read -p "Do you want to continue [Y/n]?" BOOLEAN
http://netkiller.github.io/shell/index.html
case $BOOLEAN in
[yY][eE][sS])
echo 'Thanks' $BOOLEAN
;;
[yY]|[nN])
echo 'Thanks' $BOOLEAN
;;
'T'|'F')
echo 'Thanks' $BOOLEAN
;;
[Tt]ure|[Ff]alse)
echo 'Thanks' $BOOLEAN
;;
*)
exit 1
;;
esac
