add comment
diff --git a/build_lxc.sh b/build_lxc.sh
index f7536d4..657dd8a 100755
--- a/build_lxc.sh
+++ b/build_lxc.sh
@@ -67,6 +67,7 @@
 # stack requires)
 echo "stack ALL=(ALL) NOPASSWD: ALL" >> $ROOTFS/etc/sudoers
 
+# Gracefully cp only if source file/dir exists
 function cp_it {
     if [ -e $1 ] || [ -d $1 ]; then
         cp -pr $1 $2