video_usercopy(9)

🎀 NAME 🎀

okay bestie, this is video_usercopy(9) from the Kernel API Manual — the routine that copies data from/to userspace memory when an ioctl is issued. 💅✨

✨ SYNOPSIS ✨

here's the exact signature, no cap — do not freestyle it:

long int video_usercopy (struct file *file , unsigned int cmd , unsigned
long int arg , v4l2_kioctl func );

🦋 ARGUMENTS 🦋

okay so the cast of characters is:

• file — a pointer to struct file. 🗂️
• cmd — the ioctl name. 👑
• arg — the ioctl argument. 🎀
• func — the function that will handle the ioctl. 💖

🌈 DESCRIPTION 🌈

okay so here's the important part, bestie: this routine is a V4L2-core-only situation. fr fr. 🫶

💀 NOTE: This routine should be used only inside the V4L2 core.

that's the whole description, and it's highkey important — no outside-the-core shenanigans, periodt. ✨

🎀 SEE ALSO 🎀

go peek at these icons when you're done:

• Kernel file ./include/media/v4l2-ioctl.h struct v4l2_ioctl_ops(9)
• v4l2_norm_to_name(9)
• v4l2_video_std_frame_period(9)
• v4l2_video_std_construct(9)
• v4l_video_std_enumstd(9)
• v4l_printk_ioctl(9)
• var v4l2_field_names(9)
• var v4l2_type_names(9)
• v4l2_compat_ioctl32(9)
• v4l2_kioctl(9)
• video_ioctl2(9)

okay bestie, that's the page! 🫶 source/version: ./include/media • date: October 2026 • video_usercopy(9) signing off! 💖✨