io_uring_prep_timeout_remove(3) — Linux manual page


io_uring_p...eout_update(3)  liburing Manual io_uring_p...eout_update(3)

NAME         top

       io_uring_prep_timeoute_update - prepare a request to update an
       existing timeout

SYNOPSIS         top

       #include <liburing.h>

       void io_uring_prep_timeout_update(struct io_uring_sqe *sqe,
                                         struct __kernel_timespec *ts,
                                         __u64 user_data,
                                         unsigned flags);

       void io_uring_prep_timeout_remove(struct io_uring_sqe *sqe,
                                         __u64 user_data,
                                         unsigned flags);

DESCRIPTION         top

       These functions modify or cancel an existing timeout request. The
       submission queue entry sqe is setup to arm a timeout update or
       removal specified by user_data and with modifier flags given by
       flags.  Additionally, the update request includes a ts structure,
       which contains new timeout information.

       For an update request, the flags member may contain a bitmask of
       the following values:

              The value specified in ts is an absolute value rather than
              a relative one.

              The boottime clock source should be used.

              The realtime clock source should be used.

              Consider an expired timeout a success in terms of the
              posted completion.  Normally a timeout that triggers would
              return in a -ETIME CQE res value.

       The timeout remove command does not currently accept any flags.

RETURN VALUE         top


ERRORS         top

       These are the errors that are reported in the CQE res field. On
       success, 0 is returned.

              The timeout identified by user_data could not be found. It
              may be invalid, or triggered before the update or removal
              request was processed.

              The timeout identified by user_data is already firing and
              cannot be canceled.

              One of the fields set in the SQE was invalid. For example,
              two clocksources where given, or the specified timeout
              seconds or nanoseconds where < 0.

              io_uring was unable to access the data specified by ts.

NOTES         top

       As with any request that passes in data in a struct, that data
       must remain valid until the request has been successfully
       submitted. It need not remain valid until completion. Once a
       request has been submitted, the in-kernel state is stable. Very
       early kernels (5.4 and earlier) required state to be stable until
       the completion occurred. Applications can test for this behavior
       by inspecting the IORING_FEAT_SUBMIT_STABLE flag passed back from

SEE ALSO         top

       io_uring_get_sqe(3), io_uring_submit(3), io_uring_prep_timeout(3)

COLOPHON         top

       This page is part of the liburing (A library for io_uring)
       project.  Information about the project can be found at 
       ⟨⟩.  If you have a bug report for
       this manual page, send it to  This page
       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
       problems in this HTML version of the page, or you believe there
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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_p...eout_update(3)

Pages that refer to this page: io_uring_prep_timeout(3)