1 .\" Copyright (C) 2003 Free Software Foundation, Inc.
2 .\" This file is distributed according to the GNU General Public License.
3 .\" See the file COPYING in the top level source directory for details.
5 .TH IO_CANCEL 2 2012-05-08 "Linux" "Linux Programmer's Manual"
7 io_cancel \- cancel an outstanding asynchronous I/O operation
10 .BR "#include <linux/aio_abi.h>" " /* Defines needed types */"
12 .BI "int io_cancel(aio_context_t " ctx_id ", struct iocb *" iocb ,
13 .BI " struct io_event *" result );
20 attempts to cancel an asynchronous I/O operation previously submitted with
24 argument is the AIO context ID of the operation to be canceled.
25 If the AIO context is found, the event will be canceled and then copied
26 into the memory pointed to by \fIresult\fP without being placed
27 into the completion queue.
32 For the failure return, see NOTES.
36 The \fIiocb\fP specified was not canceled.
39 One of the data structures points to invalid data.
42 The AIO context specified by \fIctx_id\fP is invalid.
46 is not implemented on this architecture.
49 The asynchronous I/O system calls first appeared in Linux 2.5.
53 is Linux-specific and should not be used
54 in programs that are intended to be portable.
56 Glibc does not provide a wrapper function for this system call.
57 You could invoke it using
59 But instead, you probably want to use the
61 wrapper function provided by
62 .\" http://git.fedorahosted.org/git/?p=libaio.git
67 wrapper function uses a different type
69 .\" But glibc is confused, since <libaio.h> uses 'io_context_t' to declare
76 wrapper does not follow the usual C library conventions for indicating errors:
77 on error it returns a negated error number
78 (the negative of one of the values listed in ERRORS).
79 If the system call is invoked via
81 then the return value follows the usual conventions for
82 indicating an error: \-1, with
84 set to a (positive) value that indicates the error.