Re: Heap problems after FreeLibrary

From:

"Igor Tandetnik" <itandetnik@mvps.org>

Newsgroups:

microsoft.public.vc.language

Date:

Tue, 16 May 2006 12:01:07 -0400

Message-ID:

<O#wsyHQeGHA.3888@TK2MSFTNGP04.phx.gbl>

Stefan <punkman@uboot.com> wrote:

I don't want to get into a design discussion, but actually I don't see
any problem with this approach (other than the fact that its
implementation is not working at the moment :). The plugin-DLL
performs some operation and has a well-defined interface which
returns an object known to the host library. Since the exact type of
the object returned might depend on the nature and/or result of the
operation performed, it makes sense that the plugin-DLL allocates
memory for that object from a shared memory pool (in this case the
CRT heap).

Ah, but you have two copies of the host library in your program, don't
you? So some resources are _not_ shared. In particular, you have two
copies of a vtable for each class.

I think you might save your approach by turning a "host library" itself
into a DLL, so you don't have two distinct copies floating around.
Otherwise, I don't quite see how it's going to work for anything but
trivial classes (those with no virtual functions).
--
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