NdisClGetProtocolVcContextFromTapiCallId function (ndis.h)

NdisClGetProtocolVcContextFromTapiCallId retrieves the client context for a virtual connection (VC) identified by a TAPI Call ID string.

Syntax

NDIS_STATUS NdisClGetProtocolVcContextFromTapiCallId(
  [in]  UNICODE_STRING TapiCallId,
  [out] PNDIS_HANDLE   ProtocolVcContext
);

Parameters

[in] TapiCallId

Unicode string that identifies a particular VC. This string is the Unicode version of a string identifier that was previously returned by the NdisCoGetTapiCallID function.

[out] ProtocolVcContext

Pointer to a caller-allocated NDIS_HANDLE that receives a handle to the client context for the VC. The client supplied this context to NDIS on return from its ProtocolCoCreateVc handler.

Return value

Returns one of the following status values:

Remarks

Suppose a call manager calls NdisCoCreateVc to create a VC for a TAPI call. NDIS in turn supplies the handle to the VC to a client. The client passes this VC handle in a call to the NdisCoGetTapiCallId function to retrieve a string identifier for the VC. The client can then present this identifier as a Unicode string to NdisClGetProtocolVcContextFromTapiCallId to get back its context for the VC.

The client creates a context for each VC that it manages. The client uses NdisCoGetTapiCallId to retrieve a string identifier for each VC. The client passes each string identifier to a TAPI application to identify each VC. Later, if a TAPI application passes one of these string identifiers down to the client in a VC-related operation, the client must pass this string identifier as a Unicode string in a call to NdisClGetProtocolVcContextFromTapiCallId to get back the correct context for the VC.

See the UNICODE_STRING structure for more information.

Requirements

See also

NdisCoCreateVc

NdisCoGetTapiCallId

UNICODE_STRING