NAME
aio_return - retrieve return status of an asynchronous I/O operation
(REALTIME)
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(), write(), or fsync() 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(), 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(), write(), and fsync(), shall be
returned. If the asynchronous I/O operation has not yet completed, the
results of aio_return() are undefined.
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.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
The aio_return() function is part of the Asynchronous Input and Output
option and need not be available on all implementations.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
aio_cancel() , aio_error() , aio_fsync() , aio_read() , aio_write() ,
close() , exec() , exit() , fork() , lio_listio() , lseek() , read() ,
the Base Definitions volume of IEEE Std 1003.1-2001, <aio.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online
at http://www.opengroup.org/unix/online.html .