NAME
io_cancel - cancel an outstanding asynchronous I/O operation
SYNOPSIS
#include <libaio.h>
int io_cancel(aio_context_t ctx_id, struct iocb *iocb,
struct io_event *result);
Link with -laio.
DESCRIPTION
io_cancel() attempts to cancel an asynchronous I/O operation previously
submitted with io_submit(2). ctx_id is the AIO context ID of the
operation to be canceled. If the AIO context is found, the event will
be canceled and then copied into the memory pointed to by result
without being placed into the completion queue.
RETURN VALUE
On success, io_cancel() returns 0. For the failure return, see NOTES.
ERRORS
EAGAIN The iocb specified was not canceled.
EFAULT One of the data structures points to invalid data.
EINVAL The AIO context specified by ctx_id is invalid.
ENOSYS io_cancel() is not implemented on this architecture.
VERSIONS
The asynchronous I/O system calls first appeared in Linux 2.5, August
2002.
CONFORMING TO
io_cancel() is Linux-specific and should not be used in programs that
are intended to be portable.
NOTES
Glibc does not provide a wrapper function for this system call.
The wrapper provided in libaio for io_cancel() does not follow the
usual C library conventions for indicating error: on error it returns a
negated error number (the negative of one of the values listed in
ERRORS). If the system call is invoked via syscall(2), then the return
value follows the usual conventions for indicating an error: -1, with
errno set to a (positive) value that indicates the error.
SEE ALSO
io_destroy(2), io_getevents(2), io_setup(2), io_submit(2)
COLOPHON
This page is part of release 3.24 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.