Shell Programming and Scripting

#!/bin/sh
 cleanup()
 {
   echo "Caught Signal ... Terminated."
   exit 1
 }
        ...       
                  
        while [ 1 ]
 do
 # enter the optional parameter if we need to
         set -m
         #invoke perl script in background
         ${HOME}/${PROCESS}.pl ${OPTIONAL} 2>&1 > $LOGFILENAME &
         #check exit status
         status=$?
         if [ $status -ne 0 ]
         then
                 echo ${PROCESS}.pl ${OPTIONAL} Job fails with status $status
                 exit $status
         fi
         # write the PID into files
         echo $! > ${PID_DIR}/${PROCESS}.perl
         chmod 755 ${PID_DIR}/${PROCESS}.perl
         
         # then bring the job to foreground
         fg %+ 2>/dev/null
         trap 'cleanup' 2 9 15 17 19 20
         sleep ${SLEEP};
 done
 exit 0

while [ 1 ]
do
# enter the optional parameter if we need to
set -m
${HOME}/${PROCESS}.pl ${OPTIONAL} 2>&1 > $LOGFILENAME &
#check exit status
status=$?

if [ $status -ne 0 ]
then
echo ${PROCESS}.pl ${OPTIONAL} Job fails with status $status
exit $status
fi
echo $! > ${PID_DIR}/${PROCESS}.perl
chmod 755 ${PID_DIR}/${PROCESS}.perl
cat ${PID_DIR}/${PROCESS}.perl | ${MAIL_BIN} -s "\"${MAIL_HEADING1}\"" ${MAIL_LIST}
fg %+
cat ${PID_DIR}/${PROCESS}.perl | ${MAIL_BIN} -s "\"${MAIL_HEADING2}\"" ${MAIL_LIST}
sleep ${SLEEP};
done
exit 0