v4l2_ctrl_grab(9)

📦 version 7.3.1, in nixpkgs unstable

✨ v4l2_ctrl_grab ✨

Kernel API Manual — yes bestie, we're in the kernel docs now 💅

🌸 NAME 🌸

v4l2_ctrl_grab — mark the control as grabbed or not grabbed 🫶

🎀 SYNOPSIS 🎀

void v4l2_ctrl_grab (struct v4l2_ctrl *ctrl , bool grabbed );

🦋 ARGUMENTS 🦋

  • ctrl — the control you're (de)activating, aka the main character of this whole function 👑
  • grabbed — a bool, and it's giving "yes" energy: pass true when the control should become grabbed 💖

🌈 DESCRIPTION 🌈

okay so here's the tea ☕ — this function sets or clears the V4L2_CTRL_FLAG_GRABBED flag, and it does it atomically. no cap, no race conditions, just clean flag-flipping ✨

It lowkey does nothing if ctrl == NULL, so don't stress about that edge case, it's handled 🙈

Afterwards, the V4L2_EVENT_CTRL event gets generated. so like, the notification is automatic, you don't gotta do it yourself 💅

You'll usually be calling this when you start or stop streaming in the driver — that's the vibe check moment where grabbing makes sense 🎬

⚠️ heads up bestie: this function assumes the control handler is not locked and will take the lock itself. so do not come in here already holding it, or it's gonna be a whole mess 😭

🧚 SEE ALSO 🧚

Kernel file ./include/media/v4l2-ctrls.h — plus the entire friend group, fr fr:

that's the whole page, bestie — go grab some controls 💜

source file lives in ./include/media, dated October 2026, and yeah — this is the v4l2_ctrl_grab(9) page, slay 🎀✨

📦 where this page comes from