Sun Microsystems, Inc. gratefully acknowledges The Open Group for
permission to reproduce portions of its copyrighted documentation.
Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.
The Institute of Electrical and Electronics Engineers and The Open
Group, have given us permission to reprint portions of their
documentation.
In the following statement, the phrase ``this text'' refers to portions
of the system documentation.
Portions of this text are reprinted and reproduced in electronic form
in the SunOS Reference Manual, from IEEE Std 1003.1, 2004 Edition,
Standard for Information Technology -- Portable Operating System
Interface (POSIX), The Open Group Base Specifications Issue 6,
Copyright (C) 2001-2004 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy
between these versions 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.
This notice shall appear on any product containing this material.
The contents of this file are subject to the terms of the
Common Development and Distribution License (the "License").
You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
or http://www.opensolaris.org/os/licensing.
See the License for the specific language governing permissions
and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each
file and include the License file at usr/src/OPENSOLARIS.LICENSE.
If applicable, add the following below this CDDL HEADER, with the
fields enclosed by brackets "[]" replaced with your own identifying
information: Portions Copyright [yyyy] [name of copyright owner]
Copyright 1989 AT&T
Portions Copyright (c) 1992, X/Open Company Limited All Rights Reserved
Copyright (c) 2008 Sun Microsystems, Inc. All Rights Reserved.
#include <aio.h> int aio_cancel(int fildes, struct aiocb *aiocbp);
The aio_cancel() function attempts to cancel one or more asynchronous I/O requests currently outstanding against file descriptor fildes. The aiocbp argument points to the asynchronous I/O control block for a particular request to be canceled. If aiocbp is NULL, then all outstanding cancelable asynchronous I/O requests against fildes are canceled.
Normal asynchronous notification occurs for asynchronous I/O operations that are successfully canceled. If there are requests that cannot be canceled, then the normal asynchronous completion process takes place for those requests when they are completed.
For requested operations that are successfully canceled, the associated error status is set to ECANCELED and the return status is -1. For requested operations that are not successfully canceled, the aiocbp is not modified by aio_cancel().
If aiocbp is not NULL, then if fildes does not have the same value as the file descriptor with which the asynchronous operation was initiated, unspecified results occur.
The aio_cancel() function returns the value AIO_CANCELED to the calling process if the requested operation(s) were canceled. The value AIO_NOTCANCELED is returned if at least one of the requested operation(s) cannot be canceled because it is in progress. In this case, the state of the other operations, if any, referenced in the call to aio_cancel() is not indicated by the return value of aio_cancel(). The application may determine the state of affairs for these operations by using aio_error(3C). The value AIO_ALLDONE is returned if all of the operations have already completed. Otherwise, the function returns -1 and sets errno to indicate the error.
The aio_cancel() function will fail if: EBADF
The fildes argument is not a valid file descriptor.
The aio_cancel() function is not supported.
The aio_cancel() function has a transitional interface for 64-bit file offsets. See lf64(5).
See attributes(5) for descriptions of the following attributes:
| ATTRIBUTE TYPE ATTRIBUTE VALUE |
| Interface Stability Committed |
| MT-Level MT-Safe |
| Standard See standards(5). |
aio.h(3HEAD), signal.h(3HEAD), aio_read(3C), aio_return(3C), attributes(5), lf64(5), standards(5)
Solaris 2.6 was the first release to support the Asynchronous Input and Output option. Prior to this release, this function always returned -1 and set errno to ENOSYS.