Shell Programming and Scripting

If you have the second user's password then you could write an expect script, but I wouldn't recommend it since you would have to hardcode their password in the script. It might look something like this:

Code:

#!/usr/local/bin/expect

set userpass "their_password"

send "su - login_name"
expect "Password:"
send "$userpass\r"
send "command1\n"
send "command2\n"
send "exit\r"
expect eof

Redirections aren't supposed to work with su. It will try and skip straight to a terminal device to prevent people trying shenanigans. Something more sophisticated like expect is needed to fool it.

And fooling it it is, since it's demanding interactive authentication for a reason. An expect script to cram a keyboard-authenticated password into a shell script is a very bad idea, anyone who sees the script will have the password. If you need permissions you haven't got, you should contact your sysadmin and get them.