NotifyStableUnicastIpAddressTable function (netioapi.h)

The NotifyStableUnicastIpAddressTable function retrieves the stable unicast IP address table on a local computer.

Syntax

IPHLPAPI_DLL_LINKAGE _NETIOAPI_SUCCESS_ NETIOAPI_API NotifyStableUnicastIpAddressTable(
  [in]      ADDRESS_FAMILY                           Family,
  [in, out] PMIB_UNICASTIPADDRESS_TABLE              *Table,
  [in]      PSTABLE_UNICAST_IPADDRESS_TABLE_CALLBACK CallerCallback,
  [in]      PVOID                                    CallerContext,
  [in, out] HANDLE                                   *NotificationHandle
);

Parameters

[in] Family

The address family to retrieve.

Possible values for the address family are listed in the Winsock2.h header file. Note that the values for the AF_ address family and PF_ protocol family constants are identical (for example, AF_INET and PF_INET), so either constant can be used.

On the Windows SDK released for Windows Vista and later, the organization of header files has changed and possible values for this member are defined in the Ws2def.h header file. Note that the Ws2def.h header file is automatically included in Winsock2.h, and should never be used directly.

The values currently supported are AF_INET, AF_INET6, and AF_UNSPEC.

Value Meaning
AF_UNSPEC
0
The address family is unspecified. When this parameter is specified, the function retrieves the stable unicast IP address table containing both IPv4 and IPv6 entries.
AF_INET
2
The Internet Protocol version 4 (IPv4) address family. When this parameter is specified, the function retrieves the stable unicast IP address table containing only IPv4 entries.
AF_INET6
23
The Internet Protocol version 6 (IPv6) address family. When this parameter is specified, the function retrieves the stable unicast IP address table containing only IPv6 entries.

[in, out] Table

A pointer to a MIB_UNICASTIPADDRESS_TABLE structure. When NotifyStableUnicastIpAddressTable is successful, this parameter returns the stable unicast IP address table on the local computer.

When NotifyStableUnicastIpAddressTable returns ERROR_IO_PENDING indicating that the I/O request is pending, then the stable unicast IP address table is returned to the function in the CallerCallback parameter.

[in] CallerCallback

A pointer to the function to call with the stable unicast IP address table. This function will be invoked if NotifyStableUnicastIpAddressTable returns ERROR_IO_PENDING, indicating that the I/O request is pending.

[in] CallerContext

A user context passed to the callback function specified in the CallerCallback parameter when the stable unicast IP address table si available.

[in, out] NotificationHandle

A pointer used to return a handle that can be used to cancel the request to retrieve the stable unicast IP address table. This parameter is returned if the return value from NotifyStableUnicastIpAddressTable is ERROR_IO_PENDING indicating that the I/O request is pending.

Return value

If the function succeeds immediately, the return value is NO_ERROR and the stable unicast IP table is returned in the Table parameter.

If the I/O request is pending, the function returns ERROR_IO_PENDING and the function pointed to by the CallerCallback parameter is called when the I/O request has completed with the stable unicast IP address table.

If the function fails, the return value is one of the following error codes.

Return code Description
ERROR_INVALID_HANDLE
An internal error occurred where an invalid handle was encountered.
ERROR_INVALID_PARAMETER
An invalid parameter was passed to the function. This error is returned if the Table parameter was a NULL pointer, the NotificationHandle parameter was a NULL pointer, or the Family parameter was not either AF_INET, AF_INET6, or AF_UNSPEC.
ERROR_NOT_ENOUGH_MEMORY
There was insufficient memory.
Other
Use FormatMessage to obtain the message string for the returned error.

Remarks

The NotifyStableUnicastIpAddressTable function is defined on Windows Vista and later.

If the NotifyStableUnicastIpAddressTable function succeeds immediately, the return value is NO_ERROR and the stable unicast IP table is returned in the Table parameter. The calling application should free the memory pointed to by the Table parameter using the FreeMibTable function when the MIB_UNICASTIPADDRESS_TABLE information is no longer needed.

All unicast IP addresses except dial-on-demand addresses are considered stable only if they are in the preferred state. For a normal unicast IP address entry, this would correspond to a DadState member of the MIB_UNICASTIPADDRESS_ROW for the IP address set to IpDadStatePreferred. Every dial-on-demand address defines its own stability metric. Currently the only dial-on-demand address considered by this function is the unicast IP address used by the Teredo client on the local computer.

The Family parameter must be set to either AF_INET, AF_INET6, or AF_UNSPEC.

When NotifyStableUnicastIpAddressTable is successful and returns NO_ERROR, the Table parameter returns the stable unicast IP address table on the local computer.

When NotifyStableUnicastIpAddressTable returns ERROR_IO_PENDING indicating that the I/O request is pending, then the stable unicast IP address table is returned to the function in the CallerCallback parameter.

The NotifyStableUnicastIpAddressTable function is used primarily by applications that use the Teredo client.

If the unicast IP address used by Teredo is available on the local computer but not in the stable (qualified) state, NotifyStableUnicastIpAddressTable returns ERROR_IO_PENDING and the stable unicast IP address table is eventually returned by calling the function in the CallerCallback parameter. If the Teredo address is not available or is in the stable state and the other unicast IP addresses are in a stable state, then the function in the CallerCallback parameter will never be invoked.

The callback function specified in the CallerCallback parameter should be defined as a function of type VOID. The parameters passed to the callback function include the following:

Parameter Description
IN PVOID CallerContext The CallerContext parameter passed to the NotifyStableUnicastIpAddressTable function when registering for notifications.
IN PMIB_UNICASTIPADDRESS_TABLE AddressTable A pointer to a MIB_UNICASTIPADDRESS_TABLE containing the stable unicast IP address table on the local computer.
 

The callback function specified in the CallerCallback parameter must be implemented in the same process as the application calling the NotifyStableUnicastIpAddressTable function. If the callback function is in a separate DLL, then the DLL should be loaded before calling the NotifyStableUnicastIpAddressTable function to register for change notifications.

The memory pointed to by the AddressTable parameter used in a callback indication is allocated by the operating system. An application that receives a notification should free the memory pointed to by the AddressTable parameter using the FreeMibTable function when the MIB_UNICASTIPADDRESS_TABLE information is no longer needed.

Once the NotifyStableUnicastIpAddressTable function is called to register for change notifications, these notifications will continue to be sent until the application deregisters for change notifications or the application terminates. If the application terminates, the system will automatically deregister any registration for change notifications. It is still recommended that an application explicitly deregister any change notifications before it terminates.

Any registration for change notifications does not persist if the system is shutdown or rebooted.

To deregister for change notifications, call the CancelMibChangeNotify2 function passing the NotificationHandle parameter returned by NotifyStableUnicastIpAddressTable.

An application cannot make a call to the CancelMibChangeNotify2 function from the context of the thread which is currently executing the notification callback function for the same NotificationHandle parameter. Otherwise, the thread executing that callback will result in deadlock. So the CancelMibChangeNotify2 function must not be called directly as part of the notification callback routine. In a more general situation, a thread that executes the CancelMibChangeNotify2 function cannot own a resource on which the thread that executes a notification callback operation would wait because it would result in a similar deadlock. The CancelMibChangeNotify2 function should be called from a different thread, on which the thread that receives the notification callback doesn’t have dependencies on.

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps | UWP apps]
Minimum supported server Windows Server 2008 [desktop apps | UWP apps]
Target Platform Windows
Header netioapi.h (include Iphlpapi.h)
Library Iphlpapi.lib
DLL Iphlpapi.dll

See also

CancelMibChangeNotify2

CreateUnicastIpAddressEntry

DeleteUnicastIpAddressEntry

FreeMibTable

GetTeredoPort

GetUnicastIpAddressEntry

GetUnicastIpAddressTable

IP Helper Function Reference

InitializeUnicastIpAddressEntry

MIB_NOTIFICATION_TYPE

MIB_UNICASTIPADDRESS_ROW

MIB_UNICASTIPADDRESS_TABLE

NotifyTeredoPortChange

NotifyUnicastIpAddressChange

SetUnicastIpAddressEntry