asking a password in a makefile.

Makefile.ask_passwd

ask_password:
	@$(eval PASSWORD=$(shell stty -echo; read -p "Password: " pwd; stty echo; echo $$pwd)) 
  echo $(PASSWORD)

ask_password_twice:
	while true; do \
	    read -s -p "Password: " password; \
	    echo; \
	    read -s -p "Password (again): " password2; \
	    echo; \
	    [ "$$password" = "$$password2" ] && break || echo "Please try again"; \
	done && echo $$password