Exploring Expect

Exercises

1. On page 167, I described a convenient but simplistic procedure for enabling diagnostics. Write a procedure that uses keywords to select subsets of information to be printed.

2. Write a procedure called assert, patterned after the one in the C language. The procedure should evaluate an expression given as its argument. If the expression is false, it should be printed with an appropriate diagnostic.

3. Modify the script implementation on page 175 so that it writes a welcome message (to the log as well) just like the real script command.

4. Your system administrators are paranoid. They are willing to give you the root password only if you send them a log of everything you do while using it. Write a non-setuid script that provides root access and records all of your interactions.