#!/bin/bash

grep "Red Hat" /etc/system-release > /dev/null
redhat=$?
grep "CentOS" /etc/system-release > /dev/null
centos=$? 
grep "Rocky Linux" /etc/system-release > /dev/null
rocky=$? 

if [ ${redhat} == 0 ] 
then
	result=`cat /etc/system-release | sed -e s/"Red Hat .*release \(.*\) (.*)"/"\1"/`
elif [ ${centos} == 0 ]
then
    result=`cat /etc/system-release | sed -e s/"(Core)"// | sed -e s/"CentOS .*release \([0-9]*\.[0-9]*\).*"/"\1"/`
elif [ ${rocky} == 0 ]
then
	result=`cat /etc/system-release | sed -e s/"Rocky Linux .*release \(.*\) (.*)"/"\1"/`
else
	result="NotsupportOS"
fi
echo -n "${result}"
