AIO_RETURN(3P)                                      POSIX Programmer's Manual                                     AIO_RETURN(3P)



PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (con-
       sult the corresponding Linux manual page for details of Linux behavior), or the  interface  may  not  be  implemented  on
       Linux.

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  asyn-
       chronous 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  implemen-
       tations.

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, Copy-
       right (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.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                                AIO_RETURN(3P)