log.ext

> node test.js
worker ID:1 got message. message-1
worker ID:0 got message. message-1
worker ID:1 got message. message-2
worker ID:0 got message. message-2

test.js

var cluster = require('cluster');
var http = require('http');
var numReqs = 0;

if (cluster.isMaster) {
  var workers = {};

  // Fork two workers onto their own thread
  for (var i = 0; i < 2; i++) {
    var worker = cluster.fork();
    workers[i] = worker;

    (function (i) {
      worker.on('message', function(msg) {
        // is internal
        if (msg.cmd) return;

        console.log('worker ID:' + i + ' got message.', msg);
      });
    })(i);
  }

}
else {
  // If the worker is not the master process, run it as an HTTP server
  http.Server(function(req, res) {
    res.writeHead(200);
    res.end("hello world\n");
  }).listen(process.env.PORT || 8080, "0.0.0.0");

  process.send('message-1');
  setTimeout(function () {
    process.send('message-2');
  }, 500);
}