[ Thanks to Noel
for this link. ]
“Shell scripting is a very common tool used for a system
administrator. Automating every task we can is one of the things
that sets us apart as Unix System Admins. It allows us the time to
work on the important things without staying bogged down in the
minutia of running a system. In this article I will introduce you
the very powerful though unusual scripting language Expect….”
“The part you should pay attention to is “Expect really makes
this stuff trivial.” Expect is an easy way to automate those
tasks you end up doing again and again because they span different
machines or because it requires more interaction than you can get
easily from a bash/c/korn shell script. It was written by John
Ousterhout and compiles on most if not all Unix machines.”
“Expect is based on tcl, but is very usable without knowing
hardly anything about tcl. Tool Command Language (TCL) was written
as a standard scripting language to be included with utilities so
people would not have to hack together their own languages. As for
myself I have always been amazed that tcl could come out of the
mind of a c programmer and have been glad that I could use expect
without becoming a tcl expert.”