- If the server returns garbage or nothing at all in response to an AAAA query,
  go on and ask for A records anyway.

  either AF_INET6 or AF_INET. It works by accepting any of the looksups in the
  hosts file, and it resolves the AAAA field with a fallback to A.

  now declares the private struct ares_in6_addr for all systems instead of
  relying on one possibly not present in the system.

  packet storms when several queries were started at the same time.

  that is now used by the ares_parse_*_reply() functions instead of the
  ares_expand_name() simply to easier return ARES_EBADRESP for the cases where
  the name expansion fails as in responses that really isn't expected.

and I edited it to also get duped by ares_dup().

Also discussed on the ml.

buffer to shrink instead of expand if a reply contained 8 or more records.

ares_addr union is now changed into an internal struct which also holds
the address family.

  resolves a host name from the given file, using the regular hosts syntax.

  in man resolv.conf:

  causes round robin selection of nameservers from among those listed.  This
  has the effect of spreading the query load among all listed servers, rather
  than having all clients try the first listed server first every time.

  You can enable it with ARES_OPT_ROTATE

- handles the EINPROGRESS for UDP connects
- uses closesocket instead of close on some paths that were noticed

-s option as well.

  The symptom:
  * Users (usually, but not always) on 2-Wire routers and the Comcast service
  and a wired connection to their router would find that the second and
  subsequent DNS lookups from fresh processes using c-ares to resolve the same
  address would cause the process to never see a reply (it keeps polling for
  around 1m15s before giving up).

  The repro:
  * On such a machine (and yeah, it took us a lot of QA to find the systems
  that reproduce such a specific problem!), do 'ahost www.secondlife.com',
  then do it again.  The first process's lookup will work, subsequent lookups
  will time-out and fail.

  The cause:
  * init_id_key() was calling randomize_key() *before* it initialized
  key->state, meaning that the randomness generated by randomize_key() is
  immediately overwritten with deterministic values. (/dev/urandom was also
  being read incorrectly in the c-ares version we were using, but this was
  fixed in a later version.)
  * This makes the stream of generated query-IDs from any new c-ares process
  be an identical and predictable sequence of IDs.
  * This makes the 2-Wire's default built-in DNS server detect these queries
  as probable-duplicates and (erroneously) not respond at all.

Prior versions of autoconf defined _ALL_SOURCE if _AIX was defined. But,
autoconf 2.62 version of AC_AIX defines _ALL_SOURCE along with other four
preprocessor symbols no matter if the system is AIX or not. To keep the
traditional behaviour, as well as an uniform one, across autoconf versions
AC_AIX is replaced with our own internal macro.

now cause the definition of RECVFROM_TYPE_ARG2_IS_VOID, RECVFROM_TYPE_ARG5_IS_VOID
or RECVFROM_TYPE_ARG6_IS_VOID, as appropriate.

to the data type pointed by its respective argument and not the pointer type.

finds out its return type and the types of its arguments. Added definitions
for non-configure systems config files, and introduced macro sreadfrom which
will be used on udp sockets as a recvfrom() wrapper.

Configure process no longer needs nor checks size of curl_off_t.
Library will now be built with _REENTRANT symbol defined.

  the target host has only A records, it automatically falls back to an
  AF_INET lookup and gives you the A results.  However, if the target host has
  a CNAME record, this behaviour is defeated since the original query does
  return some data even though ares_parse_aaa_reply() doesn't consider it
  relevant. Here's a small patch to make it behave the same with and without
  the CNAME.

  not posix or anything and thus c-ares failed to build on hurd (and possibly
  elsewhere). The define was also somewhat artificially used in the windows
  port. Now, I instead rewrote the use of gethostbyname to enlarge the host
  name buffer in case of need and totally avoid the use of the MAXHOSTNAMELEN
  define. I thus also removed the defien from the namser.h file where it was
  once added for the windows build.

  I also fixed init_by_defaults() function to not leak memory in case if
  error.

  ares_init_options()'s ARES_OPT_TIMEOUTMS.

  lookups. It is not common practice to have multiple PTR-Records for a single
  IP, but its perfectly legal and some sites have those.

  autoconf 2.57 usage (which is the version you have specified as the minimum
  version). It's a minor change but it does clean up some warnings with newer
  autoconf (specifically 2.62).