Error in zmq-bindings for Node.js.

pub.js

var NO = 383; 

var zmq = require("zeromq");

var socket = zmq.createSocket("pub");
socket.bind("tcp://127.0.0.1:9000", function() {});

setInterval(function() {
  var b = new Buffer(4);
  b[0] = NO >>> 24;
  b[1] = NO >>> 16;
  b[2] = NO >>> 8;
  b[3] = NO % 256;
  socket.send(b);
}, 1000);

sub.js

var NO = 383;

var zmq = require("zeromq");


var b = new Buffer(4);
b[0] = NO >>> 24;
b[1] = NO >>> 16;
b[2] = NO >>> 8;
b[3] = NO % 256;

var socket = zmq.createSocket("sub");
socket.connect("tcp://127.0.0.1:9000");

socket.subscribe(b.toString("binary"));
socket.on("message", function(msg) {
  console.log(msg);
});