Getting Socket options from ZMQ in Node.JS binding

I'm working with the ZMQ binding for Node.js and apparently I cannot access the options of the socket. Here's how I create sockets for PULL and PUSH:

var sender = zmq.socket('push');
var receiver = zmq.socket('pull');

Then it's quite easy to setup a messaging system, but I would like to access _ioevents but it's kind of hard to understand how can I access that option through the socket itself. My aim is to get to the ZMQ_POLLIN and ZMQ_POLLOUT statuses described here. The content of the PULL socket is the following:

{ type: 'pull',
  _zmq: { state: 0, onReady: [Function] },
  _outgoing: [],
  _shouldFlush: true,
  _events: { message: [Function], EINTR: [Function] } }

Which is of no help.

Thanks