__v4l2_ctrl_grab(9)

📦 version 7.3.1, in nixpkgs unstable

💅 __v4l2_ctrl_grab (9) — Kernel API Manual ✨

okay so bestie, welcome to the Kernel API Manual page for __v4l2_ctrl_grab — the unlocked variant of v4l2_ctrl_grab, and yes it's giving "I'm the cool reckless sibling who assumes you already locked the door" 💅

🎀 NAME 🎀

__v4l2_ctrl_grab — the unlocked variant of v4l2_ctrl_grab. lowkey the whole personality in one line, no cap.

🦋 SYNOPSIS 🦋

void __v4l2_ctrl_grab (struct v4l2_ctrl *ctrl , bool grabbed );

literally that's it. two args, zero drama ✨

🌸 ARGUMENTS 🌸

  • ctrl — the control you're about to (de)activate. this is the main character of the story 🎀
  • grabbed — a bool, and it's true if the control should become grabbed. so like, true = grab it, false = nah let it go 🙈

💖 DESCRIPTION 💖

okay so what does it actually do? it sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically. atomic as in nobody can catch it mid-flag-flip, periodt 💅

it does nothing if ctrl == NULL. zero. not a peep. not a crash. iconic behaviour honestly 🫶

afterwards, the V4L2_EVENT_CTRL event will be generated — so like, it doesn't just change the flag and dip, it tells everyone about it too 📣

this will usually be called when starting or stopping streaming in the driver. so it's very much a "we're live now!!" / "okay we're done here" kind of function 🎬

⚠️ BIG CAVEAT ALERT ⚠️ this function assumes that the control handler is locked by the caller. that's the whole deal with the __ prefix, babe — nobody's locking it for you. you promised. you said you'd lock it. 😭

⭐ SEE ALSO ⭐

the squad, the whole squad, and nothing but the squad — starting with the kernel file ./include/media/v4l2-ctrls.h 🧚

and that's the page, bestie!! 💜 this little cutie lives in ./include/media and the manual is dated October 2026 — go lock that handler before you call it, i'm literally begging you 😭🫶✨

📦 where this page comes from