nodejs_socket_json_client.js

var net = require('net');
var fs = require('fs');

var tmp;

fs.readdir('/', function (err, files) {
  //files.forEach(function (file) {
  //});
  tmp = JSON.stringify(files);
});

var client = new net.Socket();
client.connect(3303,'127.0.0.1', function () {
  client.write('{ "command": "hello", "data": '+tmp+'}');
  client.destroy();
});