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List:       kde-licensing
Subject:    Re: [rms@gnu.org: Re: can normal programs be LGPL'ed?]
From:       "Adam J. Richter" <adam () yggdrasil ! com>
Date:       1998-12-12 8:39:27
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Odd number of ">" = Kevin Forge
Even number of ">" = Adam Richter

>> >> QPL-0.91 does not grant the right to distribute modifications in a format
>> >> other than original source + patch, and QPL-0.91 does not grant the right
>> >> to integrate modifications that Troll Tech does not at least have
>> >> ability to allow its customers to link into proprietary derivative
>> >> works.
>> >
>> >OK..  So we can't link against LGPL code then.  After all, Mods to an
>> >LPL
>> >app must be under the LPL and that means granting the right to link
>> >against
>> >Proprietary apps.
>> 
>>         No.  That is the basically difference between the GPL and the
>> LGPL.  You can link an LGPL'ed library against more restricted code
>> provided that you meet certain other requirements (basically, you
>> have to distribute source to the LGPL'ed part

>No you just have to provide "access to the source or a promise of such".
>The QT Runtime is QPL Licensed too so you can always get the source.

	First let me clarify something, because I did gloss over an
aspect of the LGPL above.  If you modify an LGPL'ed library in certain
ways, you do have make source for that available, but if you only link
against it, you do not have to make available the source to the part
that is only being linked, provided that you meet certain other
requirements (basically, you have to distribute source to the LGPL'ed
part).  For the GPL, there is no such distinction.  You have to make
full source available if you distribute the derivative work.

	Now, to get to your main point, you are correct in that LGPL
and QPL are similar in that Troll Tech does have the right to link
proprietary programs with libraries covered by either set of copying
conditions (provided that they meet various other restrictions).
However, it is incorrect to say that modifications to any LGPL library
must grant the right to right to link against proprietary software.
You can produce a derivative work that is covered by the GPL rather
than the LGPL, per section 10 of the LGPL.

>> and provide the program
>> in a form where a modified version of the LGPL'ed library could be
>> linked in).

>If it isn't in such a form then it's not using the LGPLed code.

	That is incorrect.  For example, it is illegal to distribute a
statically linked work consisting of a program and LGPL'ed library
without also distributing the proprietary program in unlinked form
(i.e., the .o files, or as one big .o file without the library linked
in).  That is an example of an illegal way to use LGPL'ed code.


>Can I make a Patch to a GPLed Library and put my patch under a different
>license ?  Quick answer "no".  This means that the right to link it to
>proprietary code stands.  

	I don't follow you here.  The GPL gives you no right to link a
GPL'ed library with proprietary code in the first place.  If you meant
an *LGPL'ed* library, then the answer is that you could deny people
the right to link proprietary apps by distributing mods under GPL,
turning the library a GPL'ed library, by exercising section of the LGPL.


>My contention is that QPL is a compromise between the GPL and the LGPL.

	If you are claiming that the restrictions of the QPL are a
subset of the GPL's and a superset of the LGPL's, that is not true.
The two examples that I gave (the right to distribute modifications
that Troll Tech does not have the right to grant permission for
linking into proprietary apps, and the right to distribute
integrated source code to a modified version).


>What would you have Troll Tech do that doesn't bankrupt the company ?

	I am trying to help you understand the GNU copying conditions.
I don't know if I want to have a speculative discussion about business
strategies, but I will give you a quick summary without getting into
detail.  There are a plethora of choices, but the one closest to
Troll's present philosophies would probably be to GPL libQt and sell
the right to link proprietary apps, requiring contributors to grant
Troll's customers the additional right link proprietary apps if they
want their modifications included included in the "official" releases.
(In general, free software projects only fork when maintenance is
slow, and forking is not the end of the world.)


>> >As for the patch clause.  HTTP://www.troll.no/qpl
>> >It's gone :).
>> 
>>         No.  The restriction has only been loosened slightly.  You still
>> can only distribute modifications "in a form distinct from the Software."

>Yes.  Which means that you can't claim your patched version is the true
>QT from Troll Tech.  Basicaly they have legislated against fraud. :)

	The QPL restriction on source distribution are beyond the
requirements of attribution, but the important thing to understand
with respect to the GPL is that this restriction, whatever you may
think of its justification, constitutes an additional restriction
beyond that of the GPL.

Adam J. Richter     __     ______________   4880 Stevens Creek Blvd, Suite 104
adam@yggdrasil.com     \ /                  San Jose, California 95129-1034
+1 408 261-6630         | g g d r a s i l   United States of America
fax +1 408 261-6631      "Free Software For The Rest Of Us."

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