3.3.5.2.2.3 Sending a Read Request Message
The structure and fields of the Read Request message are described in section 2.2.2.3.3.
This message MUST be sent only after the CreateFile request-response sequence has been sent, establishing a file handle for I/O on this connection. The server MUST generate a unique RequestId for this request and specify the number of bytes to read. The server also stores all necessary information required to complete the request (for example, a data buffer to store information and the location of a variable to store the result), and associates this information with the RequestId.