Winsock name resolution APIs use separate cache entries for AF_UNSPEC and AF_INET/AF_INET6 queries

Below are two common scenarios for this issue.


Scenario A:

1 Start Network monitor and monitor DNS traffic.

2 Call getaddrinfo for a name using AF_UNSPEC flags on hints (A pointer to an addrinfo structure)
for the addrinfo Structure, please refer to MSDN document:
http://msdn.microsoft.com/en-us/library/ms737530(v=VS.85).aspx

3 Call getaddrinfo for the same name using AF_INET.

4 Call getaddrinfo for the same name using AF_UNSPEC.


Expected result:

Only the second step should send a query to the wire.


Actual result:

Steps 3 and 4 also send a query to the wire and not use cache.



Scenario B:

1 Call getaddrinfo for a name using AF_UNSPEC on hints.

2 Call DnsQuery with option DNS_QUERY_NO_WIRE_QUERY
(Windows 2000 Server and Windows 2000 Professional: use DNS_QUERY_CACHE_ONLY flag instead.)

Expected result:

DsnQuery can get the record from DNS cache.


Actual result:

DnsQuery fails with DNS_ERROR_RECORD_DOES_NOT_EXIST.