ib_get_ucaps(9)

💖 ib_get_ucaps — the one where you ask "which ucaps are in this fd pile?" 💖

okay so real talk, this is from the Kernel API Manual, section 9 — yes, the big-kid kernel-functions section, main character energy only ✨

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🌸 NAME 🌸

ib_get_ucaps — get a bitmask of ucap types out of a bunch of file descriptors 🎀

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✨ SYNOPSIS ✨

int ib_get_ucaps (int *fds , int fd_count , uint64_t *idx_mask );

that's it, that's the whole vibe check 💅

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🦋 ARGUMENTS 🦋

• fds — an array of file descriptors. like, a whole squad of them 🫶
• fd_count — how many file descriptors are actually in that array. don't lie about this number bestie, it's literally the headcount 😭
• idx_mask — the bitmask that gets updated based on the ucaps living in the fd list. it's the thing you're here to fill in 🌈

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💜 DESCRIPTION 💜

okay so picture this: you hand it an array of file descriptors, and it gives you back a bitmask of the ucaps — where a bit is set if an FD for that ucap type was in the array. that's it. that's the whole function. lowkey iconic 🧚

no cap, it's giving "tell me which ucap types showed up to the party" and honestly? obsessed 🔥

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⭐ RETURN ⭐

0 on success, or a negative errno value on failure. so like, if you see a negative number, something went wrong and you should respectfully panic 💀

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👑 SEE ALSO 👑

• Kernel file ./drivers/infiniband/core/ucaps.c
• ib_ucaps_init(9)
• ib_create_ucap(9)
• ib_remove_ucap(9)

go read those, iykyk 📚✨

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and that's the page bestie!! this one comes straight out of ./drivers/infiniband/core, dated October 2026, and it's filed under ib_get_ucaps(9) — periodt 💅🎀💖