wiringPi is Copyright (C) 2012-2015 Gordon Henderson. wiringPi is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License, as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. wiringPi 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 Lesser General Public License for more details. On all Debian and Raspbian systems, a copy of the GNU Lesser General Public License version 3 can be found in `/usr/share/common-licenses/LGPL-3'.