Managing Network Adapters
A version of this page is also available for
4/8/2010
IP Helper provides capabilities for managing network adapters. The functions described following are used to retrieve information about the network adapters in the local computer.
Interfaces are related to adapters in that there is a one-to-one correspondence between the interfaces and adapters on a given computer. An interface is an IP-level abstraction, whereas an adapter is a datalink-level abstraction.
The GetAdaptersInfo function returns an array of IP_ADAPTER_INFO structures, one for each adapter in the local computer. The GetPerAdapterInfo function returns additional information about a specific adapter. The GetPerAdapterInfo function requires the caller to specify the index of the adapter. To obtain the adapter index from the adapter name, use the GetAdapterIndex function.
The following table describes each GetAdaptersInfo variable and IP_ADAPTER_INFO member.
| Value | Description |
|---|---|
pAdapterInfo |
(Read-only) Pointer to a buffer that, on successful return, receives a linked list of IP_ADAPTER_INFO structures. |
pOutBufLen |
(Read-only) Pointer to a ULONG variable that contains the size of the buffer pointed to by the pAdapterInfo parameter. If this size is insufficient to hold the adapter information, GetAdaptersInfo fills this variable with the required size, and returns an error code of ERROR_BUFFER_OVERFLOW. |
IP_ADAPTER_INFO (All fields are read-only, they cannot be changed by the API user.) |
Next Pointer to the next adapter in the linked list of adapters. ComboIndex This member is unused. AdapterName[MAX_ADAPTER_NAME_LENGTH + 4] Specifies the name of the adapter. Description[MAX_ADAPTER_DESCRIPTION_LENGTH + 4] Specifies a description for the adapter. AddressLength Specifies the length of hardware address for the adapter. Address[MAX_ADAPTER_ADDRESS_LENGTH] Specifies the hardware address for the adapter. Index Specifies the adapter index. Type Specifies the adapter type. DhcpEnabled Specifies whether dynamic host configuration protocol (DHCP) is enabled for this adapter. CurrentIpAddress Specifies the current IP address for this adapter. In Windows Embedded CE, the CurrentIpAddress value is defined as the first address assigned to the specified adapter. IpAddressList Specifies the list of IP addresses associated with this adapter. GatewayList Specifies the IP address of the default gateway for this adapter. DhcpServer Specifies the IP address of the DHCP server for this adapter. HaveWins Specifies whether this adapter uses Windows Internet Name Service (WINS). PrimaryWinsServer Specifies the IP address of the primary WINS server. SecondaryWinsServer Specifies the IP address of the secondary WINS server. LeaseObtained Specifies the time when the current DHCP lease was obtained. LeaseExpires Specifies the time when the current DHCP lease will expire. |
The following table describes each GetPerAdapterInfo variable and IP_PER_ADAPTER_INFO member.
| Value | Description |
|---|---|
IfIndex |
Specifies the index of an interface. GetPerAdapterInfo will retrieve information for the adapter corresponding to this interface. |
pPerAdapterInfo |
Pointer to an IP_PER_ADAPTER_INFO structure that, on successful return, contains information about the adapter. |
pOutBufLen |
Pointer to a ULONG variable that specifies the size of the IP_PER_ADAPTER_INFO structure. If this size is insufficient to hold the information, GetPerAdapterInfo fills in this variable with the required size, and returns an error code of ERROR_BUFFER_OVERFLOW. |
IP_PER_ADAPTER_INFO (All fields are read-only, they cannot be changed by the API user.) |
AutoconfigEnabled Specifies whether auto-configuration is enabled on this adapter. AutoconfigActive Specifies whether auto-configuration is active on this adapter. CurrentDnsServer Not used. DnsServerList Specifies the list of possible DNS servers for this adapter. |
The following table describes each GetAdapterIndex variable.
| Value | Description |
|---|---|
AdapterName |
Pointer to a Unicode string that contains the name of the adapter. |
IfIndex |
Pointer to a ULONG variable that, on successful return, points to the index of the adapter. |