Creating users from shell or perl script

I have written a program that will install some software,
create a database, and create a couple of postgres users. Most
everything is working, but I cannot see how to create postgres
users with set passwords. If the script calls createuser the
prompts do not come to the user, and anyway I do not want them to.
I want to be able to create the user with a password and not have
the person running the script see it. Right now I am trying in perl:
$output = `/usr/local/pgsql/bin/createuser $New_User ` ;

I have tried attaching using DBI but don't know what DB to attach to.

Any hints or tips appreciated.

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Danny Aldham Providing Certified Internetworking Solutions to Business
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