All source code files are subject to the GNU General Public License version 2 or later. You should have received a copy of the GPL in the file GPL.txt. All Demo files and the acceptance tests are under public domain. You are explicitly encouraged to use these as templates or starting points for your own programs. If you wish to use parts of the code for a project with a GPL-incompatible license, send a mail to the user list and we will try to sort it out.