debian man page for io_queue_wait

io_queue_wait(2)						     Linux AIO							  io_queue_wait(2)

NAME
       io_queue_wait - Wait for io requests to complete

SYNOPSIS
       #include <errno.h>

       #include <libaio.h>

       int io_queue_wait(io_context_t ctx_id, const struct timespec *timeout);

DESCRIPTION
       Attempts to read an event from the completion queue for the aio_context specified by ctx_id.

RETURN VALUES
       May  return  0  if no events are available and the timeout specified by when has elapsed, where when == NULL specifies an infinite timeout.
       Note that the timeout pointed to by when is relative and will be updated if not NULL and the operation blocks.  Will fail with  -ENOSYS	if
       not implemented.

RETURN VALUES
       On success, io_queue_wait returns 0. Otherwise, -error is return, where error is one of the Exxx values defined in the Errors section.

ERRORS
       EFAULT iocbs referenced data outside of the program's accessible address space.

       EINVAL ctx_id refers to an unitialized aio context, the iocb pointed to by iocbs contains an improperly initialized iocb.

       ENOSYS Not implemented.

SEE ALSO
       io(3),	 io_cancel(3),	  io_fsync(3),	 io_getevents(3),   io_prep_fsync(3),	io_prep_pread(3),   io_prep_pwrite(3),	 io_queue_init(3),
       io_queue_release(3), io_queue_run(3), io_set_callback(3), io_submit(3), errno(3).

Linux 2.4							    2009-06-10							  io_queue_wait(2)