disassociate_ctty(9)

📦 version 7.3.1, in nixpkgs unstable

💅 disassociate_ctty — bestie's guide to yeeting your controlling tty

okay so this one lives in the Kernel API Manual, section 9, and it's literally called disassociate_ctty(9). the whole vibe? disconnect controlling tty. that's it, that's the function 🎀

✨ SYNOPSIS ✨

void disassociate_ctty (int on_exit );

🫶 ARGUMENTS 🫶

  • on_exit — true if you're exiting, meaning we actually need to "hang up" the session. like, fr fr hang it up 👋

🌸 DESCRIPTION 🌸

so this function is typically called only by the session leader, when it wants to disassociate itself from its controlling tty. main character energy only, no cap 💅

here's what it does, bestie — three whole things:

  1. Sends a SIGHUP and SIGCONT to the foreground process group 📣
  2. Clears the tty from being controlling the session 🧹
  3. Clears the controlling tty for all processes in the session group 🌈

the on_exit argument gets set to 1 if it's called when a process is exiting; it's 0 if it's called by the ioctl TIOCNOTTY. iykyk ✨

Locking: BTM is taken for hysterical raisons, and held when called from no_tty. tty_mutex is taken to protect tty → siglock is taken to protect ->signal/->sighand. tasklist_lock is taken to walk process list for sessions → siglock is taken to protect ->signal/->sighand. yes, both of those last two really are in there twice — not me editing the lore 🙈

🦋 SEE ALSO 🦋

Kernel file ./drivers/tty/tty_jobctrl.c

and that's the whole page, bestie 🍓 source lives at ./drivers/tty, dated October 2026, and it's disassociate_ctty(9) forever and always. slay, go touch some tty-less grass 💜👑

📦 where this page comes from