Hook - nsgomez/gzcom-dll GitHub Wiki
A hook is a class that implements cIGZFrameWorkHooks. When registered with the GZCOM Framework, a hook can be notified when the framework is performing major actions such as starting or shutting down the application.
In this sense, hooks are functionally equivalent to messages. The difference is that since the message server is itself a service, only a hook can receive information about the game state before the message server has started, or after it has shut down.
The return values of a hook method, such as PreAppInit, have no impact on the game or the instantiation of the class. For example, returning false in PreAppInit does not prevent the game from loading further, nor does it cause the game to unload your DLL.