TelnetClient example

EthernetServer telnetServer(23);

telnetServer.begin();

Wow this not a way to run both client and server on same machine.

I don't see where telnet comes into place in the TelnetClient example.

Actually now Serial Port your cmd line

while (Serial.available() > 0) {
    char inChar = Serial.read();
    if (client.connected()) {
      client.print(inChar); 
    }
  }