OS X's headers split up the current and old (BIND 4) nameserver stuff
slightly differently than Linux does, but explicitly including
arpa/nameser_compat.h does the right thing on both. Part of #580301
GResolver provides asynchronous (and synchronous-but-cancellable) APIs
for resolving hostnames, reverse-resolving IP addresses back to
hostnames, and resolving SRV records. Part of #548466.
Types and methods for dealing with IPv4 and IPv6 addresses (and UNIX
domain socket addresses under UNIX). This does not include code for
actual socket I/O.
Originally from "gnio". Much of the code was written by Christian
Kellner, Samuel Cormier-Iijima, and Ryan Lortie.
Part of #548466.