io_uring_prep_link_timeout(3)   liburing Manual  io_uring_prep_link_timeout(3)

NAME
       io_uring_prep_link_timeout - a timeout request for linked sqes

SYNOPSIS
       #include <liburing.h>

       void io_uring_prep_link_timeout(struct io_uring_sqe *sqe,
                                       struct __kernel_timespec *ts,
                                       unsigned flags);

DESCRIPTION
       The io_uring_prep_link_timeout(3) function prepares a timeout request
       for linked sqes. The submission queue entry sqe is setup a timeout
       specified by ts.  The flags argument holds modifier flags for the
       timeout behaviour of the request.

       The ts argument must be filled in with the appropriate information for
       the timeout. It looks as follows:

           struct __kernel_timespec {
               __kernel_time64_t tv_sec;
               long long tv_nsec;
           };

       The flags argument may contain:

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

       IORING_TIMEOUT_BOOTTIME
              The boottime clock source should be used.

       IORING_TIMEOUT_REALTIME
              The realtime clock source should be used.

       IORING_TIMEOUT_ETIME_SUCCESS
              Consider an expired timeout a success in terms of the posted
              completion.

       It is invalid to create a chain (linked sqes) consisting only of a link
       timeout request. If all the requests in the chain are completed before
       timeout, then the link timeout request gets cancelled. Upon timeout,
       all the uncompleted requests in the chain get cancelled.


RETURN VALUE
       None


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

       -ETIME The specified timeout occurred and triggered the completion
              event.

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

       -EFAULT
              io_uring was unable to access the data specified by ts.

       -ECANCELED
              The timeout was canceled because all submitted requests were
              completed successfully or one of the requests resulted in
              failure.



SEE ALSO
       io_uring_get_sqe(3), io_uring_prep_timeout(3)

liburing-2.4                   January 23, 2023  io_uring_prep_link_timeout(3)