Simple steps to attach the GNU Public License (GPL) to your project

Here's the simple steps to attach a GPL license to your source files (written after requests by DiggClone and Bandnet):

For your own project, just add the following text-notice to the header/first section of each of your source-files, commented out in whatever way your language uses:

----------------following is the notice-----------------
/*
* Your Project Name - -you slogan-
* Copyright (C) 2007 - 2007 Your Name
*
* 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 program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
----------------------------------------------
the "2007 - 2007" needs to be adjusted to "year when you gave it the license in the first place" - "current year".

Then put the file gpl.txt into the source-folder or a docs folder: http://www.gnu.org/licenses/gpl.txt

If you are developing together with other people, you need their permission to put the project under the GPL.

------

Just for additional Info, I found this license comparision paper by sun: http://mediacast.sun.com/share/webmink/SunLicensingWhitePaper042006.pdf

And comments to it: http://blogs.sun.com/webmink/entry/open_source_licensing_paper#comments

It does look nice, but it misses one point:

GPL is trust: Contributors can trust, that their contributions will keep helping the community, and that the software they contribute to will keep being accessible for the community.

(That's why I decided some years ago to only support GPL projects. My contributions to one semi-closed project got lost, because the project wasn't free and the developer just decided not to offer them anymore, and I could only watch hundreds of hours of work disappear, and that hurt.)

Best wishes,
Arne
PS: If anything's missing, please write a comment!