These are options needed for real-world multicasting.
Implementation notes:
- POSIX only.
- IPv4 only (IPv6 multicast is a tricky beast).
- Didn't update tests, because it can't effectively be demonstrated on
localhost only.
- [lib/dns.js] dns.lookup takes a new optional argument "family" which
should be the integer 4, 6, dns.AF_INET or dns.AF_INET6. Passing a
non-false "family" argument makes c-ares explicitly look up addresses for
the specified family.
- [test/simple/test-c-ares.js] test explicit address family lookups
- Adds new dgram module, for all data-gram type transports
- Supports both UDP client and servers
- Supports Unix Daemon sockets in DGRAM mode too (think syslog)
- Uses a shared Buffer and slices that as needed to be reasonably
performant.
- One supplied test program so far, test-dgram-pingpong
- Passes test cases on osx 10.6 and ubuntu 9.10u
