aio_cancel — cancel an outstanding asynchronous I/O operation (REALTIME)
Contents
Description
The aio_cancel() system call cancels the outstanding asynchronous I/O request for the file descriptor
specified in fildes. If iocb is specified, only that specific asynchronous I/O request is cancelled.
Normal asynchronous notification occurs for cancelled requests. Requests complete with an error result
of ECANCELED.
Errors
An error return from aio_cancel() indicates:
[EBADF] The fildes argument is an invalid file descriptor.
History
The aio_cancel() system call first appeared in FreeBSD 3.0. The first functional implementation of
aio_cancel() appeared in FreeBSD 4.0.
Library
Standard C Library (libc, -lc)
Name
aio_cancel — cancel an outstanding asynchronous I/O operation (REALTIME)
Restrictions
The aio_cancel() system call does not cancel asynchronous I/O requests for raw disk devices. The
aio_cancel() system call will always return AIO_NOTCANCELED for file descriptors associated with raw disk
devices.
Return Values
The aio_cancel() system call returns -1 to indicate an error, or one of the following:
[AIO_CANCELED]
All outstanding requests meeting the criteria specified were cancelled.
[AIO_NOTCANCELED]
Some requests were not cancelled, status for the requests should be checked with
aio_error(2).
[AIO_ALLDONE]
All of the requests meeting the criteria have finished.
See Also
aio_error(2), aio_read(2), aio_return(2), aio_suspend(2), aio_write(2), aio(4)
Standards
The aio_cancel() system call is expected to conform to the IEEE Std 1003.1 (“POSIX.1”) standard.
Synopsis
#include<aio.h>intaio_cancel(intfildes, structaiocb*iocb);
