I need a simply way to return the hostname associated with an IP.

$ host yahoo.com
yahoo.com has address 66.94.234.13
[ SNIP ]

$ perl -MSocket -le'my $name = gethostbyaddr inet_aton( "66.94.234.13"
+ ), AF_INET; print $name'
w2.rc.vip.scd.yahoo.com
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