code: function create(sock, options) {
    var socket;
    if(!sock) {
      sock = {port: PORT, host: HOST};
    }
    if(typeof sock.createConnection === 'function') {
      socket = sock.createConnection();
    }else{
      socket = net.createConnection(sock);
    }
    return new Client(socket, options);
  }
docs: Create a new client.
  
  When the first argument is a server reference
  createConnection() is called on the server which returns
  an object that mimics the socket event handling.
  
  @param sock Options for the underlying TCP socket or
  a server reference.
  @param options Client connection options.