io_uring_peek_cqe(3) — Linux manual page


io_uring_peek_cqe(3)         liburing Manual        io_uring_peek_cqe(3)

NAME         top

       io_uring_peek_cqe - check if an io_uring completion event is

SYNOPSIS         top

       #include <liburing.h>

       int io_uring_peek_cqe(struct io_uring *ring,
                             struct io_uring_cqe **cqe_ptr);

DESCRIPTION         top

       The io_uring_peek_cqe(3) function returns an IO completion from
       the queue belonging to the ring param, if one is readily
       available. On successful return, cqe_ptr param is filled with a
       valid CQE entry.

       This function does not enter the kernel to wait for an event, an
       event is only returned if it's already available in the CQ ring.

RETURN VALUE         top

       On success io_uring_peek_cqe(3) returns 0 and the cqe_ptr
       parameter is filled in. On failure it returns -EAGAIN.

SEE ALSO         top

       io_uring_submit(3), io_uring_wait_cqes(3), io_uring_wait_cqe(3)

COLOPHON         top

       This page is part of the liburing (A library for io_uring)
       project.  Information about the project can be found at 
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       was obtained from the project's upstream Git repository
       ⟨⟩ on 2023-12-22.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2023-12-19.)  If you discover any rendering
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       (which is not part of the original manual page), send a mail to

liburing-2.2                 March 12, 2022         io_uring_peek_cqe(3)

Pages that refer to this page: io_uring_setup(2)io_uring_cq_advance(3)io_uring_cqe_seen(3)io_uring_peek_cqe(3)