Default update scripts for Debian-based Linux distributions. See this blog post: http://blog.robseder.com/?p=13292

update.sh

#!/bin/bash

Black='\033[0;30m'
DarkGray='\033[1;30m'
Red='\033[0;31m'
LightRed='\033[1;31m'
Green='\033[0;32m'
LightGreen='\033[1;32m'
Brown='\033[0;33m'
Yellow='\033[1;33m'
Blue='\033[0;34m'
LightBlue='\033[1;34m'
Purple='\033[0;35m'
LightPurple='\033[1;35m'
Cyan='\033[0;36m'
LightCyan='\033[1;36m'
LightGray='\033[0;37m'
White='\033[1;37m'
NC='\033[0m' # No Color

Name='Debian-based System Update Utility'
Version='v1.0.0-alpha.1'

function setXtermTitle () {

    newTitle=$1

    if [[ -z $newTitle ]]
    then
        case "$TERM" in
            xterm*|rxvt*)
                PS1="\[\e]0;$newTitle\u@\h: \w\a\]$PS1"
            ;;
            *)
            ;;
        esac
    else
        case "$TERM" in
            xterm*|rxvt*)
                PS1="\[\e]0;${debian_chroot:+($debian_chroot)}\u@\h: \w\a\]$PS1"
            ;;
            *)
            ;;
        esac
    fi
}

function setStatus(){

    description=$1
    severity=$2

    setXtermTitle $description

    logger "$Name $Version: [${severity}] $description"


    case "$severity" in
        s)
            echo -e "[${LightGreen}+${NC}] ${LightGreen}${description}${NC}"
        ;;
        f)
            echo -e "[${Red}-${NC}] ${LightRed}${description}${NC}"
        ;;
        q)
            echo -e "[${LightPurple}?${NC}] ${LightPurple}${description}${NC}"
        ;;
        *)
            echo -e "[${LightCyan}*${NC}] ${LightCyan}${description}${NC}"
        ;;
    esac

    [[ $WithVoice -eq 1 ]] && echo -e ${description} | espeak
}

function runCommand(){

    beforeText=$1
    afterText=$2
    commandToRun=$3

    setStatus "${beforeText}" "s"

    eval $commandToRun

    setStatus "$afterText" "s"

}

echo -e "${LightPurple}$Name $Version${NC}"


if [[ $1 == "?" || $1 == "/?" || $1 == "--help" ]];
then
    setStatus "USAGE: sudo $0" "i"
    exit -2
fi

if [[ $(whoami) != "root" ]];
then
    setStatus "ERROR: This utility must be run as root (or sudo)." "f"
    exit -1
fi

WithVoice=0

if [[ $WithVoice -eq 1 && ($(which espeak | wc -l) -eq 0) ]];
then
    setStatus "ERROR: To use speech, please install espeak (sudo apt-get install espeak)" "f"
    exit -1
elif [[ $WithVoice -eq 1 ]];
then
    setStatus "Voice detected - using espeak." "s"
fi

if [ $(which neofetch | wc -l) -gt 0 ];
then
    echo -e -n "${Yellow}"
    neofetch
    echo -e "${NC}"
fi

if [ $(which figlet | wc -l) -gt 0 ];
then
    echo -e -n "${Yellow}"
    echo $(hostname) | figlet
    echo -e "${NC}"
fi

setStatus "Update starting..." "s"

runCommand "STEP 1 of 4: Refreshing repository cache..." "Repository cache refreshed." "sudo apt-get update -y"
runCommand "STEP 2 of 4: Upgrading all existing packages..." "Existing packages upgraded." "sudo apt-get upgrade -y"
runCommand "STEP 3 of 4: Upgrading packages with conflict detection..." "Upgrade processed." "sudo apt-get dist-upgrade -y"
runCommand "STEP 4 of 4: Cleaning up unused and cached packages..." "Package cleanup complete." "sudo apt-get autoclean -y && sudo apt-get autoremove -y"

setStatus "Update complete." "s"

# if [ $(which rpi-update | wc -l) -gt 0 ]; then
#         echo -e "[${LightGreen}+${NC}] ${LightGreen}Raspberry Pi Detected.${NC}"
#         [[ $WithVoice -eq 1 ]] && echo -e "Raspberry Pi Detected." | espeak
#         echo -e "[${LightGreen}+${NC}] ${LightGreen}Updating the Raspberry Pi firmware to the latest (if available)...${NC}"
#         [[ $WithVoice -eq 1 ]] && echo -e "Updating the Raspberry Pi firmware to the latest." | espeak
#         sudo rpi-update
#         echo -e "[${LightGreen}+${NC}] ${LightGreen}Done updating firmware.${NC}"
#         [[ $WithVoice -eq 1 ]] && echo -e "Done updating firmware." | espeak
# fi


if [ -f /var/run/reboot-required ]; then
    setStatus "PLEASE NOTE: A reboot is required." "i"
    setStatus "Would you like to reboot now?" "?"
    [[ $WithVoice -eq 1 ]] && echo -e "Would you like to reboot now?" | espeak
    while true; do
        read -e -r -p "> " choice
        case "$choice" in
            y|Y )
                setStatus "Rebooting..." "i"
                sudo reboot
                break
            ;;
            n|N )
                setStatus "Done." "+"
                break
            ;;
            * )
                setStatus "Invalid response. Use 'y' or 'n'." "-"
            ;;
        esac
    done

else
    setStatus "No reboot is required." "i"
fi

setStatus "System update complete." "+"

Changed the last sector with:

`if [ -f /var/run/reboot-required ]; then
echo -e "[${LightCyan}${NC}] ${LightCyan}PLEASE NOTE: A reboot is required.${NC}"
sudo reboot
else
echo -e "[${LightCyan}${NC}] ${LightCyan}No reboot is required.${NC}"
exit 0
fi

done`

Thanks for the nice script!!! ;)