tty_unthrottle(9)

💅 tty_unthrottle(9) — Kernel API Manual 🎀

okay bestie, welcome to tty_unthrottle(9)</p> ✨ this one's from the Kernel API Manual and it's short, it's sweet, and it's literally about letting a tty breathe again. 🫶

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✨ NAME ✨

tty_unthrottle — flow control 💖

🌸 SYNOPSIS 🌸

void tty_unthrottle (struct tty_struct *tty );

🦋 ARGUMENTS 🦋

• tty — the terminal 🎀

💜 DESCRIPTION 💜

So here's the vibe: this is you telling a tty “okay queen, you may continue transmitting data down the stack” ✨ it's the un-choke, the release, the go off. 💅

It takes tty_struct->termios_rwsem — yeah, the semaphore — to protect against parallel throttle/unthrottle happening at the same time 😭 and also so the driver can consistently reference its own termios data at this point when it's implementing software flow control. Lowkey important. 🔥

⚠️ Drivers should however remember that the stack can issue a throttle, then change flow control method, then unthrottle. 👀 like, in that order. do not assume anything stays put, fr fr. no cap.

⭐ SEE ALSO ⭐

Kernel file ./drivers/tty/tty_ioctl.c — and also go check out these icons, iykyk:

• tty_chars_in_buffer(9)
• tty_write_room(9)
• tty_driver_flush_buffer(9)
• tty_throttle_safe(9)
• tty_unthrottle_safe(9)
• tty_wait_until_sent(9)
• tty_termios_copy_hw(9)
• tty_termios_hw_change(9)
• tty_get_char_size(9)
• tty_get_frame_size(9)
• tty_set_termios(9)
• set_termios(9)
• set_sgttyb(9)
• tty_change_softcar(9)
• tty_mode_ioctl(9)

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💀 annnnd that's the whole page bestie, she's a short one but she's iconic 👑

🫶 this cutie lives in ./drivers/tty, shipped October 2026 as part of the Kernel API Manual, and yes the title is tty_unthrottle(9) in case you forgot already 🙈 mwah, go unthrottle something 💖✨