Re: Revised LaTeX Project Public License (LPPL)
Frank Mittelbach <email@example.com> writes:
> Jeremy Hankins writes:
> > I'm not all that knowledgeable about latex, but I do use it and I have
> > read the discussions here. So correct me if I'm wrong, but my
> > understanding is that a package file has a very intimate level of
> > contact with LaTeX-Format (and, in fact, other package files that are
> > currently loaded). It may rewrite other bits of code loaded by the
> > TeX binary, and even if that's not happening it has virtually
> > (completely?) unrestricted access (i.e., not restricted to an API) to
> > the other code.
> all statements correct, it is virtually completely unrestricted access
> > Either of those seems to raise the possibility of creating a derived
> > work. Whether anything's compiled and whether anything resembling
> > linking is happening isn't really the issue.
> well that i don't believe at least not as long a as such packages are really
> separate entities that are only put together for a moment during use.
To be honest, I don't really know for sure. But the tricky part is
that I don't know that anyone else does either. The fundamental
question (which isn't technical at all) is when two works, used in
conjunction, become a derived work. I'm sure lots of other folks can
give you a more knowledgeable answer, but in the end it boils down to
a big question mark with lots of theories. At some point they clearly
do (static linking is pretty well accepted as such a point). Other
points (dynamic linking, which the FSF supports as creating a derived
work) may be less clear, but my impression is that most people, even
if they disagree, aren't certain enough to want to argue against it in
Once they become a derived work the copyright of both works "infects"
that of the other -- the GPL didn't invent it, it just uses this fact.
But one of the ideas (I think RMS supports this view, but I can't find
a reference) is that the degree of conectedness -- i.e., how intimate
the connection is, is a good indicator of whether a derived work is
created. If that's the case, LaTeX files would clearly create a
derived work, since they're if anything more intimately connected than
even static linking.
Another argument for LaTeX files creating a derived work is the simple
fact that, in at least some cases, they literally rewrite some of the
code. This is a modification, which seems pretty clearly to make it a
> if that would be legally true then by the same argument then EvilDoer could
> dream up EvilLicense put it on on evil.el use it together with emacs and then
> claim that EvilLicense has an effect on emacs
What would happen in that you wouldn't be able to distribute evil.el.
It and emacs (or perhaps not emacs, since it's an interpreter which is
a bit of a special case, but some other GPL'd elisp files maybe)
together would be a derived work and thus to distribute you'd have to
be able to meet the terms of the GPL for evil.el.
In the end I (as an ignorant, non-lawyer) suspect that there is no
clear answer to this question. But precisely because it's not clear
anyone writing GPL'd LaTeX files ought to be aware of the possible
consequences. Naturally, this problem would disappear if the LPPL
were GPL compatible, which is a reason to shoot for that if possible.
But it seems pretty clear that that's not compatible with your goals,
so that's not possible.
Jeremy Hankins <firstname.lastname@example.org>
PGP fingerprint: 748F 4D16 538E 75D6 8333 9E10 D212 B5ED 37D0 0A03