PAPI_register_thread(3)

💅 PAPI_register_thread(3) — the PAPI manual, bestie edition

okay so real talk, this page lives in the PAPI manual section 3, and it's about telling PAPI "hey, there's a thread here" 👋

✨ NAME ✨

PAPI_register_thread — the lil function you call to notify PAPI that a thread has 'appeared' 🫶

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🌸 SYNOPSIS 🌸

the C interface, periodt

#include <papi.h>
int PAPI_register_thread (void);

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🦋 DESCRIPTION 🦋

so here's the vibe: you call PAPI_register_thread() when you, the user, want to force PAPI to initialize a thread that PAPI has not seen before. like, you're introducing your thread to PAPI at the party 💅 "PAPI, this is Thread. Thread, PAPI."

usually this is not necessary, ngl — PAPI implicitly detects the thread when an eventset is created, or when other thread local PAPI functions are called. it just kind of knows. main character detection energy ✨

however, it can be useful for debugging and performance enhancements in the run-time systems of performance tools. so like, niche but iconic 🎀

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⭐ Return values ⭐

• PAPI_ENOMEM — space could not be allocated to store the new thread information 😭 the memory said no.
• PAPI_ESYS — a system or C library call failed inside PAPI. check the errno variable, bestie, that's where the tea is 🍓
• PAPI_ECMP — hardware counters for this thread could not be initialized 💀 that's a whole situation.

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👑 See also 👑

• PAPI_unregister_thread — the goodbye counterpart 🥲
• PAPI_thread_id
• PAPI_thread_init

iykyk, go read those next, they're literally the friend group of this function 🌈

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💜 Author 💜

Generated automatically by Doxygen for PAPI from the source code. no human wrote this one, it's giving robot au pair 🤖✨

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fr fr, remember: every detail up there matters, especially the return values — don't sleep on errno when PAPI_ESYS shows up 🙈

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and that's the page, gorgeous 💖 this was Version 7.2.0.0, dated Wed Jun 25 2025 19:30:48 — slay, go register some threads 🧚‍♀️🎀