[PyKDE] Which license applies to portable python scripts?

Gerard Vermeulen gvermeul at grenoble.cnrs.fr
Sun Apr 20 14:25:01 BST 2003

Sorry guys, I feel really unhappy about continuing, but I have to reply:

On Sat, 19 Apr 2003 20:54:28 +0100
Phil Thompson <phil at river-bank.demon.co.uk> wrote:

> > > So, while the code might be portable, the license may not be. Your users
> > > may only use your application in a "non-commercial setting". Your users
> > > may not use the GPL version of Qt (or PyQt) to run your application
> > > (because that contravenes the GPL).
> >
> > Phil, you made me feel a bad guy with respect to PyQwt-win-nc, but now I
> > think you are wrong on both points.
> >
> > (1) The second paragraph of term 0 of the GPL starts with:
> >
> >     Activities other than copying, distribution and modification are not
> >     covered by this License; they are outside its scope.  The act of
> >     running the Program is not restricted, and ...
> >
> >     So, it is perfectly legal to feed proprietary scripts into bash or
> >     proprietary programs into gcc. Why not the Python interpreter?
> Because, as far as Trolltech is concerned, the Python interpreter and PyQt are 
> irrelevant layers between your application and their software. Over the past 
> few years they have modified their licenses to include "(or a scripting 
> wrapper)" at various points as a way of making sure that PyQt doesn't provide 
> people with a way around their licenses. Therefore questions like this tend 
> to be easier to answer (because it's a more familiar question) if you imagine 
> your application is written in C++.
> The exact wording of the licenses may contain loopholes as far as the above 
> view is concerned. However, if anybody were to push/abuse it, then you can be 
> sure that the Qt licenses would be tightened up. In the worse case scenario 
> this would disallow "scripting wrappers" completely.
> Legal loopholes aside, I think the intent of what the Qt licenses are trying 
> to achieve is very clear and I fully support that intent.
My purpose was not to find loopholes in the Qt licenses, but to point out
a misinterpretation of the GPL: "(because that contravenes the GPL)".
IMHO, this phrase in this context is food for Microsoft's FUD machine.

The wording in the Qt non-commercial license is clear with respect to scripting
languages (I assume that it is also true for the commercial licenses) and I do
fully agree that one should not abuse those licenses.

However, Trolltech releases the Qt-X11-Free edition under the terms of the QPL
or the vanilla GPL. If Qt is to be used with a GPL'ed library, this implies
GPL, since QPL is incompatible with GPL.
And the GPL considers scripts as data, see:

With the best intents, I released PyQwt under the LGPL to make it clear that
it can be used by people with commercial licenses for Qt and PyQt (and Qt-NC).
After doing my homework, I realize that it is not allowed by the GPL --
-- and I wonder what to do.

Porting GPL'ed Qt programs to Windows is a breach of GPL and Trolltech harms
the free software community by endorsing it (if they do). The GPL is a license
like any other license and not just a thing that can be invoked when it is
convenient (even if one has to read the FAQ to understand it). It would be
much fairer, if Trolltech explicitly allowed LGPL'ed libraries developed with
a GPL'ed Qt.

Again, my apologies, but it is stronger than me,


PS: I won't pursue this, so anybody replying has the last word.

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