IP_ADAPTER_INFO (Compact 2013)

10/26/2015

This structure contains information about a particular network adapter on the local device.

Syntax

typedef struct _IP_ADAPTER_INFO {
  struct _IP_ADAPTER_INFO* Next;
  DWORD ComboIndex;
  Char AdapterName[MAX_ADAPTER_NAME_LENGTH + 4];
  char Description[MAX_ADAPTER_DESCRIPTION_LENGTH + 4];
  UINT AddressLength;
  BYTE Address[MAX_ADAPTER_ADDRESS_LENGTH];
  DWORD Index;
  UINT Type;
  UINT DhcpEnabled;
  PIP_ADDR_STRING CurrentIpAddress;
  IP_ADDR_STRING IpAddressList;
  IP_ADDR_STRING GatewayList;
  IP_ADDR_STRING DhcpServer;
  BOOL HaveWins;
  IP_ADDR_STRING PrimaryWinsServer;
  IP_ADDR_STRING SecondaryWinsServer;
  time_t LeaseObtained;
  time_t LeaseExpires;
} IP_ADAPTER_INFO, *PIP_ADAPTER_INFO;

Members

  • Next
    Pointer to the next adapter in the linked list of adapters.
  • ComboIndex
    Reserved.
  • AdapterName
    The name of the adapter.
  • Description
    A description for the adapter.
  • AddressLength
    The length of hardware address for the adapter.
  • Address
    The hardware address for the adapter represented as a BYTE array.
  • Index
    The adapter index.

    The adapter index may change when an adapter is disabled and then enabled, or under other circumstances, and should not be considered persistent.

  • Type
    The adapter type. The type must be one of the following values:

    • MIB_IF_TYPE_OTHER
    • MIB_IF_TYPE_ETHERNET
    • MIB_IF_TYPE_TOKENRING
    • MIB_IF_TYPE_FDDI
    • MIB_IF_TYPE_PPP
    • MIB_IF_TYPE_LOOPBACK
    • MIB_IF_TYPE_SLIP

    These values are defined in the header file IPIfCons.h.

  • DhcpEnabled
    TRUE if dynamic host configuration protocol (DHCP) is enabled for this adapter.
  • CurrentIpAddress
    Reserved.
  • IpAddressList
    The list of IPv4 addresses associated with this adapter represented as a linked list of IP_ADDR_STRING structures. An adapter can have multiple IPv4 addresses assigned to it.
  • GatewayList
    The IPv4 address of the gateway for this adapter represented as a linked list of IP_ADDR_STRING structures. An adapter can have multiple IPv4 gateway addresses assigned to it. This list usually contains a single entry for IPv4 address of the default gateway for this adapter.
  • DhcpServer
    The IPv4 address of the DHCP server for this adapter represented as a linked list of IP_ADDR_STRING structures. This list contains a single entry for the IPv4 address of the DHCP server for this adapter. A value of 255.255.255.255 indicates the DHCP server could not be reached, or is in the process of being reached.

    This member is only valid when the DhcpEnabled member is nonzero.

  • HaveWins
    TRUE if this adapter uses Windows Internet Name Service (WINS).
  • PrimaryWinsServer
    The IPv4 address of the primary WINS server represented as a linked list of IP_ADDR_STRING structures. This list contains a single entry for the IPv4 address of the primary WINS server for this adapter.

    This member is only valid when the HaveWins member is TRUE.

  • SecondaryWinsServer
    The IPv4 address of the secondary WINS server represented as a linked list of IP_ADDR_STRING structures. An adapter can have multiple secondary WINS server addresses assigned to it.

    This member is only valid when the HaveWins member is TRUE.

  • LeaseObtained
    The time when the current DHCP lease was obtained.

    This member is only valid when the DhcpEnabled member is nonzero.

  • LeaseExpires
    The time when the current DHCP lease expires.

    This member is only valid when the DhcpEnabled member is nonzero.

Remarks

The IP_ADAPTER_INFO structure is limited to IPv4 information about a particular network adapter on the local device. The IP_ADAPTER_INFO structure is retrieved by calling the GetAdaptersInfo function.

When you use Visual Studio 2013 or Visual Studio 2015, the time_t datatype defaults to an 8-byte datatype, not the 4-byte datatype used for the LeaseObtained and LeaseExpires members on a 32-bit platform. To correctly use the IP_ADAPTER_INFO structure on a 32-bit platform, define _USE_32BIT_TIME_T (use -D _USE_32BIT_TIME_T as an option, for example) when compiling the application to force the time_t datatype to a 4-byte datatype.

Example Code

This example retrieves the adapter information and prints various properties of each adapter.

Important

For readability, the following code example does not contain security checking or error handling. Do not use the following code in a production environment.

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

#define MALLOC(x) HeapAlloc(GetProcessHeap(), 0, (x))
#define FREE(x) HeapFree(GetProcessHeap(), 0, (x))
/* Note: could also use malloc() and free() */

int __cdecl main()
{

    /* Declare and initialize variables */

// It is possible for an adapter to have multiple
// IPv4 addresses, gateways, and secondary WINS servers
// assigned to the adapter. 
//
// Note that this sample code only prints out the 
// first entry for the IP address/mask, and gateway, and
// the primary and secondary WINS server for each adapter. 

    PIP_ADAPTER_INFO pAdapterInfo;
    PIP_ADAPTER_INFO pAdapter = NULL;
    DWORD dwRetVal = 0;
    UINT i;

/* variables used to print DHCP time info */
    struct tm newtime;
    char buffer[32];
    errno_t error;

    ULONG ulOutBufLen = sizeof (IP_ADAPTER_INFO);
    pAdapterInfo = (IP_ADAPTER_INFO *) MALLOC(sizeof (IP_ADAPTER_INFO));
    if (pAdapterInfo == NULL) {
        printf("Error allocating memory needed to call GetAdaptersinfo\n");
        return 1;
    }
// Make an initial call to GetAdaptersInfo to get
// the necessary size into the ulOutBufLen variable
    if (GetAdaptersInfo(pAdapterInfo, &ulOutBufLen) == ERROR_BUFFER_OVERFLOW) {
        FREE(pAdapterInfo);
        pAdapterInfo = (IP_ADAPTER_INFO *) MALLOC(ulOutBufLen);
        if (pAdapterInfo == NULL) {
            printf("Error allocating memory needed to call GetAdaptersinfo\n");
            return 1;
        }
    }

    if ((dwRetVal = GetAdaptersInfo(pAdapterInfo, &ulOutBufLen)) == NO_ERROR) {
        pAdapter = pAdapterInfo;
        while (pAdapter) {
            printf("\tComboIndex: \t5d\n", pAdapter->ComboIndex);
            printf("\tAdapter Name: \t%s\n", pAdapter->AdapterName);
            printf("\tAdapter Desc: \t%s\n", pAdapter->Description);
            printf("\tAdapter Addr: \t");
            for (i = 0; i < pAdapter->AddressLength; i++) {
                if (i == (pAdapter->AddressLength - 1))
                    printf("%.2X\n", (int) pAdapter->Address[i]);
                else
                    printf("%.2X-", (int) pAdapter->Address[i]);
            }
            printf("\tIndex: \t%d\n", pAdapter->Index);
            printf("\tType: \t");
            switch (pAdapter->Type) {
            case MIB_IF_TYPE_OTHER:
                printf("Other\n");
                break;
            case MIB_IF_TYPE_ETHERNET:
                printf("Ethernet\n");
                break;
            case MIB_IF_TYPE_TOKENRING:
                printf("Token Ring\n");
                break;
            case MIB_IF_TYPE_FDDI:
                printf("FDDI\n");
                break;
            case MIB_IF_TYPE_PPP:
                printf("PPP\n");
                break;
            case MIB_IF_TYPE_LOOPBACK:
                printf("Lookback\n");
                break;
            case MIB_IF_TYPE_SLIP:
                printf("Slip\n");
                break;
            default:
                printf("Unknown type %ld\n", pAdapter->Type);
                break;
            }

            printf("\tIP Address: \t%s\n",
                   pAdapter->IpAddressList.IpAddress.String);
            printf("\tIP Mask: \t%s\n", pAdapter->IpAddressList.IpMask.String);

            printf("\tGateway: \t%s\n", pAdapter->GatewayList.IpAddress.String);
            printf("\t***\n");

            if (pAdapter->DhcpEnabled) {
                printf("\tDHCP Enabled: Yes\n");
                printf("\t  DHCP Server: \t%s\n",
                       pAdapter->DhcpServer.IpAddress.String);

                printf("\t  Lease Obtained: ");
                /* Display local time */
                error = _localtime32_s(&newtime, &pAdapter->LeaseObtained);
                if (error)
                    printf("Invalid Argument to _localtime32_s\n");
                else {
                    // Convert to an ASCII representation 
                    error = asctime_s(buffer, 32, &newtime);
                    if (error)
                        printf("Invalid Argument to asctime_s\n");
                    else
                        /* asctime_s returns the string terminated by \n\0 */
                        printf("%s", buffer);
                }

                printf("\t  Lease Expires:  ");
                error = _localtime32_s(&newtime, &pAdapter->LeaseExpires);
                if (error)
                    printf("Invalid Argument to _localtime32_s\n");
                else {
                    // Convert to an ASCII representation 
                    error = asctime_s(buffer, 32, &newtime);
                    if (error)
                        printf("Invalid Argument to asctime_s\n");
                    else
                        /* asctime_s returns the string terminated by \n\0 */
                        printf("%s", buffer);
                }
            } else
                printf("\tDHCP Enabled: No\n");

            if (pAdapter->HaveWins) {
                printf("\tHave Wins: Yes\n");
                printf("\t  Primary Wins Server:    %s\n",
                       pAdapter->PrimaryWinsServer.IpAddress.String);
                printf("\t  Secondary Wins Server:  %s\n",
                       pAdapter->SecondaryWinsServer.IpAddress.String);
            } else
                printf("\tHave Wins: No\n");
            pAdapter = pAdapter->Next;
            printf("\n");
        }
    } else {
        printf("GetAdaptersInfo failed with error: %d\n", dwRetVal);

    }
    if (pAdapterInfo)
        FREE(pAdapterInfo);

    return 0;
}

Requirements

Header

iptypes.h

See Also

Reference

IP Helper Structures
GetAdaptersAddresses
IP_ADAPTER_ADDRESSES
IP_ADDR_STRING
IP_ADDRESS_STRING