Shell Programming and Scripting

if [ $# = 0 ]
then
     echo "$USAGE"
     exit 1
fi

while getopts lfso: c
do
   case $c in
   l)      tail -$1 /etc/passwd
           exit 2;;
   f)      head -$1 /etc/passwd
           exit 3;;
   s)      grep $1 /etc/passwd | cut -d: -f7
           exit 4;;
   o)     OARG=$OPTARG;;
      \?) echo "$USAGE"
          exit 5;;
   esac
   done
shift `expr $OPTIND - 1

if [ $# = 0 ]
then
     echo "$USAGE"
     exit 1
fi

while getopts l:f:s:o: c
do
   case $c in
   l)      tail -${OPTARG} /etc/passwd
           exit 2;;
   f)      head -${OPTARG} /etc/passwd
           exit 3;;
   s)      grep ${OPTARG} /etc/passwd | cut -d: -f7
           exit 4;;
   o)     OARG=$OPTARG;;
      \?) echo "$USAGE"
          exit 5;;
   esac
   done
shift `expr $OPTIND - 1