Excerpts from Alexander Duscheleit's message of 2010-08-27 21:31:29 +0200:
On Fri, 27 Aug 2010 15:22:03 +0100 Peter Lewis <pete@muddygoat.org> wrote:
On Thursday 26 August 2010 at 18:57 Alexander Duscheleit wrote:
Philipp Überbacher <hollunder@lavabit.com> wrote:
Besides that, I think it's future proof. One issue though is that the meaning of: ('GPL2' 'GPL3') isn't the same as: 'GPL2 or later' It only is practically the same because there's nothing beyond GPL3 yet.
Just out of curiosity...
Supposed, there is a GPL4 around at some time in the future. Now, if I receive some software under the terms of "GPL2 or later", would it be in my right, to redistribute said software under "GPL3 only" as opposed to "GPL3 or later"?
Yes, this is your right. Just as you can take some software released under "GPL2 or at your option, any later version" and redistribute it under GPL3 only. This is "your option". You do not have the pass the option on, since that doesn't form part of the copyleft.
Of course, someone else can redistribute the original under GPL2 only, GPL4 only, GPL2 "or later" or GPL3 "or later". That's their option :-)
That was my understanding, too. :-)
It gets more interesting, when I make changes to my redistributed software, though. If i understand correctly, if upstream is GPL2+ and my version is GLP3 only, I effectively either cut upstream out from my changes or force them to upgrade their version to GPL3 only (not even GPL3+). This looks to me, like I could violate the spirit of the GPL through the GPL itself. (Poaching in lawyers waters as a layman sure is fun :-D.)
Jinks
Someone in #fsf on freenode might be able to answer you. I guess the answer would be: "optimally there would be no such thing as GPLvN only". -- Philipp -- "Wir stehen selbst enttäuscht und sehn betroffen / Den Vorhang zu und alle Fragen offen." Bertolt Brecht, Der gute Mensch von Sezuan