The GtkRadiant sources as originally released under the GPL license.

setup/openurl.sh

@@ -0,0 +1,14 @@
+#!/bin/sh
+# use this script to customize the way the engine should open URLs
+
+for test_browser in mozilla netscape
+do
+  browser=`which $test_browser`
+  if [ "x$browser" != "x" ]
+  then
+    $browser -remote "openURL($1,new-window)" || $browser "$1"
+    exit
+  fi
+done
+
+xterm -e lynx "$1"