Node.js tcp client and server example

nodejs-tcp-example.js

/**
 env SERVER=1 node 3.js
 http://joxi.ru/n2YYBPdcjnbK42
 http://joxi.ru/DmB74bJFN8JoB2
 */

/*
 In the node.js intro tutorial (http://nodejs.org/), they show a basic tcp
 server, but for some reason omit a client connecting to it.  I added an
 example at the bottom.
 Save the following server in example.js:
 */
var path = require('path');
var fs = require('fs');
var PATH = '\\\\.\\pipe\\' + /*process.cwd(),*/ 'myctl'; //  '/tmp/3.test.sock'

var net = require('net');

if (process.env.SERVER) {
  if (fs.existsSync(PATH)) {
    console.log('remove...');
    fs.unlinkSync(PATH);
  }
  var server = net.createServer(function (socket) {
    socket.on('data', function(data) {
      console.log('server: ' + data);
      //client.destroy(); // kill client after server's response
    });
    socket.write('Echo server\r\n');
    //socket.pipe(socket);
  });

  console.log('starting...', PATH);
  //server.listen(1337, '192.168.88.108');
  server.listen(PATH);

}

/*
 And connect with a tcp client from the command line using netcat, the *nix
 utility for reading and writing across tcp/udp network connections.  I've only
 used it for debugging myself.
 $ netcat 127.0.0.1 1337
 You should see:
 > Echo server
 */

/* Or use this example tcp client written in node.js.  (Originated with
 example code from
 http://www.hacksparrow.com/tcp-socket-programming-in-node-js.html.) */

var net = require('net');

var client = new net.Socket();
var t1 = process.hrtime();
//client.connect(1337, '192.168.88.108', function() {
client.connect(PATH, function() {
  console.log('Connected');
  client.write('Hello, server! Love, Client.');
});

client.on('data', function(data) {
  console.log('Received: ' + data);
  const t2 = process.hrtime(t1);
  console.log('from connect to recieve: ', t2[0], 's ', t2[1] / 1000000, ' ms');
  client.destroy(); // kill client after server's response
});

client.on('close', function() {
  console.log('Connection closed');
});

I just show UNIX pipe work