man3/aio_cancel.3

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  23 .TH AIO_CANCEL 3 2003-11-14  "" "Linux Programmer's Manual"
  24 .SH NAME
  25 aio_cancel \- cancel an outstanding asynchronous I/O request
  26 .SH SYNOPSIS
  27 .B "#include <aio.h>"
  28 .sp
  29 .BI "int aio_cancel(int " fd ", struct aiocb *" aiocbp );
  30 .SH DESCRIPTION
  31 The
  32 .BR aio_cancel ()
  33 function attempts to cancel outstanding asynchronous I/O requests
  34 for the file descriptor
  35 .IR fd .
  36 If
  37 .I aiocbp
  38 is NULL, all such requests are canceled.
  39 Otherwise, only the request
  40 described by the control block pointed to by
  41 .I aiocbp
  42 is canceled.
  43 .LP
  44 Normal asynchronous notification occurs for canceled requests.
  45 The request return status is set to \-1, and the request error status
  46 is set to
  47 .BR ECANCELED .
  48 The control block of requests that cannot be canceled is not changed.
  49 .LP
  50 If
  51 .I aiocbp
  52 is not NULL, and
  53 .I fd
  54 differs from the file descriptor with which the asynchronous operation
  55 was initiated, unspecified results occur.
  56 .LP
  57 Which operations are cancellable is implementation-defined.
  58 .\" FreeBSD: not those on raw disk devices.
  59 .SH "RETURN VALUE"
  60 This function returns
  61 .B AIO_CANCELED
  62 if all requests were successfully
  63 canceled.
  64 It returns
  65 .B AIO_NOTCANCELED
  66 when at least one of the
  67 requests specified was not canceled because it was in progress.
  68 In this case one may check the status of individual requests using
  69 .BR aio_error (3).
  70 This function returns
  71 .B AIO_ALLDONE
  72 when all requests had
  73 been completed already before this call.
  74 When some error occurs, \-1 is returned, and
  75 .I errno
  76 is set appropriately.
  77 .SH ERRORS
  78 .TP
  79 .B EBADF
  80 .I fd
  81 is not a valid file descriptor.
  82 .SH "CONFORMING TO"
  83 POSIX.1-2001
  84 .SH "SEE ALSO"
  85 .BR aio_error (3),
  86 .BR aio_fsync (3),
  87 .BR aio_read (3),
  88 .BR aio_return (3),
  89 .BR aio_suspend (3),
  90 .BR aio_write (3)