title: How many instances of one class is there on server?
body: <p>Is it possible to know how many instanced objects of one PHP class there is <strong>on whole server</strong> (for all users, not just for one thread).</p>
  
  <p>Here is reason why I want to do it. I am making a card game and I want to have Room class (with unique room name, players at the moment online in room, socked id ...) so when some user join server to have fresh list of active rooms. And when one room is canceled (destroyed) I would send to all users that information (basically real-time Room(s) status).</p>
  
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  <p>Ok, here is reason why I want to do it. 
  I am making card game project and I want to have Room class (with unique room name, players at the moment online in room, socked id ...) so when some user join server to have fresh list of active rooms. And when one room is canceled(destroyed) I would send to all users that information ( basically real-time Room(s) status ). I hope you understand what I want to do.</p>