WSHGetSockaddrType

INT
WSHGetSockaddrType(
IN PSOCKADDR Sockaddr,
IN DWORD SockaddrLength,
OUT PSOCKADDR_INFO SockaddrInfo
);

WSHGetSockaddrType parses a socket address and returns information about it to Windows Sockets.

Parameters

Sockaddr

Points to the SOCKADDR structure to be evaluated.

SockaddrLength

Specifies the length, in bytes, of the SOCKADDR structure at Sockaddr.

SockaddrInfo

Points to a buffer in which the helper DLL returns information about the socket address, formatted as a SOCKADDR_INFO structure.

Return Value

WSHGetSockaddrType returns zero if the given socket address is valid for the address family supported by this helper DLL. Otherwise, it returns a Windows Sockets error code.

Comments

Windows Sockets calls WSHGetSockaddrType when it needs information about a SOCKADDR. The helper DLL evaluates both the machine address and endpoint portions of the SOCKADDR. The machine-address portion specifies a particular machine, for example, the IP address in an internet address. The endpoint specifies a particular service on a machine, corresponding to the port number in an internet address.

The SOCKADDR_INFO structure is defined as follows:

typedef struct _SOCKADDR_INFO {

SOCKADDR_ADDRESS_INFO AddressInfo;

SOCKADDR_ENDPOINT_INFO EndpointInfo;

} SOCKADDR_INFO, *PSOCKADDR_INFO;

SOCKADDR_ADDRESS_INFO is an enumerated type, with the following possible values:

SockaddrAddressInfoNormal

The address portion of the SOCKADDR has no unusual characteristics.

SockaddrAddressInfoWildcard

The address portion of the SOCKADDR is a "wildcard," meaning that it does not specify a particular address. For example, this corresponds to INADDR_ANY (0.0.0.0) for IP addresses, which an application passes to bind when it has no particular requirements for the IP address used for a socket.

SockaddrAddressInfoBroadcast

The address portion of the SOCKADDR refers to the address family's broadcast address. For example, in IP addresses, this is INADDR_BROADCAST (255.255.255.255).

SockaddrAddressInfoLoopback

The address portion of the SOCKADDR refers to the address family's loopback address. For example, in internet addresses, this is INADDR_LOOPBACK (127.0.0.1).

SOCKADDR_ENDPOINT_INFO also is an enumerated type, with the following possible values:

SockaddrEndpointInfoNormal

The endpoint portion of the SOCKADDR has no unusual characteristics.

SockaddrEndpointInfoWildcard

The endpoint portion of the SOCKADDR is a wildcard, meaning that it could refer to any endpoint. An application, typically a client, can pass a wildcard endpoint to bind when it has no particular requirements for the endpoint assigned. For example, in IP addresses, a port set to zero is a wildcard endpoint.

SockaddrEndpointInfoReserved

The endpoint of the SOCKADDR is reserved, meaning that special privilege is required to bind to it. For example, in internet addresses, a port with a value less than IPPORT_RESERVED (1024) is a reserved endpoint.