diff --git a/check b/check
index d2995c9..31c14bd 100755
--- a/check
+++ b/check
@@ -17,7 +17,7 @@ if [ "`whoami`" != "root" ]; then
 fi
 
 RUNLEVEL=`runlevel | cut -f 2 -d ' '`
-[ -n "$RUNLEVEL" ] && RUNLEVEL=0
+[ "x$RUNLEVEL" == "x" ] && RUNLEVEL=0
 if [ $RUNLEVEL -eq 0 ] || [ $RUNLEVEL -eq 6 ]; then
   echo "Arret ou reboot en cours : on sort"
   exit