VOP_IOCTL(9)

✨ NAME ✨

Okay so bestie, welcome to VOP_IOCTL(9) from the Kernel Developer's Manual — the page for device specific control. 💅 This is the VOP_IOCTL vibe, and we're keeping every detail, no cap.

🌸 SYNOPSIS 🌸

#include <sys/param.h>
#include <sys/vnode.h>

int
VOP_IOCTL(struct vnode *vp, u_long command, caddr_t data, int fflag,
    struct ucred *cred, struct thread *td);

💅 DESCRIPTION 💅

This entry point is lowkey how you manipulate a file in device dependent ways. Periodt. ✨

The arguments are, bestie:

• vp — The vnode of the file (normally representing a device). 🫶
• command — The device specific operation to perform. 🎀
• data — Extra data for the specified operation. 🍓
• fflag — Some flags ??? (yes, the original page says exactly that, question marks and all — iykyk). 😭
• cred — The caller's credentials. 🔐
• td — The calling thread. 🧵

Heads up: Most file systems do not implement this entry point. It's giving rare main character energy, ngl. 💀

🔒 LOCKS 🔒

Lock vibe check: The file should not be locked on entry. Like, don't come in already locked, bestie. 🙈

🎀 RETURN VALUES 🎀

If it slays, zero is returned; otherwise you get an appropriate error code. 🌈

And if the ioctl is not recognized or not handled, ENOTTY should be returned. That's the specific one, fr fr. 💅

🦋 SEE ALSO 🦋

• vnode(9) — go read this too, bestie. 🦋

👑 AUTHORS 👑

This manual page was written by Doug Rabson. Iconic. 👑

💌 source/version: Debian · date: July 24, 1996 — that's the cute little footer sign-off, mwah 💋