ZMQ sometimes locks up when creating new zmq.Context()

[jez9999]

OK, this has happened to me twice, now. The first time I restarted the PC and it started working again, so it feels like some kind of resource problem where ZMQ has used up all its resources and Windows can't allocate any more, so ZMQ just hangs.

I'm using Windows 7, Node 7.0.0, and ZMQ Node.js bindings 2.15.3.

Basically, things work fine for a while. I am stopping and starting my JS program quite often, and each time it's creating a new ZMQ socket. After a while though (maybe 100 starts of the program? that's just a guess), it starts hanging when I try to create a socket with zmq.socket('sockName'). I debugged it and traced the exact point at which my Node program hangs as index.js line 174:

ctx = new zmq.Context(io_threads);

(io_threads is 1.) Not sure why it hangs here. Why might it? Is there any further debugging I can do to see just what is causing it to hang?