Re: Releasing SW under GPL
On Thu, Nov 17, 2005 at 12:12:53AM +0100, Svante Signell wrote:
> I'm about to release some SW I've been working on for some years under a
> GPL licence and have a few questions:
> - Which text to include in the files? Is the following OK?
This looks good to me.
> * Author : xx yy
> * Copyright : xx yy, 2000-2005
> * License : GNU GPLv2 or later
> * This program is free software; you can redistribute it and/or modify
> * it under the terms of the GNU General Public License version 2 as
> * published by the Free Software Foundation;
> * Revisions : 2005-11-16, xx yy, initial GPL release
> - In the top directory is a copy of the GPL text, like gpl.txt for
> - Should the same text be included in all files? *.c, *.h and various
> other files like Makefile, README, TODO, Changelog etc.
Anything with creative content, including at least *.c. Some argue
that *.h, at least for libraries, have no creative content, or are
only API, and thus not copyrightable, but it can't hurt. *.h with
static inline functions should include such a note, for sure.
Nontrivial Makefiles also. I can't recall seeing a copyright
statement in any README, TODO or Changelog, but it couldn't hurt. I
think it is often assumed that these files are either not creative, or
are under a license comparable to the code. Presumably anyone
modifying the TODO file is working with upstream anyway..
> - Which years should the Copyright cover: All years since the beginning
> of development (2000-2005) or the current year when the release is made
> (2005 and subsequent years)? For some code many revisions have been
> made, not even resembling the original code.
All years during which nontrivial changes were made, or a date range
including those years (right?).
> - What is the difference if I write 'GPLv2 or later' or just 'GPLv2'?
> Consequences when GPLv3 is released?
Right; its a matter of whether you trust the FSF. Dynamically
changing licenses are potentially bad..
> - How to incorporate other peoples contributions, in the copyright
> statement and/or in the revision part?
Just note when people make nontrivial contributions. It is probably
best to make the note in the copyright header, as in "Copyright (C)
2005 Justin Pryzby and Svante Signell", but it would also be good to
note it near the relevent code, as in "// This section contributed by
Justin Pryzby" (where "this section" is reasonably clearly defined).
Of course other people have to agree to license their contributions in
a matter consistent with your license.
The idea is to make a code audit easy; grep -A4 -B4 -ir copyright can
be done on a fairly large source tree without too much trouble, but
its crazy disappointing if you later notice all sorts of stuff like
"This is copied almost verbatim from Foo by Bar"..Numerical Recipes
seems to turn up lots..