diff --git a/sync.sh b/sync.sh
index 4b8f01a..89ed355 100644
--- a/sync.sh
+++ b/sync.sh
@@ -7,7 +7,7 @@ osreleaseprop() {
 elevated() {
     s=${SUDO:-sudo}
     if [ ! "$s" = "none" ]; then
-        if ! which $s &> /dev/null; then
+        if ! command -v $s &> /dev/null; then
             echo "command \"$s\" not found"
             exit 1
         fi