macOS: Notify when successful SSH login

ssh-login-notify.sh

#!/bin/bash
machine_hostname=$(hostname -s)
while read line; do
    if [[ $line == *"$machine_hostname sshd:"* ]]
    then
        user=$(echo $line | sed -e 's/.*sshd:\(.*\)\[priv.*/\1/' | tr -d '[:space:]')
        process=$(echo $line | sed -e 's/.*USER_PROCESS:\(.*\)tty.*/\1/' | tr -d '[:space:]')
        logger -p 5 -t "ssh-login-notify" -s "ssh-login-notify: user \"$user\" (process: \"$process\")"
        osascript -e "display notification \"user: $user\nprocess: $process\" with title \"SSH Login: $user\""
    fi
done

Usage:

chmod +x ssh-login-notify.sh.sh
tail -F /var/log/system.log | ./ssh-login-notify.sh.sh