Re: Plugins, libraries, licenses and Debian

[mru@kth.se (Måns Rullgård)]

Arnoud Engelfriet <galactus@stack.nl> writes:

> M?ns Rullg?rd wrote:
>> sure.  I personally feel uncomfortable with applying a license that
>> 1) nobody knows what it means, and 2) the FSF can change the terms of
>> at any time.
>
> They can't. What most people do is say "This program is free
> software; you can redistribute it and/or modify it under the terms of
> the GNU General Public License as published by the Free Software
> Foundation; either version 2 of the License, or (at your option) any
> later version."
>
> This way the FSF can introduce a new version of the GPL and I
> can use any software with the above text under that new version.
> But if the software is only licensed under GPLv2, there is no
> way I can use it under GPLv3 without the author's permission.
> See e.g. the Linux kernel.

I have seen claims that attempts to restrict the choice to one
particular version are invalid.  I can't remember the details right
now.

GPL section 9 contains this confusing paragraph:

  Each version is given a distinguishing version number. If the
  Program specifies a version number of this License which applies to
  it and "any later version", you have the option of following the
  terms and conditions either of that version or of any later version
  published by the Free Software Foundation. If the Program does not
  specify a version number of this License, you may choose any version
  ever published by the Free Software Foundation.

All that seems rather obvious to me, so why write it down?  Would
there be another possible interpretation otherwise?  If that's the
case, why not mention programs that allow only one specified version?

-- 
Måns Rullgård
mru@kth.se