Hi Ion.
Although so far only two people consider this library interesting.
Actually I'd be most interested in such a library. I at the moment use my own solution for the same problem. I ran into the same trouble you describe in your documentation but did not get a chance to dig in so deep as I had a real-world problem to solve in a real-world time frame :-))). I did create a SharedMemory object which works, together with my SharedMemoryId objects which are actually offset based pointers that can be stored inside the SharedMemory area. (Can't tell you how much I hate it when I get sloppy and store a standard C++ reference in there only to find it is not usable from another process. :-))) My SharedMemoryId objects (actually called RepositoryId and WriteableRepositoryId as the my model is pretty domain specific) use an offset from the start of their SharedMemory area and when you use them you need to specify which SharedMemory object they relate to. I like your design with an offset from their own address much better as that would allow my * and -> operators to not rely on one global SharedMemory object (which was enough in my case). And I guess having a larger generic ptr that can be 0, and a smaller non-null one is a small-enough price to pay (much better than my relying on a global shared memory object when using standard C++ dereferencing operators). I did not implement any smart memory allocation schemes as my shared memory space was only allocated and never needed to be deallocated. I use a placement new operator (as in 'new (someSharedMemoryArea) int(5)') which just stores the object on the next available location in the shared memory area, and the memory allocation information is not shared so only one user allocates the memory after which it allows read-only access only. Unfortunately this also prevents me from directly using any 'smarter' data structures there, like strings or vectors, that sometimes need to reallocate their storage space. As for the standard C++ library containers - I tried the allocator approach and ran into the same allocator problems you encountered. In the end I just needed a list structure so I rolled out my own and made it an STL compatible container so that it can be used with standard C++ library algorithms. Hope you see you're not alone out there... like I thought I was when I did this... :-). If you need any help please just holler... I'll see what I can do... When I get the time I'll try to use your library in my project so you'll have another real-world test user application available (Windows/MS Visual Studio .NET 2003, and will be ported over to *nix/gcc some time next year - so if the library is portable its a major bonus as otherwise I'd have to rewrite my own). Many thanks for all the effort you put in this so far. Certainly looks promising. Best regards, Jurko Gospodnetic