How to implement a stdin, stdout wrapper?

Question

I have an interactive program that runs stdin and stdout. I need to create wrapper that will send X to it\'s stdin, check that it prints Y and then redirects wrapper\'s stdin an

Answer 1

Expect is made for automating the running of other programs - essentially you write something like, in plain text,

Start this program. When it prints out the word "username", send it my username. When it sends "password", send it my password.

It's really great for driving other programs.