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Hello, I've written a fixed point decimal class in plain C++. I'd like to release this into the public domain. I'd also like to add some convenience functions for Qt (e.g., conversion to QString, etc). My question is that since I'm developing this with the open source version of Qt, does that mean that the version with Qt support is also GPLd/QPLd? (Meaning it cannot be used w/ the commercial version of Qt). Also, can I have the Qt code in the same file as the rest of the code (inside #ifdefs) along with a comment saying "if you define this, then this file is GPLd". Or do they need to be in separate files? Thanks! - Taj -- [ signature omitted ]
Hi, On Saturday 16 June 2007, Taj Morton wrote: > My question is that since I'm developing this with the open source > version of Qt, does that mean that the version with Qt support is also > GPLd/QPLd? (Meaning it cannot be used w/ the commercial version of > Qt). No, this means you have to release any code that binds to Qt under a GPL compatible license. You can find a list of compatible and incompatible licenses here: http://www.gnu.org/licenses/license-list.html#SoftwareLicenses If you chose one that allows linking with commercial software too, then it will likewise be permitted to use your code with commercial Qt. Konrad
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Message 3 in thread
On Sun, 2007-06-17 at 01:20 +0200, Konrad Rosenbaum wrote:
> Hi,
>
> On Saturday 16 June 2007, Taj Morton wrote:
> > My question is that since I'm developing this with the open source
> > version of Qt, does that mean that the version with Qt support is also
> > GPLd/QPLd? (Meaning it cannot be used w/ the commercial version of
> > Qt).
>
> No, this means you have to release any code that binds to Qt under a GPL
> compatible license. You can find a list of compatible and incompatible
> licenses here:
>
> http://www.gnu.org/licenses/license-list.html#SoftwareLicenses
>
> If you chose one that allows linking with commercial software too, then it
> will likewise be permitted to use your code with commercial Qt.
>
First I am puzzled as to why you say that source developed using Qt Open
Source Edition can be released under a GPL *compatible* licence. I
thought it had to be the GPL itself.
http://trolltech.com/products/qt/licenses/licensing/opensource
"If you wish to use the Qt Open Source Edition, you must contribute all
your source code to the open source community in accordance with the GPL
when your application is distributed."
True, that does say "application" not "library". I could be wrong about
the intent of "in accordance with", but in any event, no matter what
licence the OP chooses, the code cannot be used in a commercial Qt
product. It is not the GPL but rather Qt's commercial licence that
forbids this.
http://trolltech.com/products/qt/licenses/licensing/licensing
"The Commercial license does not allow the incorporation of code
developed with the Open Source Edition of Qt into a proprietary
product."
The OP's code has been developed in this way, so it may not be used in
products that are developed under a Qt commercial licence.
In any event, Trollech says, "If you are unsure about Trolltech's
licensing, we recommend that you contact sales."
Regards,
Stephen Jackson
--
[ signature omitted ]
Message 4 in thread
Hi,
Overdue disclaimer: IANAL
On Sunday 17 June 2007, Stephen Jackson wrote:
> On Sun, 2007-06-17 at 01:20 +0200, Konrad Rosenbaum wrote:
> > No, this means you have to release any code that binds to Qt under a
> > GPL compatible license. You can find a list of compatible and
> > incompatible licenses here:
> >
> > http://www.gnu.org/licenses/license-list.html#SoftwareLicenses
> >
> > If you chose one that allows linking with commercial software too, then
> > it will likewise be permitted to use your code with commercial Qt.
>
> First I am puzzled as to why you say that source developed using Qt Open
> Source Edition can be released under a GPL *compatible* licence. I
> thought it had to be the GPL itself.
>
> http://trolltech.com/products/qt/licenses/licensing/opensource
>
> "If you wish to use the Qt Open Source Edition, you must contribute all
> your source code to the open source community in accordance with the GPL
> when your application is distributed."
"In accordance with GPL" means "to comply with the terms of the GPL". The
GPL itself demands that you release your own code under a compatible
license if you link to GPL code - it does not explicitly say "make it GPL",
it says something along the lines of "no further restrictions" (so less
restrictions is fine).
KDE is under GPL and GPL compatible licenses (eg. all libraries allow
commercial linking).
> True, that does say "application" not "library". I could be wrong about
> the intent of "in accordance with", but in any event, no matter what
> licence the OP chooses, the code cannot be used in a commercial Qt
> product. It is not the GPL but rather Qt's commercial licence that
> forbids this.
>
> http://trolltech.com/products/qt/licenses/licensing/licensing
>
> "The Commercial license does not allow the incorporation of code
> developed with the Open Source Edition of Qt into a proprietary
> product."
This sounds a bit strange, since it is accepted practice to link commercial
Qt-apps to KDE-libs.
> The OP's code has been developed in this way, so it may not be used in
> products that are developed under a Qt commercial licence.
As long as the OP does not use Qt/commercial himself he is not bound by it.
And as I said it is accepted practice to link to KDE-libs.
Now what happens if he himself wants to use this code commercially - I don't
know.
> In any event, Trollech says, "If you are unsure about Trolltech's
> licensing, we recommend that you contact sales."
Good idea.
Konrad
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Message 5 in thread
On Sun, 2007-06-17 at 11:52 +0200, Konrad Rosenbaum wrote:
> Hi,
>
> Overdue disclaimer: IANAL
>
And neither am I.
> >
> > http://trolltech.com/products/qt/licenses/licensing/licensing
> >
> > "The Commercial license does not allow the incorporation of code
> > developed with the Open Source Edition of Qt into a proprietary
> > product."
>
> This sounds a bit strange, since it is accepted practice to link commercial
> Qt-apps to KDE-libs.
A bit strange it may be, but Trolltech's website has proclaimed this for
a long time.
>
> > The OP's code has been developed in this way, so it may not be used in
> > products that are developed under a Qt commercial licence.
>
> As long as the OP does not use Qt/commercial himself he is not bound by it.
> And as I said it is accepted practice to link to KDE-libs.
>
Hmm... well perhaps the perception is that this does not incorporate the
KDE-libs into the product. I don't think the same applies in relation to
the OP's point.
Sure the OP isn't bound by Qt's commercial licence, but he was asking
whether his code could be used by those who are. "My question is that
since I'm developing this with the open source version of Qt, does that
mean that the version with Qt support is also GPLd/QPLd? (Meaning it
cannot be used w/ the commercial version of Qt)."
And my point is that the quotation which you find "a bit strange" means
that his code cannot be used with the commercial version of Qt.
Regards,
Stephen Jackson
--
[ signature omitted ]
Message 6 in thread
On 17.06.07 13:21:57, Stephen Jackson wrote:
> On Sun, 2007-06-17 at 11:52 +0200, Konrad Rosenbaum wrote:
> > Hi,
> >
> > Overdue disclaimer: IANAL
>
> And neither am I.
Me neither.
> > > http://trolltech.com/products/qt/licenses/licensing/licensing
> > >
> > > "The Commercial license does not allow the incorporation of code
> > > developed with the Open Source Edition of Qt into a proprietary
> > > product."
> >
> > This sounds a bit strange, since it is accepted practice to link commercial
> > Qt-apps to KDE-libs.
>
> A bit strange it may be, but Trolltech's website has proclaimed this for
> a long time.
But it doesn't say what "incorporation of code" means, in particular I
think that doesn't include linking to open source code. Else kdelibs
wouldn't need to be lgpl'ed because nobody could use it in a commercial
application.
> > > The OP's code has been developed in this way, so it may not be used in
> > > products that are developed under a Qt commercial licence.
> >
> > As long as the OP does not use Qt/commercial himself he is not bound by it.
> > And as I said it is accepted practice to link to KDE-libs.
>
> Hmm... well perhaps the perception is that this does not incorporate the
> KDE-libs into the product. I don't think the same applies in relation to
> the OP's point.
Right.
> Sure the OP isn't bound by Qt's commercial licence, but he was asking
> whether his code could be used by those who are. "My question is that
> since I'm developing this with the open source version of Qt, does that
> mean that the version with Qt support is also GPLd/QPLd? (Meaning it
> cannot be used w/ the commercial version of Qt)."
>
> And my point is that the quotation which you find "a bit strange" means
> that his code cannot be used with the commercial version of Qt.
That depends, if the OP provides his code as a shared library which can
be linked into an application he can choose a library like lgpl or other
GPL compatible licenses that allow commercial apps linking. IMHO. If of
course the OP provides only the class in source format then this its
indeed not possible to use it in a commercial application.
Andreas
--
[ signature omitted ]
Message 7 in thread
Thank you everyone for all the replies!
On 6/17/07, Andreas Pakulat <apaku@xxxxxx> wrote:
> > And my point is that the quotation which you find "a bit strange" means
> > that his code cannot be used with the commercial version of Qt.
>
> That depends, if the OP provides his code as a shared library which can
> be linked into an application he can choose a library like lgpl or other
> GPL compatible licenses that allow commercial apps linking. IMHO. If of
> course the OP provides only the class in source format then this its
> indeed not possible to use it in a commercial application.
Yes, I was planning on offering i in class/source form (it's not that
huge, and a shared lib seems overkill).
My other question was regarding how tightly I could integrate Qt
support (with the Qt version licensed under something compatible with
GPL). Could I have the Qt stuff inside the (public domain) file, just
hidden inside #ifdefs? Or, do I need to create 2 files, one with Qt
support (GPLdish), and one without (public domain)?
Thanks again,
- Taj
--
[ signature omitted ]
Message 8 in thread
On 17.06.07 08:30:00, Taj Morton wrote:
> Thank you everyone for all the replies!
>
> On 6/17/07, Andreas Pakulat <apaku@xxxxxx> wrote:
> >> And my point is that the quotation which you find "a bit strange" means
> >> that his code cannot be used with the commercial version of Qt.
> >
> >That depends, if the OP provides his code as a shared library which can
> >be linked into an application he can choose a library like lgpl or other
> >GPL compatible licenses that allow commercial apps linking. IMHO. If of
> >course the OP provides only the class in source format then this its
> >indeed not possible to use it in a commercial application.
> Yes, I was planning on offering i in class/source form (it's not that
> huge, and a shared lib seems overkill).
>
> My other question was regarding how tightly I could integrate Qt
> support (with the Qt version licensed under something compatible with
> GPL). Could I have the Qt stuff inside the (public domain) file, just
> hidden inside #ifdefs? Or, do I need to create 2 files, one with Qt
> support (GPLdish), and one without (public domain)?
You have to provide two classes/files, one with one without Qt support.
Andreas
--
[ signature omitted ]
Message 9 in thread
Hi,
> True, that does say "application" not "library". I could be wrong about
> the intent of "in accordance with", but in any event, no matter what
> licence the OP chooses, the code cannot be used in a commercial Qt
> product. It is not the GPL but rather Qt's commercial licence that
> forbids this.
I understand "in accordance with" means "compatible with", so it should be
possible to write code that can be used both by GPL and commercial products.
KDE, for example, is licensed under LGPL which is compatible with GPL.
Lesser BSD is also an option as it is compatible with both the GPL and
proprietary development.
Of course this is not legal counseling - just a personal opinion.
--
[ signature omitted ]
Message 10 in thread
On Sunday 17 June 2007, Dimitri wrote:
> KDE, for example, is licensed under LGPL which is compatible with GPL.
Actually: most KDE apps are under GPL, most libraries under LGPL, but there
are other licenses too: MIT, X11, etc.pp. All of them GPL compatible, all
libraries also commercially linkable.
Konrad
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Message 11 in thread
On Sun, 2007-06-17 at 10:35 +0200, Dimitri wrote:
> Hi,
>
> > True, that does say "application" not "library". I could be wrong about
> > the intent of "in accordance with", but in any event, no matter what
> > licence the OP chooses, the code cannot be used in a commercial Qt
> > product. It is not the GPL but rather Qt's commercial licence that
> > forbids this.
>
> I understand "in accordance with" means "compatible with", so it should be
> possible to write code that can be used both by GPL and commercial products.
>
I accept that this is a possible interpretation of "in accordance with"
- though not one that I would personally rely on. However, in order to
write code that "can be used both by GPL and commercial products" the OP
would have needed a commercial licence before he started. (It's a pity
that it doesn't say "compatible with"; this is a term that is familiar
in this context.)
I have a Qt commercial licence. As far as I understand it, no matter how
the OP publishes his code, I cannot use it in a commercial application
because the Qt commercial licence "does not allow the incorporation of
code developed with the Open Source Edition of Qt into a proprietary
product", as I already quoted.
Dimitri, are you saying the the OP *can* publish his code which was
developed with the Qt Open Source Edition and that such code can be used
by Qt commercial users?
Regards,
Stephen Jackson
--
[ signature omitted ]
Message 12 in thread
Warning: I am not a lawyer! However, I do not need to dispense legal advice
here because there's already a source for this kind of information:
http://trolltech.com/developer/faqs/Licensing
Stephen Jackson wrote:
> I have a Qt commercial licence. As far as I understand it, no matter how
> the OP publishes his code, I cannot use it in a commercial application
> because the Qt commercial licence "does not allow the incorporation of
> code developed with the Open Source Edition of Qt into a proprietary
> product", as I already quoted.
The situation this aims to avoid is the one described here:
"Can we use the Open Source Edition while developing our non-opensource
application and then purchase commercial licenses when we start to sell
it?"
[http://trolltech.com/developer/knowledgebase/182/]
> Dimitri, are you saying the the OP *can* publish his code which was
> developed with the Qt Open Source Edition and that such code can be used
> by Qt commercial users?
Commercial users can use code licensed under certain liberal licenses with
the Commercial Edition as long as those licenses are compatible with it.
However, they can't mix GPL-licensed code in a product that uses the
Commercial Edition because those licenses are incompatible.
Of course, this is a completely different situation to the one where the
original poster wants to dual license his code in the same way as Qt:
"I want to dual license my software too! That means I can use the Open
Source edition for development, right?"
[http://trolltech.com/developer/knowledgebase/123/]
--
[ signature omitted ]