local_inc_and_test(9)

✨ local_inc_and_test(9) ✨

okay so bestie, we're in the Kernel API Manual today and this one is literally the cutest little helper 💖 it's local_inc_and_test(9) and it does exactly what it says on the tin, no cap.

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🌸 NAME 🌸

local_inc_and_test — increment and test 🎀

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🦋 SYNOPSIS 🦋

bool local_inc_and_test (local_t *l );

that's it. that's the whole vibe check. ✨

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💜 ARGUMENTS 💜

• l — pointer to type local_t 🫶 that's the thing getting incremented, she's the main character here.

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👑 DESCRIPTION 👑

okay so here's the tea ☕: this function atomically increments l by 1, and then it returns true if the result is zero, or false for all other cases.

atomic means nobody can sneak in and mess with it halfway through — it's giving locked-in, one-and-done, no interruptions energy 💅

so like:

• result is 0 → true 🔥
• literally anything else → false 💀

that's it, that's the whole function, she's iconic and she knows it 🌈

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⭐ SEE ALSO ⭐

lowkey you should also go look at the kernel file ./arch/x86/include/asm/local.h — that's where the family lives 🏠 and while you're there, say hi to:

• local_sub_and_test(9)
• local_dec_and_test(9)
• local_add_negative(9)
• local_add_return(9)
• local_add_unless(9)

they're all siblings, they all ate, periodt 🍓

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aaaand that's the page bestie 🧚 from the fine folks at ./arch/x86/include/asm, dated October 2026, and yes we are still calling this whole thing local_inc_and_test(9) 💖 mwah, go increment something responsibly 🎀