Re: proposed FAQ entries about licensing

[Jaroslav Hajek]

On Wed, Apr 8, 2009 at 7:30 PM, David Bateman <address@hidden> wrote:
> Jaroslav Hajek wrote:
>>
>> Wikipedia says the dispute whether dynamic linking constitutes a
>> derivative work is not legally clear
>> (http://en.wikipedia.org/wiki/GPL#The_GPL_in_court) but it seems FSF's
>> opinion is clear - it does, and a GPL library needs to provide a
>> linking exception to allow the dynamic linking.
>> Of course, disclaiming that the linking constitutes a derivative work
>> would be probably equivalent, but I think it must be stated by the
>> license, not a FAQ list, and must be thus agreed upon by copyright
>> holders.
>> Given that the there is neither a linking exception nor a disclaimer
>> statement in any of Octave's sources, my opinion is that compiled mex
>> files linked against Octave libraries are covered by GPL, at least
>> potentially (if FSF is right).
>>
>
> This is not a case of dynamic linking as in the case given in the wikipedia
> article. The case is of a API to a plugin interface that is not GPLed  (ie
> the MEX interface). John specifically asked the FSF legal people about
> exactly this issue and they considered that it was ok to distribute binary
> mex files as long as they are not distributed in a manner that makes them
> and Octave a single product. I'll let John confirm the exact text as it was
> John that was the interface with the FSF on this question..
>
> D.

OK, I believe you, but I just don't understand the reasoning, then.
There is also the (albeit slight) possibility that the FSF people
missed some important detail. I see the link to liboctave et al.
hard-wired in the produced mex file and that seems to me to make it a
derivative work of Octave. There's certainly no liboctave in Matlab,
so it's apparent the executable is built to be linked to Octave.
Maybe I don't understand the part "plugin interface that is not
GPLed".  Is there any part of Octave's sources not covered by GPL?
I think mex.h carries the GPL preamble, doesn't it?


-- 
RNDr. Jaroslav Hajek
computing expert & GNU Octave developer
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz