diff --git a/functions.sh b/functions.sh
index bf4df6f..7994715 100755
--- a/functions.sh
+++ b/functions.sh
@@ -1055,7 +1055,14 @@ get_crtime() {
 
 
 is_btrfs_subvolume() {
-    sudo btrfs subvolume show "$1" >/dev/null
+    local XSUDO
+    if [ $(id -u) -eq 0 ] 
+    then
+        XSUDO=
+    else
+        XSUDO=sudo
+    fi
+    ${XSUDO:+sudo} btrfs subvolume show "$1" >/dev/null
 }
 
 convert_to_subvolume () {