Re: [Gnu-arch-users] GNU Arch moves to GPL v3 or later

[Thomas Lord]

Alfred M. Szmidt wrote:
>    You're confusing the permissions notice, which allows a disjunction of
>    template licenses, with the template licenses themselves, each of
>    which individually must remain unchanged.  The "or later" phrasing is
>    simply a compact way to express what legally is a multiple license,
>    akin to the GPL+FDL licensing recommended by the FSF for code examples
>    in documentation.
>
> You clearly do not undertstand the GPL,
>
>        b. You must cause any work that you distribute or publish, that
>           in whole or in part contains or is derived from the Program
>           or any part thereof, to be licensed as a whole at no charge
>           to all third parties under the terms of this License.
>
>
> `or later' is part of the license terms, much like a the clauses of
> Bison that allow people to use the output in non-free software.
>   

I'm pretty sure you're wrong, Alfred but before I explain why:  can
you cite a source for that opinion?   Is there something in the FSF's
GPL FAQ, for example?

Exception clauses, as in Bison and some other programs, are modifications
to GPL itself.   They add "additional permissions" in the language
of GPLv3.   Anyone is free to remove those permissions.   If someone
distributes a modified Bison that mixes in code that doesn't have those
permissions, then they *must* remove the extra permissions (to 
redistribute).
Historically, this form of extra permission was implemented separately, 
on a case
by case basis.  GPLv3 directly codifies the general rules for extra
permissions, which is pretty convenient.

The "or later" language is outside of the GPL.  It is not an extra 
permissions
clause injected into the GPL.   It is part of a formal legal statement that
declares which license terms apply.  You look at some file and there is a
copyright notice:

   Copyright (C) 2007 Thomas Lord

and you want to know "on what terms was this given to me?
where can I find the terms?"   The reference to the file COPYING
and the phrase "or later" tell you where you can find the terms.
The "or" in "or later" is a technical term, with a very specific meaning:

It is easy to  explain the technical meaning of "or" through an
imagined example.   Suppose that there are two free software,
copyleft licenses called LicA and LicB.   I write some original
code and give you a copy.    My copyright notices say:

    you may use the terms of LicA or LicB.

What can you do?   You can distribute the program to a third
person as just LicA or as just LicB, assuming you otherwise
satisfy the requirements of those individual licenses.   Also,
if in distributing the program, you can simultaneously satisfy
the requirements of *both* LicA *and* LicB then you *may*
distribute just as I did, under "LicA *or* LicB".   In effect,
the law looks at your act of distribution, ponders the question
"did that take place under LicA or did that count as a LicB
distribution" and arrives at the answer "the question is moot
since the act was permitted under both licenses".

A dual licensing option like "or any later version as published by..."
is an interesting problem:  how can a copyright statement refer
to terms that haven't been written yet?   How can anyone tell
what will or won't violate those later terms?   The answer is that
it doesn't matter until the later license is released -- until that
time, it doesn't apply to anything, and therefore can't be violated.
But, after, say, GPLv3 is released, the next time I want to distribute
some "GPLv2 or later" code, I have to be sure that the distribution
is permitted under GPLv3 *or else I have to remove the "or later"*.

See?

-t