client.js

var net = require('net');

function connect_server(cb){
  var conn = net.createConnection(8006,cb);
  conn.setEncoding('utf8');
  return conn;
}

var conn = connect_server(function(){
 conn.write("msg1");

 conn.addListener("data",function(data){
   conn.write("msg2",function(){
    conn.write("msg3");
   });
 });


});

output

got message: msg1
got message: msg2msg3

server.js

var net = require('net');


var server = net.createServer(function(socket){

  socket.setTimeout(0);
  socket.setEncoding("utf8");
  

  socket.addListener("data", function(rawData){
    if(rawData == 'msg1'){
      socket.write('msg-server');
    }
    console.log('got message:',rawData);
  });
});
server.listen(8006);