OS

#!/bin/bash


#trap USR1 signal

function on_usr1() {
    read line < `cat my_conf`
    echo $line > /dev/tty2
    echo "Got SIGUSR1 !"
}

trap on_usr1 SIGUSR1

#trap Errors

error() {
  message="$2"
  echo "Error : $message" >> /var/log/my_script.log
}

trap 'error ${LINENO}' ERR

#Check backport

if [ ! "$(cat /etc/apt/sources.list|grep backports)" ] ;then
        echo "Adding backports repository ..."
        echo "deb http://archive.ubuntu.com/ubuntu/ `lsb_release -cs`-backports main restricted universe multiverse" >> /etc/apt/sources.list
fi

#Check for tar package

if [ ! "$(dpkg --get-selections|grep ^tar)" ] ;then
    apt-get install -y tar
fi

#Report top proccesses (async)
function report() {
    t=$( ps -aux --sort size|head -n 5 )
    echo $t > /dev/tty1
}
export -f report

watch -n 3 bash -t -c report & > /dev/null &

#Backup every 500 seconds
while [ true ] ; do
    echo "Backing up ..."
    tar -czf /root/backup_`date`.tar.gz /etc

    sleep 500
done