UNLOCKPT(3P)

📦 version 2017a, in alpine 3.22, alpine 3.23, alpine 3.24, arch rolling, nixpkgs unstable, opensuse-leap 16.0

✨ UNLOCKPT(3P) ✨

okay bestie, we're diving into the POSIX Programmer's Manual, and today's main character is unlockpt — the function that unlocks a pseudo-terminal master/slave pair 🔓💖

🌸 PROLOG 🌸

okay so first things first, bestie, real talk: this manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ — so like, consult the corresponding Linux manual page for the deets on Linux behavior. Also possible: the interface just straight up isn't implemented on Linux. 💀 iykyk, always check your platform.

👑 NAME 👑

unlockpt — unlock a pseudo-terminal master/slave pair 🎀

✨ SYNOPSIS ✨

#include <stdlib.h>

int unlockpt(int fildes);

💅 DESCRIPTION 💅

okay so here's the tea: the unlockpt() function shall unlock the slave pseudo-terminal device associated with the master to which fildes refers. that's it, that's the whole job. slay. 🔥

and this part is important, no cap: conforming applications shall ensure that they call unlockpt() before opening the slave side of a pseudo-terminal device. like, order of operations matters here. unlock first, then open. periodt. 💅

🦋 RETURN VALUE 🦋

  • upon successful completion, unlockpt() shall return 0 ✨
  • otherwise, it shall return -1 and set errno to indicate the error 😭

🌈 ERRORS 🌈

the unlockpt() function may fail if:

  • EBADF — the fildes argument is not a file descriptor open for writing. like bestie, it's giving closed-for-business energy 🙈
  • EINVAL — the fildes argument is not associated with a master pseudo-terminal device. wrong vibes entirely, vibe check failed 💀
the following sections are informative — so they're the commentary track, not the actual rules, okay?

🎀 EXAMPLES 🎀

None.

(nothing to see here bestie, the examples section said "not me" and stayed empty 💖)

🍓 APPLICATION USAGE 🍓

None.

🧚 RATIONALE 🧚

See the RATIONALE section for posix_openpt(). go read that one for the lore, i'm just the messenger 🫶

⭐ FUTURE DIRECTIONS ⭐

None.

🔥 SEE ALSO 🔥

  • grantpt()
  • open()
  • posix_openpt()
  • ptsname()

the Base Definitions volume of POSIX.1‐2017, <stdlib.h> 🌸

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

and that's a wrap, bestie 🎬💖 this edition dropped from IEEE/The Open Group, 2017, and the page is literally called UNLOCKPT(3P). go unlock some pseudo-terminals responsibly, mwah 💅✨

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