title: How does zmq poller work?
body: <p>I am confused as to what poller actually does in zmq. The zguide goes into it minimally, and only describes it as a way to read from multiple sockets. This is not a satisfying answer for me because it does not explain how to have timeout sockets. I know <a href="https://stackoverflow.com/questions/7538988/zeromq-how-to-prevent-infinite-wait">zeromq: how to prevent infinite wait?</a> explains for push/pull, but not req/rep patterns, which is what I want to know how to use.</p>
  
  <p>What I am attempting to ask is: How does poller work, and how does its function apply to keeping track of sockets and their requests?</p>