_IP_ADAPTER_UNICAST_ADDRESS_LH structure

The IP_ADAPTER_UNICAST_ADDRESS structure stores a single unicast IP address in a linked list of IP addresses for a particular adapter.

Syntax

typedef struct _IP_ADAPTER_UNICAST_ADDRESS_LH {
  union {
    ULONGLONG Alignment;
    struct {
      ULONG Length;
      DWORD Flags;
    };
  };
  struct _IP_ADAPTER_UNICAST_ADDRESS_LH *Next;
  SOCKET_ADDRESS                        Address;
  IP_PREFIX_ORIGIN                      PrefixOrigin;
  IP_SUFFIX_ORIGIN                      SuffixOrigin;
  IP_DAD_STATE                          DadState;
  ULONG                                 ValidLifetime;
  ULONG                                 PreferredLifetime;
  ULONG                                 LeaseLifetime;
  UINT8                                 OnLinkPrefixLength;
} IP_ADAPTER_UNICAST_ADDRESS_LH, *PIP_ADAPTER_UNICAST_ADDRESS_LH;

Members

__unnamed_union_02fd_2

__unnamed_union_02fd_2.Alignment

__unnamed_union_02fd_2.__unnamed_struct_0

__unnamed_union_02fd_2.__unnamed_struct_0.Length

__unnamed_union_02fd_2.__unnamed_struct_0.Flags

Next

Type: struct _IP_ADAPTER_UNICAST_ADDRESS*

A pointer to the next IP adapter address structure in the list.

Address

Type: SOCKET_ADDRESS

The IP address for this unicast IP address entry. This member can be an IPv6 address or an IPv4 address.

PrefixOrigin

Type: IP_PREFIX_ORIGIN

The prefix or network part of IP the address. This member can be one of the values from the IP_PREFIX_ORIGIN enumeration type defined in the Iptypes.h header file.

SuffixOrigin

Type: IP_SUFFIX_ORIGIN

The suffix or host part of the IP address. This member can be one of the values from the IP_SUFFIX_ORIGIN enumeration type defined in the Iptypes.h header file.

DadState

Type: IP_DAD_STATE

The duplicate address detection (DAD) state. This member can be one of the values from the IP_DAD_STATE enumeration type defined in the Iptypes.h header file. Duplicate address detection is available for both IPv4 and IPv6 addresses.

ValidLifetime

Type: ULONG

The maximum lifetime, in seconds, that the IP address is valid. A value of 0xffffffff is considered to be infinite.

PreferredLifetime

Type: ULONG

The preferred lifetime, in seconds, that the IP address is valid. A value of 0xffffffff is considered to be infinite.

LeaseLifetime

Type: ULONG

The lease lifetime, in seconds, that the IP address is valid.

OnLinkPrefixLength

Type: UINT8

The length, in bits, of the prefix or network part of the IP address. For a unicast IPv4 address, any value greater than 32 is an illegal value. For a unicast IPv6 address, any value greater than 128 is an illegal value. A value of 255 is commonly used to represent an illegal value.

Note  This structure member is only available on Windows Vista and later.
 

Remarks

The IP_ADAPTER_ADDRESSES structure is retrieved by the GetAdaptersAddresses function. The FirstUnicastAddress member of the IP_ADAPTER_ADDRESSESstructure is a pointer to a linked list of IP_ADAPTER_UNICAST_ADDRESS structures.

The size of the IP_ADAPTER_UNICAST_ADDRESS structure changed on Windows Vista and later. The Length member should be used to determine which version of the IP_ADAPTER_UNICAST_ADDRESS structure is being used.

The version of the IP_ADAPTER_UNICAST_ADDRESS structure on Windows Vista and later has the following new member added: OnLinkPrefixLength.

When this structure is used with the GetAdaptersAddresses function and similar management functions, all configured addresses are shown, including duplicate addresses. Such duplicate address entries can occur when addresses are configured statically. Such reporting facilitates administrator troubleshooting. The DadState member is effective in identifying and troubleshooting such situations.

In the Windows SDK, the version of the structure for use on Windows Vista and later is defined as IP_ADAPTER_UNICAST_ADDRESS_LH. In the Windows SDK, the version of this structure to be used on earlier systems including Windows XP with Service Pack 1 (SP1) and later is defined as IP_ADAPTER_UNICAST_ADDRESS_XP. When compiling an application if the target platform is Windows Vista and later (NTDDI_VERSION >= NTDDI_VISTA, _WIN32_WINNT >= 0x0600, or WINVER >= 0x0600), the IP_ADAPTER_UNICAST_ADDRESS_LH structure is typedefed to the IP_ADAPTER_UNICAST_ADDRESS structure. When compiling an application if the target platform is not Windows Vista and later, the IP_ADAPTER_UNICAST_ADDRESS_XP structure is typedefed to the IP_ADAPTER_UNICAST_ADDRESS structure.

The SOCKET_ADDRESS structure is used in the IP_ADAPTER_UNICAST_ADDRESS structure. On the Microsoft Windows Software Development Kit (SDK) released for Windows Vista and later, the organization of header files has changed and the SOCKET_ADDRESS structure is defined in the Ws2def.h header file which is automatically included by the Winsock2.h header file. On the Platform Software Development Kit (SDK) released for Windows Server 2003 and Windows XP, the SOCKET_ADDRESS structure is declared in the Winsock2.h header file. In order to use the IP_ADAPTER_UNICAST_ADDRESS structure, the Winsock2.h header file must be included before the Iphlpapi.h header file.

Requirements

   
Windows version Windows XP [desktop apps only] Windows Server 2003 [desktop apps only]
Header iptypes.h (include Iphlpapi.h)

See Also

GetAdaptersAddresses

IP Helper Start Page

IP Helper Structures

IP_ADAPTER_ADDRESSES

IP_DAD_STATE

IP_PREFIX_ORIGIN

IP_SUFFIX_ORIGIN

SOCKET_ADDRESS