PTHREAD_MULTI_NP(3)

💅 PTHREAD_MULTI_NP(3) — bestie's guide to switching thread modes 🧵✨

okay so this is a page from the Library Functions Manual, and it lives in the POSIX Threads Library — aka libpthread, which you link with -lpthread. no cap, that's the whole vibe. 🫶

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✨ NAME ✨

pthread_multi_np, pthread_single_np — the two functions that let you flip your process between multi-threaded and single-threaded scheduling modes. it's giving "pause the whole group chat" vs "resume the whole group chat", honestly. 🎀

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📚 LIBRARY 📚

POSIX Threads Library (libpthread, -lpthread) — the one and only. 💖

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🌸 SYNOPSIS 🌸

#include <pthread_np.h>

int
pthread_multi_np(void);

int
pthread_single_np(void);

two functions, zero arguments, and they both hand you back an int. simple. iconic. 🔥

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💫 DESCRIPTION 💫

so here's the tea. ☕

• pthread_single_np() — this one switches the whole process into single-threaded mode, which literally means it suspends all threads except the current one. yes, everybody else goes to sleep, you're the main character now. 👑 the semantics of this function are similar to pthread_suspend_all_np(3).
• pthread_multi_np() — and this one switches the process back into multi-threaded mode. everybody wakes up, the party resumes, we're all back in the group chat. 🌈 the semantics of this function are similar to pthread_resume_all_np(3).

that's it, that's the whole thing. no hidden agenda, no secret flags. 🦋

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⭐ RETURN VALUES ⭐

pthread_multi_np() and the pthread_single_np functions always return 0. like, always. they don't do the error thing. zero is the whole personality. 💀✨

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👀 SEE ALSO 👀

• pthread_np(3)
• pthread_resume_all_np(3)
• pthread_suspend_all_np(3)

go read those next, iykyk 📖💜

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🎀 AUTHORS 🎀

this manual page was written by Alexey Zelkin <phantom@FreeBSD.org>. absolute legend behavior, we stan. 🙈💅

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tiny heads up, bestie: pthread_single_np() suspends all your other threads, so like… know what you're doing before you hit that. it's powerful and it's real. 🧚‍♀️

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okay that's the page!! source is Debian, dated October 12, 2021, and it's the PTHREAD_MULTI_NP(3) page — mwah, slayed, periodt. 🍓💖🎀