Chek PID pada Linux

# ps -ef | grep -i "firefox" | grep -v grep | awk '{print $2}'

#!/bin/bash

#Ganti dengan nama aplikasi yang mau dikill
APP=chek

CHECK=`ps -ef | grep -i "$APP" | grep -v grep | awk '{print $2}' | wc -l`
if [ $CHECK -eq 0 ]; then
echo "No Process"; exit
elif [ $CHECK -gt 1 ]; then
echo "Double name Process. Try again and be more specific."; exit
fi

PID=`ps -ef | grep -i "$APP" | grep -v grep | awk '{print $2}'`
echo "killing pid $PID"
kill $PID
exit 0