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Hi, By using the Open Source version of QT in my project I must also GPL my program meaning that I must attached full program source when I redist. So, how come KDELibs is not GPL but LGPL? I mean, isn't KDELibs built upon the QT framework? What am I missing here? Regards, Martin -- [ signature omitted ]
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi Martin, May be are some issues in GPL licensing aren't clear to you. If you have some lib GPL-Licensed, you can create another lib that's are linked with the GPL lib and choose a GPL compatible license to your lib. Then, you can write libs based on Qt and choose an BSD ( most recent version ), LGPL and other compatible license. That's are valid for an application too. I'm not a lawyer, but that's I think about this issue. And, if a guy needs to develop an commercial app using KDE libs, ok, but this guy needs a commercial Qt license. Regards, Wagner Martin Olsson wrote: > Hi, > > By using the Open Source version of QT in my project I must also GPL > my program meaning that I must attached full program source when I > redist. > > So, how come KDELibs is not GPL but LGPL? I mean, isn't KDELibs > built upon the QT framework? What am I missing here? > > > > Regards, > Martin > > -- > To unsubscribe - send a mail to qt-interest-request@xxxxxxxxxxxxx > with "unsubscribe" in the subject or the body. > List archive and information: http://lists.trolltech.com/qt-interest/ > > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFFv4vcG0tpd3N7UOYRAuEbAJ9r26zFIXdSx8dxvMYXzinvCGYQBQCdFDD7 +JE3p1QzHhzFZEMTA1uSe4Q= =Y7Ir -----END PGP SIGNATURE----- _______________________________________________________ Yahoo! Mail - Sempre a melhor opção para você! Experimente já e veja as novidades. http://br.yahoo.com/mailbeta/tudonovo/ -- [ signature omitted ]
Martin Olsson wrote: > > By using the Open Source version of QT in my project I must also GPL my > program meaning that I must attached full program source when I redist. No, you've misunderstood. TT did not say that you have to release your program under the GPL. TT says that *if* you distribute your program, you must do it under a GPL-compatible license. (See http://www.trolltech.com/developer/knowledgebase/187/) A list of GPL-compatible licenses (and what that means) can be found here: http://www.gnu.org/philosophy/license-list.html#GPLCompatibleLicenses > So, how come KDELibs is not GPL but LGPL? I mean, isn't KDELibs built > upon the QT framework? What am I missing here? Qt is not embedded into KDE. KDE did not repackage Qt under a new license. KDE is an application that utilizes the Qt library (KDE libs links to the Qt libs). Since the FSF says that LGPL and GPL are compatible licenses, that means that you can distribute them together and link the programs together. Linking an LGPL program to a GPL program like this is OK according to the licenses, to the FSF, and to Trolltech. -Gabriel -- [ signature omitted ]
Gabriel M. Beddingfield wrote: > Qt is not embedded into KDE. KDE did not repackage Qt under a new > license. KDE is an application that utilizes the Qt library (KDE libs > links to the Qt libs). Since the FSF says that LGPL and GPL are > compatible licenses, that means that you can distribute them together > and link the programs together. Linking an LGPL program to a GPL > program like this is OK according to the licenses, to the FSF, and to > Trolltech. But then, if one uses the resulting library, which license can be used GPL, LGPL, both ? Consider this case: I take a cool GPL lib, I add some extra code around it in order to create a new lib, that I release under the LGPL. Then I use my modified lib as a black box in my commercial application. Seems to break the GPL principles right ? -- [ signature omitted ]
On Wednesday 31 January 2007 10:49:15 Gilles Debunne wrote: > Gabriel M. Beddingfield wrote: > > Qt is not embedded into KDE. KDE did not repackage Qt under a new > > license. KDE is an application that utilizes the Qt library (KDE libs > > links to the Qt libs). Since the FSF says that LGPL and GPL are > > compatible licenses, that means that you can distribute them together > > and link the programs together. Linking an LGPL program to a GPL > > program like this is OK according to the licenses, to the FSF, and to > > Trolltech. > > But then, if one uses the resulting library, which license can be used GPL, > LGPL, both ? > > Consider this case: I take a cool GPL lib, I add some extra code around it > in order to create a new lib, that I release under the LGPL. Then I use my > modified lib as a black box in my commercial application. Seems to break > the GPL principles right ? You cannot take a GPL library, add extra code and release the code under a new license (LGPL) without having the rights to relicense the original GPL code. There is obviously a difference between relicensing code and license compatibility. In your example it is perfectly fine to redistribute the library that contains GPL and LGPL code because the two licenses are compatible, but it means that you're distributing it under the terms of /both/ licenses, not just one. It is not dual licensing where you can choose, you have to comply with all used licenses. Simon
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Message 6 in thread
On 31.01.07 10:49:15, Gilles Debunne wrote:
> Gabriel M. Beddingfield wrote:
>
> >Qt is not embedded into KDE. KDE did not repackage Qt under a new license. KDE is an
> >application that utilizes the Qt library (KDE libs links to the Qt libs). Since the FSF says
> >that LGPL and GPL are compatible licenses, that means that you can distribute them together and
> >link the programs together. Linking an LGPL program to a GPL program like this is OK according
> >to the licenses, to the FSF, and to Trolltech.
>
> But then, if one uses the resulting library, which license can be used GPL, LGPL, both ?
>
> Consider this case: I take a cool GPL lib, I add some extra code around it in order to create a
> new lib, that I release under the LGPL. Then I use my modified lib as a black box in my
> commercial application. Seems to break the GPL principles right ?
Right that doesn't work. However you miss the point that one is
perfeclty able to buy a commercial licnse for Qt and then link lgpl
KDElibs against that and then build a commercial app on top of both.
The important thing here is that Qt is both GPL and commercial (and
there are differences between both versions).
Andreas
--
[ signature omitted ]
Message 7 in thread
Andreas Pakulat wrote:
> On 31.01.07 10:49:15, Gilles Debunne wrote:
>
>> Gabriel M. Beddingfield wrote:
>>
>>
>>> Qt is not embedded into KDE. KDE did not repackage Qt under a new license. KDE is an
>>> application that utilizes the Qt library (KDE libs links to the Qt libs). Since the FSF says
>>> that LGPL and GPL are compatible licenses, that means that you can distribute them together and
>>> link the programs together. Linking an LGPL program to a GPL program like this is OK according
>>> to the licenses, to the FSF, and to Trolltech.
>>>
>> But then, if one uses the resulting library, which license can be used GPL, LGPL, both ?
>>
>> Consider this case: I take a cool GPL lib, I add some extra code around it in order to create a
>> new lib, that I release under the LGPL. Then I use my modified lib as a black box in my
>> commercial application. Seems to break the GPL principles right ?
>>
>
> Right that doesn't work. However you miss the point that one is
> perfeclty able to buy a commercial licnse for Qt and then link lgpl
> KDElibs against that and then build a commercial app on top of both.
>
> The important thing here is that Qt is both GPL and commercial (and
> there are differences between both versions).
>
> Andreas
>
>
Is that to say that if you make a commercial closed sourced application
that runs on KDE with KDELibs then you have to buy a QT commercial license?
Is it a GPL loop hole?
--
[ signature omitted ]
Message 8 in thread
Karl Hiramoto wrote:
> Andreas Pakulat wrote:
>> On 31.01.07 10:49:15, Gilles Debunne wrote:
>>
>>> Gabriel M. Beddingfield wrote:
>>>
>>>
>>>> Qt is not embedded into KDE. KDE did not repackage Qt under a new
>>>> license. KDE is an application that utilizes the Qt library (KDE
>>>> libs links to the Qt libs). Since the FSF says that LGPL and GPL
>>>> are compatible licenses, that means that you can distribute them
>>>> together and link the programs together. Linking an LGPL program
>>>> to a GPL program like this is OK according to the licenses, to the
>>>> FSF, and to Trolltech.
>>>>
>>> But then, if one uses the resulting library, which license can be
>>> used GPL, LGPL, both ?
>>>
>>> Consider this case: I take a cool GPL lib, I add some extra code
>>> around it in order to create a new lib, that I release under the
>>> LGPL. Then I use my modified lib as a black box in my commercial
>>> application. Seems to break the GPL principles right ?
>>>
>>
>> Right that doesn't work. However you miss the point that one is
>> perfeclty able to buy a commercial licnse for Qt and then link lgpl
>> KDElibs against that and then build a commercial app on top of both.
>>
>> The important thing here is that Qt is both GPL and commercial (and
>> there are differences between both versions).
>>
>> Andreas
>>
>>
>
> Is that to say that if you make a commercial closed sourced
> application that runs on KDE with KDELibs then you have to buy a QT
> commercial license?
> Is it a GPL loop hole?
>
It is not a loop hole. After googling i see:
http://kdemyths.urbanlizard.com/myth/59
http://developer.kde.org/documentation/books/kde-2.0-development/ch19.html
**Myth
You can't write closed source KDE applications because, while the KDE
libraries are LGPLed, Qt is under the GPL.
**Facts
You can write closed source applications for KDE, if you aquire a Qt
license from Trolltech to do so.
While the GPL requires that all program that link against GPL'd code
also be GPL'd, the LGPL makes no such restrictions.
Therefore, the KDE libraries (which are LGPLed) do not restrict the
licensing of code they are linked against. The limiting factor becomes
Qt itself (commercial, GPL or QPL).
If you develop using a commercially licensed Qt, you can distribute your
KDE program under a commercial license of your choice.
If you develop using Qt Free Edition, your program must also be Free (it
must be released under a license that is compatible with either the GPL
or the QPLv2).
--
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