SIGDELSET(3P)

💅 SIGDELSET(3P) — the POSIX Programmer's Manual, bestie edition

okay so quick heads up before we even start: this is the POSIX Programmer's Manual page for sigdelset. The Linux implementation of this interface may differ (so like, go check the corresponding Linux manual page for the deets on Linux behavior), or honestly the interface might not even be implemented on Linux at all. 🙈 just so you know.

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✨ NAME ✨

sigdelset — delete a signal from a signal set 🎀

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🌸 SYNOPSIS 🌸

#include <signal.h>

int sigdelset(sigset_t *set, int signo);

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💖 DESCRIPTION 💖

So sigdelset() deletes the individual signal specified by signo from the signal set pointed to by set. that's it. that's the whole job. iconic honestly. 👑

okay but here's the part you actually need to internalize, no cap: applications should call either sigemptyset() or sigfillset() at least once for each object of type sigset_t before doing literally anything else with that object. like, initialize your stuff first, bestie.

and if you don't initialize it that way but you still hand it over as an argument to any of pthread_sigmask(), sigaction(), sigaddset(), sigdelset(), sigismember(), sigpending(), sigprocmask(), sigsuspend(), sigtimedwait(), sigwait(), or sigwaitinfo()?

🚨 the results are undefined. not "kinda weird", not "probably fine" — undefined. don't do it. that's giving chaos main character energy and not in a cute way. 💀

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⭐ RETURN VALUE ⭐

Upon successful completion, sigdelset() shall return 0. otherwise it shall return -1 and set errno to indicate the error. that's the whole deal. 🫶

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🔥 ERRORS 🔥

The sigdelset() function may fail if:

• EINVAL — the signo argument is not a valid signal number, or is an unsupported signal number. ✨

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The following sections are informative.

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🦋 EXAMPLES 🦋

None. (yes, really. nothing here. empty. a whole vibe. 🍓)

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🌈 APPLICATION USAGE 🌈

None. (also nothing! we love a low-effort section 💅)

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🧚 RATIONALE 🧚

None. (the reasoning? not here. not today. 🙈)

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💜 FUTURE DIRECTIONS 💜

None. (the future is unwritten, bestie ✨)

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👑 SEE ALSO 👑

• Section 2.4, Signal Concepts
• pthread_sigmask()
• sigaction()
• sigaddset()
• sigemptyset()
• sigfillset()
• sigismember()
• sigpending()
• sigsuspend()
• The Base Definitions volume of POSIX.1‐2017, <signal.h>

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🎀 COPYRIGHT 🎀

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. (read: the original wins, always, periodt.)

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 .

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okay that's the whole page, you ate that 💖 this was IEEE/The Open Group, 2017, SIGDELSET(3P), signing off — go delete some signals responsibly, bestie 🫶✨