Re: [Savannah-hackers] savannah.gnu.org: submission of nethack-el

[Ryan Yeske]

Loic Dachary <address@hidden> writes:

> Ryan Yeske writes:
>
>  > To what extent are they incompatible?  Do you mean that the two
>  > licenses cannot be used within the same code base?
>
>       Yes. The compatibility between GPL v1 and GPL v2 is
> implemented by the "or any later version" of the copyright
> notices. But Nethack developers refused this phrase and refused to
> upgrade to GPL v2.

OK.

>  > However, the included patch, enh-331.patch, modifies the Nethack
>  > C sources and maintains the license the Nethack developers have
>  > chosen (I don't think we have much of a choice here).  Our
>  > changes to the
>
>       The choice is yours, always. You could either say they are
> under the GNU GPL v2 or the Nethack license. It may be the case that
> Nethack developers will refuse your contribution if released under
> the GNU GPL v2 but they cannot force you to change the license. They
> can put pressure on you to change the license of your contribution
> to Nethack license.

The ideal situation would be to have our "lisp window port" changes in
the main Nethack distribution, and we could focus on just hacking the
elisp, but that isn't something is going to happen right now, as
everything is still subject to quite a bit of change.

>       There is no incompatibility in this case, yes. The
> incompatibility only touches the nethack patch, unless you clearly
> states that it is released under the Nethack license. In the current
> tarbal there is no such statement, therefore one will think it is
> released under the same license as the rest of the files.

My original understanding of it was that it wasn't the patch per se
that carried the license but rather the code that resulted from
applying the patch to existing licensed code.  For example, the
enh-331.patch modifies nethack-3.3.1/src/windows.c, which is licensed
under the Nethack license.  Clearly, not being the copyright holders,
we can't change the license of that file.  Again, by my understanding
of it, the terms by which we can change and distribute changes to
their code is defined by the license of their code.  So I guess I'm a
bit confused on this point.  I never thought of patches as being
licensed, which is why I thought that we had no choice.

>  > our elisp code is practically (but not technically) dependent on
>  > the existence of a Nethack binary with our patch applied.  In
>  > other words, our GPLv2 elisp code is useless without a Nethack
>  > binary compiled with the "lisp" window port.  I'm not clear on
>  > the law here.
>
>       That is not an issue here. It would be if Nethack was not free
> software. But Nethack is Free Software although released under a
> license that is incompatible with the GNU GPL v2.

OK, I understand that.

>  > OK, so where does that leave us with respect to distributing a
>  > package which includes a patch to the Nethack C sources?
>
>       If the patch is under the GNU GPL v2 (as it now is the case)
> it is not a problem to host it on Savannah. But I did not want to
> trick you into this, hence I ringed the bell. You need to make a
> choice. Either to have the patch under the Nethack license and not
> be able to host the patch on Savannah. Or have the patch under the
> GPL v2 license and create a license incompatibility issue on Nethack
> modified with your patch.

So the patch can/does carry a license, and (assuming the patch is GPL v2)
when it is applied by the user, the result will be a license
incompatibility?  And consequently, the user who applies the patch
will be unable to redistribute the modified source?

>       :-) I hope this clarifies things. Frankly I never quite
> understood why the Nethack team is refusing GPL v2. From the
> discussions I had with them it seems more like superstition rather
> than true reasoning. Oh well.

It all seems a bit frustrating to me...I see the spirit of both
licenses as being the same: "Do with the code whatever you want, but
don't deprive anyone else of the same privilege".

We would very much like to have nethack-el hosted on Savannah, but
would not like to create any license incompatibilities elsewhere.
Given what you say, we can't really do both :(.

Ryan