aio_cancel

AIO_CANCEL(3)              Linux Programmer's Manual             AIO_CANCEL(3)

NAME
       aio_cancel - cancel an outstanding asynchronous I/O request

SYNOPSIS
       #include <aio.h>

       int aio_cancel(int fd, struct aiocb *aiocbp);

       Link with -lrt.

DESCRIPTION
       The  aio_cancel()  function attempts to cancel outstanding asynchronous
       I/O requests for the file descriptor fd.  If aiocbp is NULL,  all  such
       requests  are  canceled.   Otherwise, only the request described by the
       control block pointed to by aiocbp is canceled.  (See aio(7) for a  de-
       scription of the aiocb structure.)

       Normal  asynchronous  notification  occurs  for  canceled requests (see
       aio(7) and sigevent(7)).  The request return status (aio_return(3))  is
       set  to -1, and the request error status (aio_error(3)) is set to ECAN-
       CELED.  The control block of requests that cannot be  canceled  is  not
       changed.

       If  the  request  could  not be canceled, then it will terminate in the
       usual way after performing the I/O operation.  (In this  case,  aio_er-
       ror(3) will return the status EINPROGRESSS.)

       If  aiocbp  is  not  NULL, and fd differs from the file descriptor with
       which the asynchronous operation was initiated, unspecified results oc-
       cur.

       Which operations are cancelable is implementation-defined.

RETURN VALUE
       The aio_cancel() function returns one of the following values:

       AIO_CANCELED
              All requests were successfully canceled.

       AIO_NOTCANCELED
              At  least one of the requests specified was not canceled because
              it was in progress.  In this case, one may check the  status  of
              individual requests using aio_error(3).

       AIO_ALLDONE
              All requests had already been completed before the call.

       -1     An  error  occurred.  The cause of the error can be found by in-
              specting errno.

ERRORS
       EBADF  fd is not a valid file descriptor.

       ENOSYS aio_cancel() is not implemented.

VERSIONS
       The aio_cancel() function is available since glibc 2.1.

ATTRIBUTES
       For an  explanation  of  the  terms  used  in  this  section,  see  at-
       tributes(7).

       +-------------+---------------+---------+
       |Interface    | Attribute     | Value   |
       +-------------+---------------+---------+
       |aio_cancel() | Thread safety | MT-Safe |
       +-------------+---------------+---------+
CONFORMING TO
       POSIX.1-2001, POSIX.1-2008.

EXAMPLE
       See aio(7).

SEE ALSO
       aio_error(3), aio_fsync(3), aio_read(3), aio_return(3), aio_suspend(3),
       aio_write(3), lio_listio(3), aio(7)

COLOPHON
       This page is part of release 5.05 of the Linux  man-pages  project.   A
       description  of  the project, information about reporting bugs, and the
       latest    version    of    this    page,    can     be     found     at
       https://www.kernel.org/doc/man-pages/.

                                  2015-03-02                     AIO_CANCEL(3)