ws4py provides a :class:`ws4py.manager.WebSocketManager` class that takes care of :class:`ws4py.websocket.WebSocket` instances once they the HTTP upgrade handshake has been performed.

The manager is not compulsory but makes it simpler to track and let them run in your application's process.

When you :meth:`add(websocket) <ws4py.manager.WebSocketManager.add>` a websocket to the manager, the file-descriptor is registered with the manager's poller and the :meth:`opened() <ws4py.websocket.WebSocket.opened>` method on is called.

The manager uses a polling mechanism to dispatch on socket incoming events. Two pollers are implemented, one using the traditionnal :py:mod:`select` and another one based on select.epoll which is used only if available on the system.

The polling is executed in its own thread, it keeps looping until the manager :meth:`stop() <ws4py.websocket.WebSocket.stop>` method.

On every loop, the poller is called to poll for all registered file-descriptors. If any one of them is ready, we retrieve the websocket using that descriptor and, if the websocket is not yet terminated, we call its once method so that the incoming bytes are processed.

If the processing fails in anyway, the manager terminates the websocket and remove it from itself.