an Expect script to do a remote-host 'ls' listing.
FROM: http://www.wellho.net/forum/The-Tcl-programming-language/What-is-Expect-a-sample.html
(imaged on 2009 mar 19)

Posted by admin (Graham Ellis), 7 October 2002.

Expect is an extension to Tcl which allows you to automate
processes such as telnet and FTP by "mimicing" the user's input
in a terminal window.  You use the spawn command to spawn a telnet
(or FTP, or whatever) process, you use send (or exp_send if you're
also using Tk) to send some text as if it was typed, and then you
wait for a specific input pattern to come back via the expect command.

Here's an example that does a remote ls listing;
enter host computer name into an entry box, click on the "go" button,
and you get a listing of all files in the trainee home directory on that system.

Code:


#!/usr/bin/expectk

proc getfiles {host} {
       spawn telnet
       log_user 0
       expect "telnet>"
       exp_send "open $host\r"
       expect {
               "login: " { }
               "Unable" {return "ERROR"}
               }
       exp_send "trainee\r"
       expect "sword: "
       exp_send "abc123\r"
       expect "\$ "
       exp_send "ls -1\r"
       expect "\$ "
       set got $expect_out(buffer)
       exp_send "exit"
       return $got
       }

set hostname "computer name"
entry .host -textvariable hostname

button .do -text go -command {
       set there [getfiles $hostname]
       .what delete 1.0 end
       .what insert end $there
       }

text .what -width 30 -height 40
pack .host .do .what