GetIpInterfaceTable function (netioapi.h)

The GetIpInterfaceTable function retrieves the IP interface entries on the local computer.

Syntax

IPHLPAPI_DLL_LINKAGE _NETIOAPI_SUCCESS_ NETIOAPI_API GetIpInterfaceTable(
  ADDRESS_FAMILY         Family,
  PMIB_IPINTERFACE_TABLE *Table
);

Parameters

Family

The address family of IP interfaces 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 Windows Vista and later as well as on the Windows SDK, 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 GetIpInterfaceTable function returns the IP interface table containing both IPv4 and IPv6 entries.
AF_INET
2
The Internet Protocol version 4 (IPv4) address family.
AF_INET6
23
The Internet Protocol version 6 (IPv6) address family.

Table

A pointer to a buffer that receives the table of IP interface entries in a MIB_IPINTERFACE_TABLE structure.

Return value

If the function succeeds, the return value is NO_ERROR.

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

Return code Description
ERROR_INVALID_PARAMETER
An invalid parameter was passed to the function. This error is returned if a NULL pointer is passed in the Table parameter or the Family parameter was not specified as AF_INET, AF_INET6, or AF_UNSPEC.
ERROR_NOT_ENOUGH_MEMORY
Insufficient memory resources are available to complete the operation.
ERROR_NOT_FOUND
No IP interface entries as specified in the Family parameter were found.
ERROR_NOT_SUPPORTED
The function is not supported. This error is returned when the IP transport specified in the Address parameter is not configured on the local computer. This error is also returned on versions of Windows where this function is not supported.
Other
Use the FormatMessage function to obtain the message string for the returned error.

Remarks

The GetIpInterfaceTable function is defined on Windows Vista and later.

The
GetIpInterfaceTable function enumerates the IP interfaces on a local system and returns this information in an MIB_IPINTERFACE_TABLE structure.

IP interface entries are returned in a MIB_IPINTERFACE_TABLE structure in the buffer pointed to by the Table parameter. The MIB_IPINTERFACE_TABLE structure contains an IP interface entry count and an array of MIB_IPINTERFACE_ROW structures for each IP interface entry. When these returned structures are no longer required, free the memory by calling the FreeMibTable.

The Family parameter must be initialized to either AF_INET or AF_INET6.

Note that the returned MIB_IPINTERFACE_TABLE structure pointed to by the Table parameter may contain padding for alignment between the NumEntries member and the first MIB_IPINTERFACE_ROW array entry in the Table member of the MIB_IPINTERFACE_TABLE structure. Padding for alignment may also be present between the MIB_IPINTERFACE_ROW array entries. Any access to a MIB_IPINTERFACE_ROW array entry should assume padding may exist.

Examples

The following example retrieves the IP interface table, then prints the values of a few members of the IP interface entries in the table.

#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif

#include <windows.h>
#include <winsock2.h>
#include <ws2ipdef.h>
#include <iphlpapi.h>
#include <stdio.h>
#include <stdlib.h>

#pragma comment(lib, "iphlpapi.lib")

int main()
{
    // Declare and initialize variables

    int i;

    DWORD dwRetVal = 0;

    PMIB_IPINTERFACE_TABLE pipTable = NULL;

    dwRetVal = GetIpInterfaceTable(AF_UNSPEC, &pipTable);
    if (dwRetVal != NO_ERROR) {
        printf("GetIpInterfaceTable returned error: %ld\n", dwRetVal);
        exit(1);
    }
    // Print some variables from the rows in the table
    printf("Number of table entries: %d\n\n", pipTable->NumEntries);

    for (i = 0; i < (int) pipTable->NumEntries; i++) {
        printf("Address Family[%d]:\t\t", i);
        switch (pipTable->Table[i].Family) {
        case AF_INET:
            printf("IPv4\n");
            break;
        case AF_INET6:
            printf("IPv6\n");
            break;
        default:
            printf("Other: %d\n", pipTable->Table[i].Family);
            break;
        }

        printf("Interface LUID NetLuidIndex[%d]:\t %lu\n",
               i, pipTable->Table[i].InterfaceLuid.Info.NetLuidIndex);

        printf("Interface LUID IfType[%d]:\t ", i);
        switch (pipTable->Table[i].InterfaceLuid.Info.IfType) {
        case IF_TYPE_OTHER:
            printf("Other\n");
            break;
        case IF_TYPE_ETHERNET_CSMACD:
            printf("Ethernet\n");
            break;
        case IF_TYPE_ISO88025_TOKENRING:
            printf("Token ring\n");
            break;
        case IF_TYPE_PPP:
            printf("PPP\n");
            break;
        case IF_TYPE_SOFTWARE_LOOPBACK:
            printf("Software loopback\n");
            break;
        case IF_TYPE_ATM:
            printf("ATM\n");
            break;
        case IF_TYPE_IEEE80211:
            printf("802.11 wireless\n");
            break;
        case IF_TYPE_TUNNEL:
            printf("Tunnel encapsulation\n");
            break;
        case IF_TYPE_IEEE1394:
            printf("IEEE 1394 (Firewire)\n");
            break;
        default:
            printf("Unknown: %d\n",
                   pipTable->Table[i].InterfaceLuid.Info.IfType);
            break;
        }
        printf("Interface Index[%d]:\t\t %lu\n",
               i, pipTable->Table[i].InterfaceIndex);
        printf("Maximum reassembly size[%d]:\t %lu\n", i,
               pipTable->Table[i].MaxReassemblySize);

        printf("Advertising enabled[%d]:\t\t ", i);
        if (pipTable->Table[i].AdvertisingEnabled)
            printf("Yes\n");
        else
            printf("No\n");

        printf("Forwarding enabled[%d]:\t\t ", i);
        if (pipTable->Table[i].ForwardingEnabled)
            printf("Yes\n");
        else
            printf("No\n");

        printf("Network layer MTU[%d]:\t\t %lu\n", i, pipTable->Table[i].NlMtu);

        printf("Connected[%d]:\t\t\t ", i);
        if (pipTable->Table[i].Connected)
            printf("Yes\n");
        else
            printf("No\n");

        printf("Supports wakeup patterns[%d]:\t ", i);
        if (pipTable->Table[i].SupportsWakeUpPatterns)
            printf("Yes\n");
        else
            printf("No\n");

        printf("Supports neighbor discovery[%d]:\t ", i);
        if (pipTable->Table[i].SupportsNeighborDiscovery)
            printf("Yes\n");
        else
            printf("No\n");

        printf("Supports router discovery[%d]:\t ", i);
        if (pipTable->Table[i].SupportsRouterDiscovery)
            printf("Yes\n");
        else
            printf("No\n");

        printf("\n");
    }

    FreeMibTable(pipTable);
    pipTable = NULL;

    exit(0);
}


Requirements

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

See also

FreeMibTable

GetIfEntry2

GetIfStackTable

GetIfTable2

GetInvertedIfStackTable

GetIpInterfaceEntry

IP Helper Function Reference

InitializeIpInterfaceEntry

MIB_IF_ROW2

MIB_IF_TABLE2

MIB_IPINTERFACE_ROW

MIB_IPINTERFACE_TABLE

NotifyIpInterfaceChange