Re: [eigen] legal question

[Benoit Jacob <jacob.benoit.1@xxxxxxxxx>]

2010/8/16 Gael Guennebaud <gael.guennebaud@xxxxxxxxx>:
> On Tue, Aug 3, 2010 at 6:12 PM, Benoit Jacob <jacob.benoit.1@xxxxxxxxx> wrote:
>> 2010/8/3 Rodney Sparapani <rsparapa@xxxxxxx>:
>>> On 08/ 3/10 10:58 AM, Benoit Jacob wrote:
>>>>
>>>> Do you mean the doxygen-generated class docs? What is the problem with
>>>> CC-BY on them?
>>>>
>>>> Also, isn't it better to have a single license governing all our docs,
>>>> so that e.g. an archive of all our docs would be governed by a single
>>>> license?
>>>>
>>>> Benoit
>>>
>>> Hi Benoit:
>>>
>>> Having worked on several FOSS projects, it seems that one license is best,
>>> especially for things like snippets which have already been brought
>>> up in this thread.  By the way, I must have missed it, but was there
>>> some reason that MIT or BSD licenses were not considered?
>>
>> No particular reason: it felt natural to consider CC for docs, but you
>> seem to be right: there is no problem about releasing docs under
>> MIT/BSD license, is there?
>>
>> That would be a nice choice, because if we choose a very liberal
>> license for our docs for the sake of simplicity, then nothing beats
>> MIT/BSD in this respect.
>
> yes the MIT license seems to be well appropriate here.

Cool that we agree on a license for documentation. I think we can
actually relicense the documentation under MIT right now, if other
people agree.

Let's look at the potential license conflicts with our code's LGPL license:

1. inclusion of snippets from Eigen's own code: this is the toughest
issue, fortunately most of our documentation pages include only such
trivial code snippets that it shouldn't be an issue in practice. There
is 1 big exception: I03_InsideEigenExample.dox. Since it is out of
date anyway, we could disable it for now until a solution is found.
(Find a license applicable to it and compatible with the LGPL license
on our code, and publish this page separately e.g. on our
website/wiki).

2. license for the examples under doc/examples and doc/snippets.
There, I suggest we put a LICENSE and a README file in these
directories saying they are all MIT-licensed. At least for the
snippets, we have a very good technical reason to not include license
info in every file.

3. license for the doxygen-generated class doc pages. I don't think
they include any significant bit of Eigen source code. I don't have a
precise idea of the status of generating with doxygen from
LGPL-licensed files, but other projects don't care much about that,
and at least the spirit of the LGPL is to allow that (i.e. allow _use_
by everybody). If there really is an issue, we can play again on
Section 3 of the LGPL, I guess, which makes it behave more or less
like MIT for material coming from header files, as long as no forking
is done.

4. license for our manually written .dox pages. No problem here, we
just have to put a license info comment at the top of each of them.

All in all, while it's not 100% simple, I think we definitely can
license our docs under MIT if other authors here agree. The most
nontrivial question is what to do about I03_InsideEigenExample.dox and
are there other pages including significant portions of Eigen code?

Cheers,
Benoit

>
> gael
>
>>
>> Benoit
>>
>>>
>>> --
>>> Rodney Sparapani       Center for Patient Care and Outcomes Research
>>> Sr. Biostatistician               http://www.mcw.edu/pcor
>>> 4 wheels good, 2 wheels better!   Medical College of Wisconsin (MCW)
>>> WWLD?:  What Would Lombardi Do?   Milwaukee, WI, USA
>>>
>>>
>>>
>>>
>>
>>
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