DhcpRegisterParamChange function (dhcpcsdk.h)

Article
02/22/2024

The DhcpRegisterParamChange function enables clients to register for notification of changes in DHCP configuration parameters.

Syntax

DWORD DhcpRegisterParamChange(
  [in]      DWORD                 Flags,
  [in]      LPVOID                Reserved,
  [in]      LPWSTR                AdapterName,
  [in]      LPDHCPCAPI_CLASSID    ClassId,
  [in]      DHCPCAPI_PARAMS_ARRAY Params,
  [in, out] LPVOID                Handle
);

Parameters

[in] Flags

Reserved. Must be set to DHCPCAPI_REGISTER_HANDLE_EVENT. If it is not set to this flag value, the API call will not be successful.

[in] Reserved

Reserved. Must be set to NULL.

[in] AdapterName

GUID of the adapter for which event notification is being requested. Must be under 256 characters.

[in] ClassId

Reserved. Must be set to NULL.

[in] Params

Parameters for which the client is interested in registering for notification, in the form of a DHCPCAPI_PARAMS_ARRAY structure.

[in, out] Handle

Attributes of Handle are determined by the value of Flags. In version 2 of the DHCP API, Flags must be set to DHCPCAPI_REGISTER_HANDLE_EVENT, and therefore, Handle must be a pointer to a HANDLE variable that will hold the handle to a Windows event that gets signaled when parameters specified in Params change. Note that this HANDLE variable is used in a subsequent call to the DhcpDeRegisterParamChange function to deregister event notifications associated with this particular call to the DhcpRegisterParamChange function.

Return value

Returns ERROR_SUCCESS upon successful completion. Otherwise, returns Windows error codes.

Return code	Description
ERROR_INVALID_PARAMETER	Returned if the AdapterName parameter is over 256 characters long.

Remarks

Version 2 of the DHCP Client API provides only event-based notification. With event-based notification in DHCP, clients enable notification by having Handle point to a variable that, upon successful return, holds the EVENT handles that are signaled whenever changes occur to the parameters requested in Params.

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	dhcpcsdk.h
Library	Dhcpcsvc.lib
DLL	Dhcpcsvc.dll