io_uring_register_clock(3)

✨ io_uring_register_clock ✨

ok so bestie, this one is a liburing manual page, and it's literally all about telling io_uring which clock to vibe with when it's out here waiting for event completions 🕰️💖

🎀 NAME 🎀

io_uring_register_clock — set the clock source for event waiting. yes that's it, that's the whole job, and it's iconic 💅

🌸 SYNOPSIS 🌸

#include <liburing.h>

int io_uring_register_clock(struct io_uring *ring,
                            struct io_uring_clock_register *arg);

🦋 DESCRIPTION 🦋

okok so the io_uring_register_clock(3) function is the one you call to register which clock source io_uring should use when your app is out here waiting for event completions 🫶

• the ring argument should point at the ring in question (yk, the ring you're doing the thing with)
• and the arg argument should be a pointer to a struct io_uring_clock_register

and like, the arg argument has to be actually filled in with the right info, no being lazy about it. here's what it looks like:

struct io_uring_clock_register {
    __u32 clockid;
    __u32 __resv[3];
};

the clockid field must contain the clock source, and the valid sources are, bestie, drumroll pls 🥁:

• CLOCK_MONOTONIC — a nonsettable system-wide clock that represents monotonic time. no cap, it just goes forward 💫
• CLOCK_BOOTTIME — a nonsettable system-wide clock that is identical to CLOCK_MONOTONIC, except that it also icnludes any time that the system is suspended 😴 (so like, the nap time counts too)

if you want the full lore, go read clock_gettime(3), it has all the deets 📖

and the __resv fields? they must be filled with zeroes. literally zeros, nothing else, don't get cute with it 🙈

Available since 6.12. so if you're on something older, sorry bestie, this is not your era yet 💀

⭐ RETURN VALUE ⭐

• on success, io_uring_register_clock(3) returns 0 — slay, we love a zero 💖
• on failure it returns -errno — sad girl hours 😭

🌈 SEE ALSO 🌈

• clock_gettime(3)
• io_uring_register(2)
• io_uring_wait_cqe(3)
• io_uring_wait_cqe_timeout(3)

and that's the whole page, periodt 🎀 this was liburing-2.8, dated Aug 18, 2024, straight out of the liburing Manual — mwah, go register a clock, you got this 👑💜