Re: [Chicken-users] Eggs and licensing?

[Peter Bex]

On Tue, Mar 04, 2008 at 10:47:18PM -0800, Robin Lee Powell wrote:
> 
> I apologize if the answer to this question is obvious; it isn't to
> me.
> 
> If I use an egg in my code (in the sense of "(require-extension
> egg)") but do not modify or redistribute it in any way (i.e. my code
> generates a website), and the egg is GPLd, does that infect my code?
> I gather there's some provision for linking to GPLd stuff rather
> than actually using it as code qua code, but I don't understand it
> very well.

First off, there's a difference between GPL and LGPL.  I wanted to
say most eggs are not GPL but LGPL but a quick overview of the
Eggs Unlimited page seems to indicate that this is not true, which
is a shame IMHO.  Anyway, the LGPL (Lesser/Library GPL) allows
linking your code to the LGPLed code without you needing to open
your code.

Furthermore, the GPL states that when you _redistribute_ the work
you need to provide the code under the same license (or a written
offer for this code), but with a website you do *not* redistribute
the work.  You keep the code on your machine, you can change it
and you will not have to open your code (if you keep modifications
to yourself, nobody forces you to give those back) because your
users will only get the _output_ of the modified code, which does
not fall under the licensing restrictions of the GPL.

There is a modified form of the GPL called the Affero GPL (see
http://www.fsf.org/licensing/licenses/agpl-3.0.html) which is
designed to close this "hole" in the GPL.  If anyone would want
to prevent you from using modified code like described above
he will have to license his code under the AGPL.

See also the GPL FAQ entry:
http://www.fsf.org/licensing/licenses/gpl-faq.html#UnreleasedMods

Of course, I am not a lawyer so if you're really worried about this
you might want to consult one.  Because you're intending to build
your business on this, it would be money well spent.

> I want to start a closed-source, commercial website, so GPL
> infection is totally not OK.
> 
> Having said that, if anything I do is worth Egging, I'll BSD or PD
> it and give it back to the community; I'm not interested in being a
> jerk, just interested in being able to make money.  :D

Great! :)  It's always cool to see people using Scheme in a commercial
setting.

Cheers,
Peter
-- 
http://sjamaan.ath.cx
--
"The process of preparing programs for a digital computer
 is especially attractive, not only because it can be economically
 and scientifically rewarding, but also because it can be an aesthetic
 experience much like composing poetry or music."
                                                        -- Donald Knuth

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