[GRASS-dev] v.digit: Qt or wxWidgets

[Glynn Clements]

Ron Yorston wrote:

> > http://www.trolltech.com/products/qt/licenses/licensing
> > 
> > 	You must purchase a Qt Commercial License from Trolltech or
> > 	from any of its authorized resellers before you start
> > 	developing proprietary software. The Commercial license does
> > 	not allow the incorporation of code developed with the Open
> > 	Source Edition of Qt into a proprietary product.
> > 
> > http://www.trolltech.com/products/qt/licenses/licensing/opensource
> > 
> > 	Based on the "Quid Pro Quo" principle, if you wish to derive a
> > 	commercial advantage by not releasing your application under
> > 	an open source license, you must purchase an appropriate
> > 	number of commercial licenses from Trolltech. By purchasing
> > 	commercial licenses, you are no longer obliged to publish your
> > 	source code.
> > 
> > http://www.trolltech.com/developer/downloads/qt/faq
> > 
> > 	If you are working in a commercial environment and are
> > 	required to keep the source code of your product closed, you
> > 	must use the commercial version instead. Trolltech's
> > 	commercial license terms do not allow you to start developing
> > 	proprietary software using the Open Source edition.
> > 
> > http://www.trolltech.com/developer/downloads/qt/x11
> > 
> > 	If you are writing proprietary/commercial software, or if you
> > 	plan to commercialize the software you are writing with Qt,
> > 	you must use a commercial version of Qt. Please refer to the
> > 	Open Source Downloads info page for reasons why.
> > 
> > Now, all of these could be considered mistakes in wording, based upon
> > the assumption that the software will ultimately be distributed. Or
> > they could be the result of TrollTech misunderstanding the
> > consequences of releasing Qt under the GPL. Or they could be a
> > calculated attempt to sell more commercial licences by misleading
> > users as to the scope of the rights granted by the GPL.
> > 
> > If the only licence which is included in the official Qt Open Source
> > version distributed by TrollTech is a copy of the GPL, then there's no
> > problem. You have the rights stated there regardless of TrollTech's
> > interpretation of them.
> 
> I think TrollTech have a very clear understanding of the GPL and its
> consequences.
> 
> The items quoted from their website all say in different ways that
> 'you must' use a commercially licensed version of Qt if you want to
> distribute your software and keep the source code closed.

No they don't.

That may be what was intended, but it isn't what is actually said
above. All of those quotes omit the "distribute your software" part;
i.e. they say that you must use the commercial version if you want to
keep the source closed, with no mention of distribution.

Assuming that the above are due simply to a poor choice of wording[1],
they wouldn't be the first to make that mistake. Netscape made a
similar error with the original draft of the Mozilla Public Licence,
stating that "you must publish the modified version under the terms of
this licence", rather than "if you publish the modified version, you
must do so under the terms of this licence".

[1] If Qt's licencing terms really did require you to publish
"private" derivative works, I think that the FSF would have said
something by now.

-- 
Glynn Clements <glynn at gclements.plus.com>