diff --git a/check_cpu b/check_cpu
index d82a21933e6684acc5eb51f2a629fbd590924288..0f5bc3e4f38cb3fbaa21b5ee3d648717f40bac45 100755
--- a/check_cpu
+++ b/check_cpu
@@ -21,13 +21,14 @@
 # 2022-04-14  v1.10 <axel.hahn@iml.unibe.ch> show consuming cpu processes with top and ps
 # 2022-08-29  v1.11 <axel.hahn@iml.unibe.ch> replace pipe to prevent start of metrics section
 # 2022-08-29  v1.12 <axel.hahn@iml.unibe.ch> fix: replace pipe
+# 2023-02-13  v1.13 <axel.hahn@iml.unibe.ch> small shell fixes
 # ======================================================================
 
 
 . $(dirname $0)/inc_pluginfunctions
 
 self_APPNAME=$( basename $0 | tr [:lower:] [:upper:] )
-self_APPVERSION=1.12
+self_APPVERSION=1.13
 
 # ----------------------------------------------------------------------
 # functions
@@ -114,7 +115,7 @@ typeset -i iMinCpuUsageToShowProcesses=$(  ph.getValueWithParam 50 p "$@")
 # top -b -n 1 | head -5 | grep "^\%Cpu" >$tmpfile
 # FIX read cpu from 2nd output of top
 
-data=$( top -b -n 2 -d 0.1 | grep -i "^\%Cpu" | tail -1 | cut -f 2- -d ':' | tr ',' "\n" )
+data=$( top -b -n 2 -d 0.1 | grep -i "^%Cpu" | tail -1 | cut -f 2- -d ':' | tr ',' "\n" )
 
 cpuUser=$(   echo "$data" | grep "us" | awk '{ print $1 }' )
 cpuSystem=$( echo "$data" | grep "sy" | awk '{ print $1 }' )
@@ -160,14 +161,17 @@ echo "$plist" | grep "[0-9]" >/dev/null \
     && echo "$plist" | tr '|' ':'
 
 # v1.7: show most consuming processes if usage is > nn %
-typeset -i iUsed=$( echo $cpuNonIdle | cut -f 1 -d '.' )
+typeset -i iUsed
+iUsed=$( echo $cpuNonIdle | cut -f 1 -d '.' )
 if [ $iUsed -gt $iMinCpuUsageToShowProcesses ]; then
   echo
   echo "CPU usage is higher $iMinCpuUsageToShowProcesses percent ... showing most consuming processes"
   echo "output of top :"
   topout=$( top -b -n 1 -d 0.1 )
-  typeset -i iStart=$( echo "$topout" | grep -n "PID.*USER" | cut -f 1 -d ':' )
-  typeset -i iEnd=$iStart+5
+  typeset -i iStart
+  iStart=$( echo "$topout" | grep -n "PID.*USER" | cut -f 1 -d ':' )
+  typeset -i iEnd
+  iEnd=$iStart+5
   echo "$topout" | sed -n "${iStart},${iEnd}p" | tr '|' ':' 
   echo
   echo "output of ps:"