Re: [boost] [interprocess] sharing memory between 32 bit and 64 bit Windows processes

Subject: Re: [boost] [interprocess] sharing memory between 32 bit and 64 bit Windows processes
From: Arno Schödl (aschoedl_at_[hidden])
Date: 2011-02-09 03:30:19

> > I think we have a possible solution: Making size_t/ptrdiff_t always
> > 64 bit makes the same offset_ptr work fine in both environments, and
> > solves similar problems in rb_tree_best_fit as well. We have a
> > prototype working.

> Nice to hear it.

> > Can we template the size_t/ptrdiff_t size into offset_ptr? For
> > example:
> >
> > template<class PointedType, class DifferenceType=ptrdiff_t>  class
> > offset_ptr;
> >
> > Then all other classes could derive their size_types and
> > difference_types from their pointer type as unsigned/signed
> > std::iterator_traits<pointer_type>::difference_type. Is that ok with
> > you?

> That could be reasonable, but I don't know how much code we'll need to 
> make dependent on the pointer type. Managed memories are already 
> dependent on the pointer type, so I guess there is not much impact. 
> Containers and other types will be harder, in these cases we'll need to 
> make the allocator's pointer type customizable so that the container 
> uses the corresponding size_type/difference_type.

> I'll add this to my to-do list, but I'm, afraid I have higher priority 
> issues right now in the library.

We'd implement it, as long as you are willing to review it and allow it into boost.

Regards,

Arno

--
Dr. Arno Schödl | aschoedl_at_[hidden]
Technical Director
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