diff --git a/run.sh b/run.sh
index 19bb198..437c397 100755
--- a/run.sh
+++ b/run.sh
@@ -1,13 +1,13 @@
-#!/bin/bash
+#!/bin/sh
 
 scriptdir=$(dirname $(realpath $0))
 
 # ============================================================
 
-if [[ $EUID -eq 0 ]]; then
+if [ "$(id -u)" -eq 0 ]; then
     echo "Running in root mode."
     $scriptdir/init_root.sh
-elif [[ $(sudo whoami) == "root" ]]; then
+elif [ "$(sudo id -u)" -eq 0 ]; then
     echo "Running in sudo mode."
     $scriptdir/init_sudo.sh
 else