TIOCSETD(2const)

💅 TIOCSETD(2const) 💅

okay bestie, so this is a page from section 2const of the Linux man-pages — the little corner of the manual that holds the individual ioctl constants so they each get their own glow-up. sit down, grab a boba, and let's talk about line disciplines ✨

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🌸 NAME 🌸

TIOCGETD, TIOCSETD — get or set the line discipline of the terminal

like. the whole vibe of this page. one gets, one sets. iconic behavior honestly 🫶

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📚 LIBRARY 📚

Standard C library (libc, -lc)

that's the one you already link against, no cap, nothing extra to install 🎀

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🧚 SYNOPSIS 🧚

#include <asm/termbits.h>  /* Definition of TIOC*ETD constants */
#include <sys/ioctl.h>

int ioctl(int fd, TIOCGETD, int *argp);
int ioctl(int fd, TIOCSETD, const int *argp);

so it's ioctl(2) but make it terminal line discipline. note that TIOCGETD does not take a const on argp and TIOCSETD does. the compiler is watching you 👀

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✨ DESCRIPTION ✨

🦋 TIOCGETD

Get the line discipline of the terminal.

like, you're asking the terminal "bestie what's your line discipline rn" and it tells you. lowkey the chill one 💖

🔥 TIOCSETD

Set the line discipline of the terminal.

and this one is the main character move — you're telling the terminal what its line discipline is gonna be now. periodt 💅

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🎀 RETURN VALUE 🎀

On success, 0 is returned. on error? -1 is returned, and errno gets set to tell you exactly what went wrong.

so like — 0 = slay, -1 = check errno, it's giving diagnostics 🌈

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👑 SEE ALSO 👑

• ioctl(2)
• ioctl_tty(2)

go read those next, iykyk ⭐

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and that's the whole page bestie!! this one came to you from Linux man-pages 6.20, dated 2026-02-08 — treat it like the little treasure it is 💜💖✨