IP_ADAPTER_UNICAST_ADDRESS_LH structure (iptypes.h)
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
Alignment
Length
Type: ULONG
The length, in bytes, of this structure.
Flags
Type: DWORD
A set of flags for this IP address.
The following table shows possible values. These constants are defined in the Iptypes.h header file.
| Value | Meaning |
|---|---|
|
The IP address is legal to appear in DNS. |
|
The IP address is a cluster address and should not be used by most applications. |
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.
Remarks
The IP_ADAPTER_ADDRESSES structure is retrieved by the GetAdaptersAddresses function. The FirstUnicastAddress member of the IP_ADAPTER_ADDRESSES structure 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
| Requirement | Value |
|---|---|
| Minimum supported client | Windows XP [desktop apps only] |
| Minimum supported server | Windows Server 2003 [desktop apps only] |
| Header | iptypes.h (include Iphlpapi.h) |