Bash ask for confirmation

read -p "Are you sure? " -n 1 -r
echo    # (optional) move to a new line
if [[ ! $REPLY =~ ^[Yy]$ ]]
then
    [[ "$0" = "$BASH_SOURCE" ]] && exit 1 || return 1 # handle exits from shell or function but don't exit interactive shell
fi

Source: https://stackoverflow.com/questions/1885525/how-do-i-prompt-a-user-for-confirmation-in-bash-script