futex_set(9)

💅 futex_set(9) — your new fave kernel API page

okay so before we even start: this is from the Kernel API Manual, bestie. That's the vibe. Buckle up 🎀

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✨ NAME ✨

futex_set — atomic decrement of the futex value

not me noticing the NAME says "decrement" while the function is literally called set 😭 that's the page, that's what it says, we report, we don't editorialise. iykyk.

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🌸 SYNOPSIS 🌸

u_int32_t futex_set (futex_t *uaddr , u_int32_t newval );

like… look at her. she's taking a futex_t * and a u_int32_t and handing you back a u_int32_t. main character energy honestly 🔥

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🦋 ARGUMENTS 🦋

• uaddr — the address of the futex to be modified. literally where the futex lives. point her in the right direction, bestie 🫶
• newval — New value for the atomic_t. this is the glow-up value you're assigning, no cap ✨

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👑 DESCRIPTION 👑

Return the new futex value.

that's it. that's the whole description. short king behaviour 💀 she said "my job here is done" and left the group chat. we respect it. 🙈

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🌈 SEE ALSO 🌈

the whole futex friend group, assembled 🧚‍♀️✨ first the kernel file:

• Kernel file ./tools/testing/selftests/futex/include/futextest.h

and then the ensemble cast, periodt:

• futex(9)
• futex_wait(9)
• futex_wake(9)
• futex_wait_bitset(9)
• futex_wake_bitset(9)
• futex_lock_pi(9)
• futex_unlock_pi(9)
• futex_wake_op(9)
• futex_requeue(9)
• futex_cmp_requeue(9)
• futex_wait_requeue_pi(9)
• futex_cmp_requeue_pi(9)
• futex_cmpxchg(9)
• futex_dec(9)
• futex_inc(9)

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💖 sign-off 💖

this iconic little page is sourced from ./tools/testing/selftests/fute... and it's dated October 2026, and the whole thing is filed under futex_set(9). slay, go read your futexes, ily 🍓💜

ok one last thing because i have to be that friend: everything above is exactly what the page says — i'm not adding behaviour, i'm not subtracting behaviour. copy the flags, keep the facts, and take care of your futexes fr fr 💅