Re: GPL and Plug-INs and XML\Ada

[Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>]

"David Botton" <David@Botton.com> writes:

> If a person wrote an executable that had a plug-in architecture, would it be
> possible then to include GPL'd plug-ins with out the application becoming
> GPL'd?
> 
> For example, If I wrote an application that had a closed lic. and it allowed
> features to be plugged-in. One such group of features was for file "import".
> So, I throw together a GPL'd plug-in that included XML\Ada and dropped that
> dll in the dir and it is picked up at run time by the closed lic.
> application.

The key is the linking mechanism. I asked essentially the same
question on a Windows CVS mailing list; apparently the Free Software
Foundation position is that a "dll" (which stands for Dynamic Link
Library) is _linked_, which is the term used in the GPL. So GPL dlls
do "infect" the full app.

> This would be different than:
> 
> I write an XML COM object that uses XML\Ada and now my XML COM object is of
> course GPL'd, but closed lic. programs (say in VB or Ada) could now use my
> XML COM object to access XML.

Here, since the connection between the application program and the COM
object is by message passing over a network (hmm, I'm just assuming
that), there is no "linking" in the GPL sense. So I would say no, the
application is not infected by the COM object's GPL.

> I could see where this case would be problematic (although I
> question that also), but the previous cases seems to be no problem.
> Would including a GPL'd COM / Corba object virus to my app and make
> it GPL'd?
> 
> Thoughts?

Obviously we came to different conclusions from the same data.
Clearly, if you are seriously considering marketing either of these
mechanisms, get the advice of a competent lawyer!

-- 
-- Stephe