li>
</ul>
This mechanism ensures that the handler is not deleted until the final
upcall thread exits the handler.
<p>Reference counting on handlers is optional and is disabled by default.
To enable reference counting on a handler, reset its reference counting
policy to "ENABLED".
<p>To facilitate reference counting of handlers, an ACE_Event_Handler_var
class was added. This class is akin to the PortableServer::ServantBase_var
class.
<p>Similar reference counting related changes were made to the Timer Queues