For really sensitive scripts, IMHO your best bet as the script author is: *always* ask for the password. No config files, no commandline parameters, no environment variables.

In a really sensitive environment, someday somebody *will* try it. If he succeeds because your code was careless, people will be angry at you. And they will be right.

With tools like Expect running around for free, your users can always automate interaction with your script, even if it gets complicated and the simple solution jepri gave won't work anymore.

Just make it the user's choice/responsibility.

Christian Lemburg
Brainbench MVP for Perl
http://www.brainbench.com