NdisMCmDeactivateVc function (ndis.h)

Article
04/18/2022

NdisMCmDeactivateVc notifies NDIS that there will be no further transfers on a particular active VC.

Syntax

NDIS_STATUS NdisMCmDeactivateVc(
  [in] NDIS_HANDLE NdisVcHandle
);

Parameters

[in] NdisVcHandle

Specifies the handle identifying the VC. This handle was supplied by NDIS to the MCM driver either when it called NdisMCmCreateVc for an incoming call or when its ProtocolCoCreateVc function set up the VC for a client-initiated outgoing call.

Return value

NdisMCmDeactivateVc can return one of the following:

Return code	Description
NDIS_STATUS_SUCCESS	NDIS marked the VC as inactive.
NDIS_STATUS_NOT_ACCEPTED	The VC is already deactivated, so this call is redundant.

Remarks

An MCM driver calls NdisMCmDeactivateVc as an essential step in closing a call, usually after the packet exchange with network components that tears down the connection.

A successful call to NdisMCmDeactivateVc allows the MCM driver to discard the current call parameters for transfers on the VC, possibly reinitializing them to miniport driver-determined default values. However, if the VC is reactivated subsequently for another call, the client will supply new call parameters to the miniport driver.

The NdisVcHandle passed to NdisMCmDeactivateVc remains valid after VC deactivation is completed. The deactivation of any VC allows its creator to reinitialize the VC for reuse or to destroy it:

Following VC deactivation and the closing of the call, a client can reuse a VC that it originally created to make another call with NdisClMakeCall, or it can call NdisCoDeleteVc, thereby causing a call to the MCM driver's ProtocolCoDeleteVc function.
Following VC deactivation and the closing of the call, an MCM driver can reuse a VC that it originally created to indicate another incoming call to the same client with NdisMCmDispatchIncomingCall, or it can call NdisMCmDeleteVc.

The driver writer determines whether an MCM driver has an (internal) MiniportCoDeactivateVc function that the driver calls in the context of tearing down connections for outgoing and incoming calls.

Only connection-oriented miniport drivers that provide integrated call-management support can call NdisMCmDeactivateVc. Stand-alone call managers, which register themselves with NDIS as protocol drivers, call NdisCmDeactivateVc instead.

Requirements

Requirement	Value
Minimum supported client	Supported for NDIS 6.0 and NDIS 5.1 drivers (see NdisMCmDeactivateVc (NDIS 5.1)) in Windows Vista. Supported for NDIS 5.1 drivers (see NdisMCmDeactivateVc (NDIS 5.1)) in Windows XP.
Target Platform	Desktop
Header	ndis.h (include Ndis.h)
Library	Ndis.lib
IRQL	<= DISPATCH_LEVEL
DDI compliance rules	Irql_MCM_Function(ndis)