ready to use python, need help with GUI decision

David MacQuigg dmq at
Sun Mar 7 01:54:45 CET 2004

On 07 Mar 2004 00:05:38 +0200, Ville Vainio <ville at>

>>>>>> "David" == David MacQuigg <dmq at> writes:
>    David> On Wed, 3 Mar 2004 18:15:44 +0000, Jonathon McKitrick
>    David> <jcm at> wrote:
>    David> I believe the licensing issue with Qt is overblown.  If
>    David> your work is purely non-commercial, use the GPL license.
>    David> If you are a typical commercial developer, it should be no
>    David> problem to pay $1550 per developer license (no runtime
>    David> royalties).  I've heard there are problems for commercial
>    David> developers who can't afford the $1550.  I would say, don't
>    David> worry.  If your project fails to make a profit, I really
>    David> doubt Trolltech is going to sue you.  I think they would be
>    David> quite happy to get the first $1550 of any successful
>    David> project.
>So you urge people to break copyright law until they can afford to pay
>the license? I would expect such a behaviour to prove extremely
>problematic and dangerous.

I'm not urging anyone to break the law, not even those few commercial
developers who can't afford the the license.  What I'm saying is that
if you are in this rare situation, can't afford the licesne, and not
sure your product will ever be sold, you just have to be careful not
to release the product before paying your dues.  The only "danger" I
can see is that code developed before you have paid for the commercial
license could get loose and allow someone to claim it as GPL and avoid
paying your license.  Maybe I'm misunderstanding the problems and
dangers you forsee.  Could you be more specific?

>I would suggest instead that all the "valuable", back end parts of a
>program be coded UI-independently (good idea in any case), and then
>finally GUI is tacked on by connecting it to the back end via CORBA
>(or equivalent). That way the GUI (which is worthless w/o the back
>end) can be GPL'd.

This seems to me a deliberate thwarting of Trolltech's intentions.  It
may be legal, but to me it seems like taking advantage of their
generosity in offering a GPL license at all.  I also question the
legality.  It gets down to a question of whether "connecting via
CORBA" is equivalent to "linking".  There is certainly more danger in
that than anything I am suggesting.  There is also danger on the GPL
end.  It seems like what you are suggesting is no different than
releasing a program under GPL, but with-holding a key piece for which
you charge a license.

>OTOH, I would probably just use GTK or wxPython. In fact, I wouldn't
>even bother learning Qt - GPL or a crapload of Euros probably won't be
>terms an average employer would approve (esp. if you have to use
>Windows at work), so Qt would be restricted to home use alone.

Once it is clear your project will go commercial, just pay the license
and avoid the worries.  Surly $1550 is no big deal at that point.  I
have never understood the intensity of this debate over the Qt
licenses.  I guess I never will.

-- Dave

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