NAME
        AbortIO - attempt to abort an in-progress I/O request

   SYNOPSIS
        AbortIO(iORequest)
                A1

        VOID AbortIO(struct iorequest *);

   FUNCTION
        Ask a device to abort a previously started iorequest.  this is done
        by calling the device's ABORTIO vector, with your given iorequest.


        AbortIO is a command the device that may or may not grant.  If
        successful, the device will stop processing the iorequest, and
        reply to it earlier than it would otherwise have done.

   NOTE
        AbortIO() does NOT remove() the iorequest from your replyport, or
        wait for it to complete.  After an AbortIO() you must wait normally
        for the reply message before actually reusing the request.

        If a request has already completed when AbortIO() is called, no
        action is taken.

   EXAMPLE
            AbortIO(timer_request);
            WaitIO(timer_request);
            /* message is free to be reused */

   INPUTS
        iORequest - pointer to an I/O request block (must have been used
                at least once.  May be active or finished).

   SEE ALSO
        waitio(), doio(), sendio(), checkio()