NAME
aio_cancel —
cancel an outstanding asynchronous I/O
operation (REALTIME)
LIBRARY
library “librt”
SYNOPSIS
#include
<aio.h>
int
aio_cancel(int
fildes, struct aiocb *
iocb);
DESCRIPTION
Theaio_cancel()
function 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.
RESTRICTIONS
The
aio_cancel()
function does not cancel asynchronous I/O requests for raw disk devices. The
aio_cancel() function will always return
AIO_NOTCANCELED for file descriptors associated with
raw disk devices.
RETURN VALUES
The aio_cancel() function 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(3).
- [
AIO_ALLDONE] - All of the requests meeting the criteria have finished.
ERRORS
An error return from aio_cancel()
indicates:
- [
EBADF] - fildes is an invalid file descriptor.
SEE ALSO
aio_error(3), aio_read(3), aio_return(3), aio_suspend(3), aio_write(3)
STANDARDS
The aio_cancel() function is expected to
conform to the IEEE Std 1003.2
(“POSIX.2”) standard.
HISTORY
The aio_cancel() function first appeared
in FreeBSD 3.0. The first functional implementation
of aio_cancel() appeared in FreeBSD
4.0.
AUTHORS
This manual page was originally written by Wes
Peters
<wes@softweyr.com>.
Christopher M Sedore
<cmsedore@maxwell.syr.edu>
updated it when aio_cancel() was implemented for
FreeBSD 4.0.