nslint -- Checks DNS files for errors<hr>
nslint is a lint-like program that checks DNS files for errors.  DNS or
Domain Name System generally maps names to IP addresses and e-mail
addresses in a hierarchical fashion.

Errors detected include missing trailing dots, illegal characters (RFC
1034), A records without matching PTR records and vice-versa, duplicat
names in a subnet, duplicate names for an address, names with cname
records (RFC 1033) missing quotes, and unknown keywords.
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