TCI_NOTIFY_HANDLER callback function (traffic.h)

Article
10/13/2021

The ClNotifyHandler function is used by traffic control to notify the client of various traffic control–specific events, including the deletion of flows, changes in filter parameters, or the closing of an interface.

The ClNotifyHandler callback function should be exposed by all clients using traffic control services.

Syntax

TCI_NOTIFY_HANDLER TciNotifyHandler;

void TciNotifyHandler(
  [in] HANDLE ClRegCtx,
  [in] HANDLE ClIfcCtx,
  [in] ULONG Event,
  [in] HANDLE SubCode,
  [in] ULONG BufSize,
  [in] PVOID Buffer
)
{...}

Parameters

[in] ClRegCtx

Client registration context, provided to traffic control by the client with the client's call to the TcRegisterClient function.

[in] ClIfcCtx

Client interface context, provided to traffic control by the client with the client's call to the TcOpenInterface function. Note that during a TC_NOTIFY_IFC_UP event, ClIfcCtx is not available and will be set to NULL.

[in] Event

Describes the notification event. See the Remarks section for a list of notification events.

[in] SubCode

Handle used to further qualify a notification event. See Note below for 64-bit for Windows programming issues.

[in] BufSize

Size of the buffer included with the notification event, in bytes.

[in] Buffer

Buffer containing the detailed event information associated with Event and SubCode.

Return value

None

Remarks

Notification events may require the traffic control client to take particular action or respond appropriately, for example, removing filters or enumerating flows for affected interfaces.

The following table describes the various notification events.

Event	SubCode	Buffer contents	Remarks
TC_NOTIFY_IFC_UP	None	Interface name of the new interface	A new traffic control interface is coming up, and the list of addresses is indicated.
TC_NOTIFY_IFC_CLOSE	Reason for close	Interface name of the closed interface	Indicates an interface that was opened by the client is being closed by the system. Note that the interface and its supported flows and filters are closed by the system upon return from the notification handler. The client does not need to close the interface, delete flows, or delete filters.
TC_NOTIFY_IFC_CHANGE	None	New parameter value	Used to notify clients that have registered for interface change notification through the NotifyChange parameter of the TcQueryInterface function.
TC_NOTIFY_PARAM_CHANGED	Pointer to the GUID for a traffic control parameter queried using the TcQueryInterface function.	New parameter value	This event is notified as a result of a change in a parameter previously queried with the NotifyChange flag set.
TC_NOTIFY_FLOW_CLOSE	ClFlowCtx		Indicates system closure of a client-created flow. The system deletes all associated filters.

Note Use of the ClNotifyHandler function requires administrative privilege.

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	traffic.h