184.108.40.206.2.9 Processing a Specific IoCancel Request Message
The structure and fields of the Specific IoCancel Request message are described in section 220.127.116.11.9.
This message MUST be received only after the CreateFile request-response sequence has been sent, establishing a file handle for I/O on this connection. On receiving this message, the client MUST cancel the I/O operation associated with the device that is identified by the value in the RequestId field. The appropriate device I/O reply message for that RequestId MUST still be sent to the server.
If the IoCancel Request Message has been received by the client and there are no outstanding pending I/O requests, this request MUST be ignored. This applies when the client receives the IoCancel Request after the completion of the I/O request, and after the client receives multiple IoCancel requests.