- incompletely specified ip addresses
- ip addresses specified in hex
like inet_aton() and inet_addr(). This broke parsing of /etc/hosts
(127.1 localhost stopped working before the resolver is started).
The fix is to use the inet_aton() code to implement inet_pton4(), and
then use the new inet_pton4() code to implement inet_aton() and inet_addr().
At that point inet_addr.c is empty and has been removed.