diff --git a/pkgs/opengl/auto-virtualgl.sh b/pkgs/opengl/auto-virtualgl.sh
index 18bd597..c73b742 100755
--- a/pkgs/opengl/auto-virtualgl.sh
+++ b/pkgs/opengl/auto-virtualgl.sh
@@ -79,6 +79,9 @@ VGL_filterS() {
 #
 # These consume a stream of escaped new-line separated items
 #
+
+# Return true iff given command returns true for some item
+#
 VGL_anyS() {
   declare command=("$@")
   while read next; do
@@ -90,6 +93,7 @@ VGL_anyS() {
 }
 
 
+
 # Tests for the filter transformer
 #