AIO_RETURN(P)                                                                       AIO_RETURN(P)



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 struc-
       ture referenced by the aiocbp argument. The return status for an asynchronous  I/O  opera-
       tion  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 orig-
       inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .



POSIX                                          2003                                 AIO_RETURN(P)