Re: singleton in a DLL loaded class

From:
"Igor Tandetnik" <itandetnik@mvps.org>
Newsgroups:
microsoft.public.vc.language
Date:
Mon, 25 Jun 2007 14:29:18 -0400
Message-ID:
<utmK$a1tHHA.4424@TK2MSFTNGP04.phx.gbl>
PaulH <paul.heil@gmail.com> wrote:

I have a class loaded from a DLL that I would like to implement as a
multi-threadable singleton. Unfortunately, I seem to still be getting
two distinct instances of this class. It is implemented as below.

//singletonclass.h
class SingletonClass : BaseClass
{
public:
   static SingletonClass& Instance();
   ~SingletonClass();
   //... Implement BaseClass functions
private:
   static std::auto_ptr< SingletonClass > _theInstance;
   static Mutex* _m;
}

//singletonclass.cpp
std::auto_ptr< SingletonClass > SingletonClass::_theInstance;
Mutex* SingletonClass::_m;

/*static*/ SingletonClass& SingletonClass::Instance()
{
   Mutex::Create( &_m );


What does Mutex::Create do? It appears you are creating a new mutex
every time Instance() is called.
--
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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