task3.sh

caution_message (){
    echo -e "
--------------------------------------------------------
                        CAUTION
--------------------------------------------------------
You are using a root user which is not a recommended
practice as those users have the potetial to cause 
severe damages to the systems under many circunstances.
For being the most privileged accounts on Unix/Linux,
their use have to be restricted and avoided at all costs.
Every single command/program a root user fires inherites
its powerful permission on the system. That means that if
you fire a wrong command when logged as a root user or if 
the program you're using does something it shouldn't for
any reason (a bug, an exploitation), it won't have any
restriction on what it could affect. Moreover, if you,
for any reason, let a system logged with a root user
without supervision, someone can have full power over it,
being able to cause damage on purpose or accidentaly.
----------------------------------------------------"
}

continue (){
    echo -ne "\nProceed (y/n): " >&2
    read answer
    echo $answer | tr '[:upper:]' '[:lower:]' # Keeping lower canse of user answer
}

if [ `id -u` -eq $ROOT_USER_ID ]
then
    caution_message
    answer=$(continue)
    while [ "$answer" != "y" -a "$answer" != "n" ] # Checking if user have answer 'y' our 'n'
    do
        echo -e "\nThe answer $answer is invalid. Answer just y or n."
        answer=$(continue)
    done
    if [ "$answer" = "y" ] # Logging information of user who decides to proceed
    then
        username=`whoami`
        echo -e "Timestamp:                          `date`" >> $LOG_DIRECTORY/$username
        lslogins `whoami` >> $LOG_DIRECTORY/$username
        exit 0
    else
        logout &>/dev/null # Works only on login shells
    fi
fi