Issue1051

It is often needed to build clients/servers that support both IPv4 and IPv6.
Example:
# Echo client program
import socket
import sys
HOST = 'daring.cwi.nl' # The remote host
PORT = 50007 # The same port as used by the server
s = None
for res in socket.getaddrinfo(HOST, PORT, socket.AF_UNSPEC,
socket.SOCK_STREAM):
 af, socktype, proto, canonname, sa = res
 try:
 s = socket.socket(af, socktype, proto)
 except socket.error, msg:
 s = None
 continue
 try:
 s.connect(sa)
 except socket.error, msg:
 s.close()
 s = None
 continue
 break

I noticed that also AI_PASSIVE is not available which is useful to build
IPv4/IPv6 independent servers.

Accepted that this is required for lookups that require both IPV4 and IPV6.
Fixing this bug will require a thorough review of the existing code, for
IPV6 compliance; a review which I will carry out soon.

These constants were added to the socket module in r4948.
More work will be necessary to support IPV6.