Added -D'efines'.

<ws2tcpip.h> since IPv6 is no longer optional (was it ever?)

Replace <winsock.h> with <winsock2.h> + <ws2tcpip.h>
(ala libcurl since IPv6 is not optional now).

to do (what I believe is) "right". See docs on:
http://publib.boulder.ibm.com/infocenter/pseries/index.jsp?topic=/com.ibm.aix.doc/libs/commtrf2/getservbyport_r.htm

2 - indented and edited to fit better within 80 columns
3 - fixed possible buffer overflow in the service name lookup function

way of detecting it

Added constants that will be used by ares_getaddrinfo. Made ares_getnameinfo use the reentrant getservbyport (getservbyport_r) if it isavailable to ensure it works properly in a threaded environment

inventing and providing our own. Hopefully this solves a HP-UX 11.00 problem.

when getting the DNS server etc.

  Make UDP sockets non-blocking. I've confirmed that at least on Linux 2.4 a
  read event can come back from poll() on a valid SOCK_DGRAM socket but
  recv(2) will still block. This patch doesn't ignore EAGAIN in
  read_udp_packets(), though maybe it should. (This patch was edited by Daniel
  Stenberg and a new configure test was added (imported from curl's configure)
  to properly detect what non-blocking socket approach to use.)

  I'm not quite sure how this was happening, but I've been seeing PTR queries
  which seem to return empty responses. At least, they were empty when calling
  ares_expand_name() on the record. Here's a patch which guarantees to
  NUL-terminate the expanded name. The old behavior failed to NUL-terminate if
  len was 0, and this was causing strlen() to run past the end of the buffer
  after calling ares_expand_name() and getting ARES_SUCCESS as the return
  value. If q is not greater than *s then it's equal and *s is always
  allocated with at least one byte.

1.3.0