typedef struct _WSAPROTOCOL_INFOA {
    DWORD dwServiceFlags1;
    DWORD dwServiceFlags2;
    DWORD dwServiceFlags3;
    DWORD dwServiceFlags4;
    DWORD dwProviderFlags;
    GUID ProviderId;
    DWORD dwCatalogEntryId;
    WSAPROTOCOLCHAIN ProtocolChain;
    int iVersion;
    int iAddressFamily;
    int iMaxSockAddr;
    int iMinSockAddr;
    int iSocketType;
    int iProtocol;
    int iProtocolMaxOffset;
    int iNetworkByteOrder;
    int iSecurityScheme;
    DWORD dwMessageSize;
    DWORD dwProviderReserved;
    CHAR   szProtocol[256];
} WSAPROTOCOL_INFOA, *LPWSAPROTOCOL_INFOA;