WSAEAFNOSUPPORT - Error 10047

Question/Problem: WSAEAFNOSUUPORT (10047) Address family not supported by protocol family.

Answer/Solution: An address incompatible with the requested protocol was used. For example, you shouldn't necessarily expect to be able to use NS addresses with ARPA Internet protocols.

It also occurs with functions that take a socket handle and a sockaddr structure as input parameters. A socket already has a type (a protocol), and each sockaddr structure has an address family field to define its format. A function fails with WSAEAFNOSUPPORT if the address family referenced in sockaddr is not compatible with the referenced socket's protocol.

This error apparently also takes the place of WSAEPFNOSUPPORT (which means "protocol family not supported"), since that error is not listed for socket. in the v1.1 WinSock specification.