io_uring_cqe_nr(3) — Linux manual page

io_uring_cqe_nr(3)           liburing Manual           io_uring_cqe_nr(3)

NAME         top

       io_uring_cqe_nr - return the number of CQ ring slots consumed by a
       CQE

SYNOPSIS         top

       #include <liburing.h>

       unsigned io_uring_cqe_nr(const struct io_uring_cqe *cqe);

DESCRIPTION         top

       The io_uring_cqe_nr(3) function returns the number of CQ ring
       slots consumed by cqe.  For normal 16-byte CQEs, this returns 1.
       For 32-byte CQEs (when IORING_CQE_F_32 is set in the CQE flags),
       this returns 2.

       This function is useful when advancing the CQ ring with
       io_uring_cq_advance(3) on rings that use IORING_SETUP_CQE_MIXED
       where both 16-byte and 32-byte CQEs may be present.

RETURN VALUE         top

       Returns 1 for normal CQEs, or 2 for 32-byte CQEs.

SEE ALSO         top

       io_uring_cq_advance(3), io_uring_cqe_seen(3), io_uring_setup(2)

COLOPHON         top

       This page is part of the liburing (A library for io_uring)
       project.  Information about the project can be found at 
       ⟨https://github.com/axboe/liburing⟩.  If you have a bug report for
       this manual page, send it to io-uring@vger.kernel.org.  This page
       was obtained from the project's upstream Git repository
       ⟨https://github.com/axboe/liburing⟩ on 2026-05-24.  (At that time,
       the date of the most recent commit that was found in the
       repository was 2026-05-18.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there is
       a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

liburing-2.12                January 18, 2025          io_uring_cqe_nr(3)

Pages that refer to this page: io_uring_cqe_nr(3)

HTML rendering created 2026-05-24 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH.