Win32s OLE 16/32 Interoperability
PSS ID Number: 123422
Article Last Modified on 1/19/2000
The information in this article applies to:
This article was previously published under Q123422
SUMMARY
The OLE support provided in Win32s version 1.2 provides full 16/32
interoperabililty for local servers (EXE servers). Therefore, you can
embed a 32-bit object implemented by a local server in a 16-bit container
and vice-versa.
There is no built-in support in Win32s for 16/32 interoperability for
in-process servers (DLL servers). However, you can use Universal Thunks
to load a 16-bit DLL in the context of a 32-bit process. This allows you
to embed a 16-bit object implemented by a DLL server in a 32-bit
container. However, it is quite complicated to write this code because:
- Any OLE interface has a hidden "this" pointer which you must handle in
your thunking code.
- OLE uses callbacks. If your 32-bit container calls IDataObject:DAdvise,
then your 16-bit server may call back into the 32-bit side with the
Advise interface. Your thunking code will have to handle this type of
conversation.
NOTE: Embedding a 32-bit object implemented by an in-process server in a
16-bit container is supported under Windows NT 3.5. However, this
functionality may not work correctly for your in-process server because
IDispatch and any custom interfaces do not work.
Keywords: KB123422
Technology: kbWin32s120 kbWin32sSearch