-- mod.sources, 4.3bsd, 1/86
Improved alias treatment.
Routes to domain gateways.
New domain treatment -- leading dot in name implies domain.
Print fully qualified domain name for private hosts.
Link/host tracing (-t option).
Use getopt().

-- mod.sources, 8/85
Private hosts documented.
Homegrown scanner -- it's true what they say about lex.
Makedb.
Domains and gateways.
DEAD back link.

-- net.sources, 1/85
No ! in dbm key.
Network character must be one of !@%: -- dot is dead.
Private hosts.
Discourage hybrid addresses.  
Magic @ <-> % rule.

-- 1983-1984
Reverse sense of the -c (cost) flag.
Use cheapest among duplicate links.
Elide network names in output.

-- epoch (smb version)