NAME
aio_cancel —
cancel an outstanding asynchronous I/O
operation (REALTIME)
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include
<aio.h>
int
aio_cancel(int fildes,
struct aiocb *aiocbp);
DESCRIPTION
The
aio_cancel()
system call cancels the outstanding asynchronous I/O request for the file
descriptor specified in fildes. If
aiocbp 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()
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_ALLDONE] - All of the requests meeting the criteria have finished.
- [
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).
ERRORS
An error return from aio_cancel()
indicates:
- [
EBADF] - The fildes argument is not a valid file descriptor.
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.
HISTORY
The aio_cancel() system call 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.