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 .