TSPI_lineDrop function (tspi.h)

The TSPI_lineDrop function drops or disconnects the specified call. User-user information can optionally be transmitted as part of the call disconnect. This function can be called by the application at any time. When TSPI_lineDrop returns, the call should be idle.

Syntax

LONG TSPIAPI TSPI_lineDrop(
  DRV_REQUESTID dwRequestID,
  HDRVCALL      hdCall,
  LPCSTR        lpsUserUserInfo,
  DWORD         dwSize
);

Parameters

dwRequestID

The identifier of the asynchronous request.

hdCall

The service provider's handle to the call to be dropped. The call state of hdCall can be any state except idle.

lpsUserUserInfo

This pointer is only valid if dwSize is nonzero. It specifies a pointer to a null-terminated string containing user-user information to be sent to the remote party as part of the call disconnect. This pointer is NULL if no user-user information is to be sent. User-user information is only sent if supported by the underlying network (see LINEDEVCAPS).

dwSize

The size in bytes of the user-user information in lpsUserUserInfo. If lpsUserUserInfo is NULL, dwSize is ignored.

Return value

Returns dwRequestID or an error number if an error occurs. The lResult actual parameter of the corresponding ASYNC_COMPLETION is zero if the function succeeds or an error number if an error occurs. Possible return values are as follows:

LINEERR_INVALCALLHANDLE, LINEERR_OPERATIONFAILED, LINEERR_INVALCALLSTATE, LINEERR_RESOURCEUNAVAIL, LINEERR_NOMEM, LINEERR_USERUSERINFOTOOBIG, LINEERR_OPERATIONUNAVAIL.

Remarks

The service provider returns LINEERR_INVALCALLSTATE if the current state of the call does not allow the call to be dropped.

When invoking TSPI_lineDrop, related calls can sometimes be affected as well. For example, dropping a conference call may drop all individual participating calls. LINE_CALLSTATE messages are sent to TAPI for all calls whose call state is affected. Typically, a dropped call transitions to the idle state. Invoking TSPI_lineDrop on a call in the offering state rejects the call. Not all telephone networks provide this capability.

In situations where the call to be dropped is a consultation call established during transfer or conference call establishment, the original call that was placed in the OnHoldPending state is reconnected to and it typically re-enters the connected call state.

TAPI has the option to send user-user information at the time of the drop. Even if user-user information can be sent, there is no guarantee that the network will deliver this information to the remote party.

Requirements

See also

ASYNC_COMPLETION

LINEDEVCAPS

LINE_CALLSTATE

TSPI_lineGetDevCaps