--- a/src/sockets.cc
+++ b/src/sockets.cc
@@ -1,3 +1,19 @@
+// Copyright (C) John Swensen <jpswensen@comcast.net>
+// Copyright (C) 2007 Tom Holroyd <tomh@kurage.nimh.nih.gov>
+// Copyright (C) 2009 Paul Dreik <slask@pauldreik.se>
+// 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/>.
 // C++ STL includes
 #include <cstdio>