So I was looking through winsock.h and saw this...
/*
* Address families.
*/
#define AF_UNSPEC 0 /* unspecified */
#define AF_UNIX 1 /* local to host (pipes, portals) */
#define AF_INET 2 /* internetwork: UDP, TCP, etc. */
#define AF_IMPLINK 3 /* arpanet imp addresses */
#define AF_PUP 4 /* pup protocols: e.g. BSP */
#define AF_CHAOS 5 /* mit CHAOS protocols */
#define AF_IPX 6 /* IPX and SPX */
#define AF_NS 6 /* XEROX NS protocols */
#define AF_ISO 7 /* ISO protocols */
#define AF_OSI AF_ISO /* OSI is ISO */
#define AF_ECMA 8 /* european computer manufacturers */
#define AF_DATAKIT 9 /* datakit protocols */
#define AF_CCITT 10 /* CCITT protocols, X.25 etc */
#define AF_SNA 11 /* IBM SNA */
#define AF_DECnet 12 /* DECnet */
#define AF_DLI 13 /* Direct data link interface */
#define AF_LAT 14 /* LAT */
#define AF_HYLINK 15 /* NSC Hyperchannel */
#define AF_APPLETALK 16 /* AppleTalk */
#define AF_NETBIOS 17 /* NetBios-style addresses */
#define AF_VOICEVIEW 18 /* VoiceView */
#define AF_FIREFOX 19 /* FireFox */
#define AF_UNKNOWN1 20 /* Somebody is using this! */
#define AF_BAN 21 /* Banyan */
#define AF_MAX 22
Look at #19.
