Re: Allow DLLs to access a Singleton
"Ben Pope" <benpope81_REMOVE_@gmail.com> wrote in message
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"Igor Tandetnik" <itandetnik@mvps.org> wrote in message
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"Ben Pope" <benpope81_REMOVE_@gmail.com> wrote in message
news:44b2caa1$0$16692$88260bb3@news-taz.teranews.com
Currently I have a main application that loads DLLs. The main
application has a factory, that is a singleton. How do I allow the
DLLs to access that singleton?
Define an interface - an abstact C++ class with no data members and
all functions pure virtual. Have your singleton class implement this
interface (derive from it and implement its methods). Have every DLL
export a SetSingleton function that takes a pointer to this
interface. Call this function right after loading each DLL.
I'm not sure I follow. The singleton cannot be instantiated, and thus
cannot be passed by pointer.
What do you mean? What's to stop your main app from doing something like
Init(&Singleton<MyClass>::Instance());
where Init() is implemented in the DLL?
--
With best wishes,
Igor Tandetnik
With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925
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