diff --git a/check_proc_mem b/check_proc_mem
index f553f39aa31b9eae610fc34f313bbeee54b97f7a..91b2bbe26a082ab9e07d87cabb145204523c57ea 100755
--- a/check_proc_mem
+++ b/check_proc_mem
@@ -12,6 +12,7 @@
 # ----------------------------------------------------------------------
 # 2020-03-02  v1.0  initial version
 # 2020-03-05  v1.1  <axel.hahn@iml.unibe.ch> switch to ph.* helper functions
+# 2023-02-13  v1.2  <axel.hahn@unibe.ch>     some shell fixes
 # ======================================================================
 
 # --- tmp files for internal usage
@@ -30,19 +31,19 @@ typeset -i iCountCritical=0
 
 rm -f $tmpfile $tmpfile2 $outCritical $outWarning 2>/dev/null
 
-. `dirname $0`/inc_pluginfunctions
+. $(dirname $0)/inc_pluginfunctions
 
 # ----------------------------------------------------------------------
 # MAIN
 # ----------------------------------------------------------------------
 
 # set default / override from command line params
-typeset -i iWarnLimit=`     ph.getValueWithParam 100 w "$@"`
-typeset -i iCriticalLimit=` ph.getValueWithParam 500 c "$@"`
+typeset -i iWarnLimit=$(     ph.getValueWithParam 100 w "$@")
+typeset -i iCriticalLimit=$( ph.getValueWithParam 500 c "$@")
 
 # --- read processlist and create helper table
 ps -yle >$tmpfile
-for processname in `cat $tmpfile | awk {'print $13'} | sort -u | fgrep -v "/"`
+for processname in $(cat $tmpfile | awk {'print $13'} | sort -u | grep -Fv "/")
 do
     #echo -n "$processname; ">>$tmpfile2
     ps -ylC $processname | awk '
@@ -54,10 +55,10 @@ done
 # --- check limits
 while read line 
 do
-    typeset -i iSizeMB=`echo $line | awk '{ print $2 }' | sed "s#\..*##"`
+    typeset -i iSizeMB=$(echo $line | awk '{ print $2 }' | sed "s#\..*##")
     if [ $iSizeMB -ge $iWarnLimit ]; then
-        processname=`echo $line | awk '{ print $1 }'`
-        processcount=`echo $line | awk '{ print $3 }'`
+        processname=$(echo $line | awk '{ print $1 }')
+        processcount=$(echo $line | awk '{ print $3 }')
         if [ $iSizeMB -ge $iCriticalLimit ]; then
             iCountCritical=$iCountCritical+1
             echo "Critical: $iSizeMB MB - $processname ($processcount)" >>$outCritical