text: const net = require('net');
  
  const port = process.argv[2];
  
  function zerofill(i) {
      return (i < 10 ? '0' : '') + i;
  }
  
  function now() {
      let date = new Date();
      let Y = date.getFullYear();
      let M = zerofill(date.getMonth() +1); // zero based!
      let d = zerofill(date.getDate());
      let h = zerofill(date.getHours());
      let m = zerofill(date.getMinutes());
      let s = zerofill(date.getSeconds());
      return Y + '-' + M + '-' + d + ' ' + h + ':' + m;
  }
  const server = net.createServer(function (socket) {
      socket.end(now() + '\n');
  });
  server.listen(port);
  