linux man page for io_cancel

IO_CANCEL(2)						     Linux Programmer's Manual						      IO_CANCEL(2)

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 3.27 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/.

Linux								    2008-06-18							      IO_CANCEL(2)