Description:

A completely new version of 'host', a nameserver query utility a la
'nslookup' and 'dig', but much more versatile and robust.

Among the new features are:
- Extensive error checking.
- Optionally (very) verbose output and debugging info.
- Checking for extraneous conditions during zone listings such as
non-authoritative glue records and lame delegations.
- Checking for illegal characters in certain domain names.
- Verify that some host-related domain names are canonical.
- Perform ttl consistency checking during zone listings.
- Recursive traversion of delegated zones up to a given level.
- Maintaining of resource record and host count statistics.
- Option to check reverse mappings of host addresses.
- Option to compare SOA records at the primary and secondary
nameservers of a zone to check for anomalies such as out-of-sync
serial numbers, and other discrepancies.
- Recognition of the new RR types as defined by RFC 1183/1348.
- Basic NSAP support according to RFC 1637.
- Implement PX/GPOS RR types as defined by RFC 1664/1712.
- Implement LOC RR type as defined by RFC 1876.
- Recognize AAAA RR type as defined by RFC 1884/1886.
- Support for new RR types KEY/SIG/NXT/SRV (still in draft).
- Support for RR type NAPTR. Recognize EID/NIMLOC/ATMA.
- Support for RR type KX. Recognize CERT.
- Allow multiple arguments on command line or from stdin.
- Configurable default options via an environment variable.
- Anticipate non-BIND behaviour during zone listings.

And many more; see the manual page, the RELEASE NOTES, and the
extensively documented code for details.