tty_ldisc_hangup(9)

💖 tty_ldisc_hangup(9) — Kernel API Manual bestie era 💖

okay so welcome to tty_ldisc_hangup(9) from the Kernel API Manual — this is the hangup-reset situation, and we’re gonna make it make sense. 🫶✨

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✨ NAME ✨

tty_ldisc_hangup — hangup ldisc reset. That’s the assignment, and it ate. 💅

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🦋 SYNOPSIS 🦋

void tty_ldisc_hangup (struct tty_struct *tty , bool reinit );

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🎀 ARGUMENTS 🎀

• tty — the tty being hung up 😭🫶
• reinit — whether to re-initialise the tty ✨

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🌸 DESCRIPTION 🌸

Okay so some tty devices reset their termios when they receive a hangup event. In that situation we must also switch back to N_TTY properly before we reset the termios data. Lowkey crucial, no cap. 🦋

Locking: We can take the ldisc mutex as the rest of the code is careful to allow for this. 🔒💅

⚠️ In the pty pair case this occurs in the close path of the tty itself, so we must be careful about locking rules. Locking rules are not a vibe to ignore, bestie.

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🌈 SEE ALSO 🌈

• Kernel file: ./drivers/tty/tty_ldisc.c

Also the whole SEE ALSO friend group, all iconic, all present: tty_register_ldisc(9), tty_unregister_ldisc(9), tty_ldisc_get(9), tty_ldisc_put(9), tty_ldisc_ref_wait(9), tty_ldisc_ref(9), tty_ldisc_deref(9), tty_ldisc_flush(9), tty_set_termios_ldisc(9), tty_ldisc_open(9), tty_ldisc_close(9), tty_ldisc_failto(9), tty_ldisc_restore(9), tty_set_ldisc(9), tty_ldisc_kill(9), tty_reset_termios(9), tty_ldisc_reinit(9), tty_ldisc_setup(9), tty_ldisc_release(9), tty_ldisc_init(9), tty_ldisc_deinit(9). 🌈👑

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shoutout to tty_ldisc_hangup(9), the source at ./drivers/tty, the Kernel API Manual version, and the October 2026 date — mwah, bestie 💋💖