Function io_uring_submit_and_wait 

pub unsafe extern "C" fn io_uring_submit_and_wait(
    ring: *mut io_uring,
    wait_nr: c_uint,
) -> c_int

Submit requests to the submission queue and wait for completion

DESCRIPTION

The io_uring_submit_and_wait function submits the next requests from the submission queue belonging to the ring and waits for wait_nr completion events.

After the caller retrieves a submission queue entry (SQE) with io_uring_get_sqe and prepares the SQE, it can be submitted with io_uring_submit_and_wait.

Ideally used with a ring setup with IORING_SETUP_SINGLE_ISSUER|IORING_SETUP_DEFER_TASKRUN as that will greatly reduce the number of context switches that an application will see waiting on multiple requests.

RETURN VALUE

On success io_uring_submit_and_wait returns the number of submitted submission queue entries. On failure it returns -errno.

SEE ALSO

io_uring_queue_init_params, io_uring_get_sqe, io_uring_submit, io_uring_submit_and_wait_timeout