ATL project with Win32 DLL exported functions

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

Anonymous - 29 Oct 2007 07:38 GMT

Is it possible to have an ATL project that also contains win32 exported
classes and functions?.

I have a project (module) that needs to export/expose a few ATL objects,
however, other modules depend on the existing exported C++ classes. I
have been adviced that to export the ATL COM object, I should do the ff:

1). Create an ATL project
2). Move the existing code to it

I would like to know if the new project can still export its
classes/functions, so that other dependent code can continue to work?

Reply to this Message

David Lowndes - 29 Oct 2007 08:47 GMT

>Is it possible to have an ATL project that also contains win32 exported
>classes and functions?.

If you're asking: can an ATL DLL expose exported functions as well as
its normal COM object(s), the answer is yes.

Dave

Reply to this Message

Ben Voigt [C++ MVP] - 29 Oct 2007 17:45 GMT

> Is it possible to have an ATL project that also contains win32 exported
> classes and functions?.
[quoted text clipped - 8 lines]
> I would like to know if the new project can still export its
> classes/functions, so that other dependent code can continue to work?

You can't export C++ classes (This isn't a restriction of ATL, but a general
issue that Windows has no universal ABI for C++ classes), but if you have
exported functions you can still do so.

Reply to this Message

Frank Hickman - 29 Oct 2007 18:37 GMT

>> Is it possible to have an ATL project that also contains win32 exported
>> classes and functions?.
[quoted text clipped - 12 lines]
> general issue that Windows has no universal ABI for C++ classes), but if
> you have exported functions you can still do so.

Yes C++ classes can be exported. Albeit not in the since that all
functionality is exposed but it is possible.

Signature

============
Frank Hickman
NobleSoft, Inc.
============
Replace the _nosp@m_ with @ to reply.

Reply to this Message

Ben Voigt [C++ MVP] - 29 Oct 2007 19:24 GMT

>>> Is it possible to have an ATL project that also contains win32 exported
>>> classes and functions?.
[quoted text clipped - 15 lines]
> Yes C++ classes can be exported. Albeit not in the since that all
> functionality is exposed but it is possible.

These things are safe for sharing C++ code:

Source code.
C-compatible exported functions, with a header with appropriate
declarations, and POD structs.
object v-tables, with either a header with pure interface declarations, IDL,
or a COM type library.

For the latter two you must respect memory ownership and always deallocate
in the same module which performed the allocation.

Anything else is highly compiler-specific, non-portable, and almost certain
to cause trouble with a compiler upgrade.

Reply to this Message

Rate this thread:

ATL project with Win32 DLL exported functions

Free Magazines