man3/aio_return.3

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  24 .TH AIO_RETURN 3 2015-03-02  "" "Linux Programmer's Manual"
  25 .SH NAME
  26 aio_return \- get return status of asynchronous I/O operation
  27 .SH SYNOPSIS
  28 .B "#include <aio.h>"
  29 .PP
  30 .BI "ssize_t aio_return(struct aiocb *" aiocbp );
  31 .PP
  32 Link with \fI\-lrt\fP.
  33 .SH DESCRIPTION
  34 The
  35 .BR aio_return ()
  36 function returns the final return status for the asynchronous I/O request
  37 with control block pointed to by
  38 .IR aiocbp .
  39 (See
  40 .BR aio (7)
  41 for a description of the
  42 .I aiocb
  43 structure.)
  44 .PP
  45 This function should be called only once for any given request, after
  46 .BR aio_error (3)
  47 returns something other than
  48 .BR EINPROGRESS .
  49 .SH RETURN VALUE
  50 If the asynchronous I/O operation has completed, this function returns
  51 the value that would have been returned in case of a synchronous
  52 .BR read (2),
  53 .BR write (2),
  54 .BR fsync (2)
  55 or
  56 .BR fdatasync (2),
  57 call.
  58 On error, \-1 is returned, and \fIerrno\fP is set appropriately.
  59 .PP
  60 If the asynchronous I/O operation has not yet completed,
  61 the return value and effect of
  62 .BR aio_return ()
  63 are undefined.
  64 .SH ERRORS
  65 .TP
  66 .B EINVAL
  67 .I aiocbp
  68 does not point at a control block for an asynchronous I/O request
  69 of which the return status has not been retrieved yet.
  70 .TP
  71 .B ENOSYS
  72 .BR aio_return ()
  73 is not implemented.
  74 .SH VERSIONS
  75 The
  76 .BR aio_return ()
  77 function is available since glibc 2.1.
  78 .SH ATTRIBUTES
  79 For an explanation of the terms used in this section, see
  80 .BR attributes (7).
  81 .TS
  82 allbox;
  83 lb lb lb
  84 l l l.
  85 Interface       Attribute       Value
  86 T{
  87 .BR aio_return ()
  88 T}      Thread safety   MT-Safe
  89 .TE
  90 .SH CONFORMING TO
  91 POSIX.1-2001, POSIX.1-2008.
  92 .SH EXAMPLE
  93 See
  94 .BR aio (7).
  95 .SH SEE ALSO
  96 .BR aio_cancel (3),
  97 .BR aio_error (3),
  98 .BR aio_fsync (3),
  99 .BR aio_read (3),
 100 .BR aio_suspend (3),
 101 .BR aio_write (3),
 102 .BR lio_listio (3),
 103 .BR aio (7)