Named pipes communication snip

PipeClient.cs

using Shared;

var pipeClient =
    new NamedPipeClientStream(".", "testpipe",
        PipeDirection.InOut, PipeOptions.None,
        TokenImpersonationLevel.Impersonation);

Console.WriteLine("Connecting to server...\n");
pipeClient.Connect();

var ss = new StreamString(pipeClient);
// Validate the server's signature string.
if (ss.ReadString() == "I am the one true server!")
{
    // The client security token is sent with the first write.
    // Send the name of the file whose contents are returned
    // by the server.
    ss.WriteString("killprocess");
}
else
{
    Console.WriteLine("Server could not be verified.");
}
pipeClient.Close();
// Give the client process some time to display results before exiting.
Thread.Sleep(4000);

PipeServer.cs

using Shared;

await using var pipeServer =
    new NamedPipeServerStream("testpipe", PipeDirection.InOut);

Console.WriteLine("Waiting for connection...");
await pipeServer.WaitForConnectionAsync();

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

    var 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!");
    var message = ss.ReadString();


    // Display the name of the user we are impersonating.
    Console.WriteLine("Message received {0} as user: {1}.",
        message, pipeServer.GetImpersonationUserName());
}
// Catch the IOException that is raised if the pipe is broken
// or disconnected.
catch (IOException e)
{
    Console.WriteLine("ERROR: {0}", e.Message);
}
Console.WriteLine("Disconnecting...");
pipeServer.Close();

StreamString.cs

using System.Text;

namespace Shared;

public class StreamString(Stream ioStream)
{
    private readonly UnicodeEncoding _streamEncoding = new();

    public string ReadString()
    {
        var len = 0;

        len = ioStream.ReadByte() * 256;
        len += ioStream.ReadByte();
        var inBuffer = new byte[len];
        ioStream.ReadExactly(inBuffer, 0, len);

        return _streamEncoding.GetString(inBuffer);
    }

    public int WriteString(string outString)
    {
        var outBuffer = _streamEncoding.GetBytes(outString);
        var len = outBuffer.Length;
        if (len > UInt16.MaxValue)
        {
            len = (int)UInt16.MaxValue;
        }
        ioStream.WriteByte((byte)(len / 256));
        ioStream.WriteByte((byte)(len & 255));
        ioStream.Write(outBuffer, 0, len);
        ioStream.Flush();

        return outBuffer.Length + 2;
    }
}