Re: proposed FAQ entries about licensing

[Jaroslav Hajek]

On Wed, Apr 8, 2009 at 2:48 PM, David Bateman <address@hidden> wrote:
> Jaroslav Hajek wrote:
>>
>> I'm not sure about Windows, but under Linux even MEX compiled files
>> contain links to libcruft, liboctave & liboctinterp, which IMHO makes
>> them derivatives of Octave. The sources can be distributed under any
>> license, if they don't contain Octave-specific stuff.
>>
>>
>
> Yes, but theoretically the MEX compiled for Octave can be used with Matlab,
> and thus can be licensed which any license. This is like browser plugins,
> and is what is explicitly written in the FAQ clause propose by John. See
> clause 1 for the conditions of using a MEX...
>

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).

cheers

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