--- a/protocol.cpp	Sat Sep 08 19:43:08 2018 +0200
+++ b/protocol.cpp	Thu Nov 29 22:30:11 2018 +0100
@@ -1,3 +1,21 @@
+/**
+ * Relational pipes
+ * Copyright © 2018 František Kučera (Frantovo.cz, GlobalCode.info)
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
 /*
  * The relpipe-lib-protocol.cpp is a header-only C++ library.
  * Generated .so file is quite useless and it is not needed to compile this library.