slay, go make some graphics contexts, bestie. 🎀✨🦋

📦 where this page comes from