title: ZeroMQ: Same context for multiple sockets
body: <p>I am trying to use ZeroMQ's pub-sub sockets. However, I don't clearly understand the role of context (<code>zmq::context_t</code>) while creating sockets (<code>zmq::socket_t</code>). </p>
  
  <p>Assuming that I want to create 5 subscriber sockets (<code>zmq::socket_t</code> using <code>ZMQ_SUB</code>), do I need 5 contexts, one for each of the subscriber sockets? Or can I use a single context for all 5 sockets?</p>