Re: [Firebird-devel] Reference counters in API - was Re: Providers, yvalve, external engines and object lifecycle

[Kovalenko D. <dmi...@gm...>]

>   Ok, here is a code:
>
> Interface* a = new RefCountedClass;
> Interface* b = NULL;
> b = a;
> delete a;
> b->Anything();
>
>   I don't understand how reference counting works here. Could you explain?

InterfacePtr a(new RefCountedClass()); //cntRef==1
InterfacePtr b;

a=b; //cntRef==2

a.Release(); //or a=NULL; //cntRef==1

b->Anything();

b.Release(); //last release
b.Release(); //no problem

---
When you work with RefCountedClass, you must forget about "operator delete"

In good C++ code, you do not make a explicit call of AddRef/Release. This is 
work for smart-pointer

Regards,
Kovalenko Dmitry