NAME
aio_return —
retrieve return status of an asynchronous I/O
operation
SYNOPSIS
#include
<aio.h>
ssize_t aio_return(struct aiocb *aiocbp);
DESCRIPTION
The aio_return () function shall return
the return status associated with the aiocb structure
referenced by the aiocbp argument. The return status for
an asynchronous I/O operation is the value that would be returned by the
corresponding read(3), write(3), or
fsync(3) function call. If the error status for the
operation is equal to [EINPROGRESS], then the return status for the
operation is undefined. The aio_return () function
may be called exactly once to retrieve the return status of a given
asynchronous operation; thereafter, if the same aiocb
structure is used in a call to aio_return () or
aio_error(3), an error may be returned. When the
aiocb structure referred to by aiocbp is
used to submit another asynchronous operation, then
aio_return () may be successfully used to retrieve
the return status of that operation.
RETURN VALUE
If the asynchronous I/O operation has completed, then the return
status, as described for read(3),
write(3), and fsync(3), shall be
returned. If the asynchronous I/O operation has not yet completed, the
results of aio_return () are undefined.
If the aio_return () function
fails, it shall return -1 and set
errno to indicate
the error.
ERRORS
The aio_return () function may fail
if:
- [EINVAL]
- The aiocbp argument does not refer to an asynchronous operation whose return status has not yet been retrieved.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
aio_cancel(3), aio_error(3), aio_fsync(3), aio_read(3), aio_write(3), close(3), exec(3), exit(3), fork(3), lio_listio(3), lseek(3), read(3)
XBD <aio.h>
CHANGE HISTORY
First released in Issue 5. Included for alignment with the POSIX Realtime Extension.
Issue 6
The [ENOSYS] error condition has been removed as stubs need not be provided if an implementation does not support the Asynchronous Input and Output option.
The APPLICATION USAGE section is added.
The [EINVAL] error condition is made optional. This is for consistency with the DESCRIPTION.
Issue 7
SD5-XSH-ERN-148 is applied.
The aio_return () function is moved from
the Asynchronous Input and Output option to the Base.