NAME

       io_uring_get_sqe - get the next available submission queue entry from the submission queue

SYNOPSIS

       #include <liburing.h>

       struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring);

DESCRIPTION

       The io_uring_get_sqe(3) function gets the next available submission queue entry from the submission queue
       belonging to the ring param.

       On  success  io_uring_get_sqe(3)  returns  a  pointer  to  the submission queue entry. On failure NULL is
       returned.

       If a submission queue entry is returned, it should be filled out via one of the prep  functions  such  as
       io_uring_prep_read(3) and submitted via io_uring_submit(3).

       Note  that neither io_uring_get_sqe nor the prep functions set (or clear) the user_data field of the SQE.
       If the caller expects io_uring_cqe_get_data(3) or io_uring_cqe_get_data64(3) to return  valid  data  when
       reaping  IO  completions,  either  io_uring_sqe_set_data(3)  or io_uring_sqe_set_data64(3) MUST have been
       called before submitting the request.

RETURN VALUE

       io_uring_get_sqe(3) returns a pointer to the next submission queue event on success and NULL on  failure.
       If  NULL  is  returned, the SQ ring is currently full and entries must be submitted for processing before
       new ones can get allocated.

SEE ALSO

       io_uring_submit(3), io_uring_sqe_set_data(3)

liburing-0.7                                      July 10, 2020                              io_uring_get_sqe(3)