#!/bin/sh
while true
do
  start_your_program
  RC=$?          # return code
  if [ $RC -gt 0 ]
  then
    date >> /var/log/your_log_file
    echo "ABNORMAL program termination, rc = $RC" >> /var/log/your_log_file
    echo "terminated at `date`, restarting | mail -s "Problem with zzz" root
    sleep xxx
  else
    date >> /var/log/your_log_file
    echo "Normal program termination, rc = $RC" >> /var/log/your_log_file
    sleep yyy
  fi
done