v4l2_g_ext_ctrls(9)

📦 version 7.3.1, in nixpkgs unstable

💅 v4l2_g_ext_ctrls(9) — Kernel API Manual ✨

okay so bestie, welcome to the glow-up of v4l2_g_ext_ctrls 💖 this is a page straight out of the Kernel API Manual, and it's genuinely such a slay little helper. sit down, grab a strawberry drink 🍓, and let's get into it.

🌸 NAME 🌸

v4l2_g_ext_ctrls — the helper function that implements the :ref:VIDIOC_G_EXT_CTRLS <vidioc_g_ext_ctrls>`` ioctl 🎀

like, that's the whole vibe. it's the backstage crew making that ioctl happen, iykyk.

✨ SYNOPSIS ✨

int v4l2_g_ext_ctrls (struct v4l2_ctrl_handler *hdl , struct
video_device *vdev , struct media_device *mdev , struct
v4l2_ext_controls *c );

that's the signature, no cap. four pointers in, an int out 💅

🎀 ARGUMENTS 🎀

four besties walk into a function, and here's who they are:

  • hdl — pointer to struct v4l2_ctrl_handler 👑 the main character of the control world, fr fr.
  • vdev — pointer to struct video_device 📹 the video device in question.
  • mdev — pointer to struct media_device 🦋 the media device, keeping the whole media graph cute and connected.
  • c — pointer to struct v4l2_ext_controls 🧚 the extended-controls struct carrying the actual request.

💀 DESCRIPTION 💀

here's the one (1) caveat and it's lowkey dramatic: if hdl == NULL then they will all return -EINVAL 😭

so like… don't pass a NULL handler. seriously. -EINVAL is the vibe check failing and nobody wants that 💀

🌈 SEE ALSO 🌈

the extended fam — genuinely iconic lineup, every single one of them 🫶. first up, the source file:

  • Kernel file ./include/media/v4l2-ctrls.h

then the whole squad, in order:

like… the whole friend group showed up to the party 🎉 obsessed.

that's the page, bestie! and for the cute little sign-off: this one lives in ./include/media 📁, from the October 2026 era, and it's serving v4l2_g_ext_ctrls(9) energy from start to finish. go read some controls, periodt 💜🦋

📦 where this page comes from