private static void ServerThread(object data)
        {
            pipeServer =
                new NamedPipeServerStream("testpipe", PipeDirection.InOut, numThreads);

            int threadId = Thread.CurrentThread.ManagedThreadId;

            // Wait for a client to connect
            pipeServer.WaitForConnection();

            Console.WriteLine("Client connected on thread[{0}].", threadId);
            try
            {
                // Read the request from the client. Once the client has
                // written to the pipe its security token will be available.

                ss = new StreamString(pipeServer);

                // Verify our identity to the connected client using a
                // string that the client anticipates.

                ss.WriteString("I am the one true server!");
                string filename = ss.ReadString();

                // Read in the contents of the file while impersonating the client.
                ReadFileToStream fileReader = new ReadFileToStream(ss, filename);

                // Display the name of the user we are impersonating.
                Console.WriteLine("Reading file: {0} on thread[{1}] as user: {2}.",
                    filename, threadId, pipeServer.GetImpersonationUserName());
                pipeServer.RunAsClient(fileReader.Start);
            }
            // Catch the IOException that is raised if the pipe is broken
            // or disconnected.
            catch (IOException e)
            {
                Console.WriteLine("ERROR: {0}", e.Message);
            }
        }
 public ReadFileToStream(StreamString str, string filename)
 {
     fn = filename;
     ss = str;
 }