[pm-h] converting IP<->hostname and UID<->username

Can anyone suggest modules that can convert IP addresses to and from 
hostnames, and UIDs to and from usernames? I've searched CPAN, but I 
didn't come up with anything.
Or should I just call 'getent'? (That works for UID<->username, but not for 
IP addresses not in the host file...)




--------Brady's First Law of Problem Solving:-------
When confronted by a difficult problem, you can
solve it more easily by reducing it to the question,
"How would the Lone Ranger have handled this?"
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