linePrepareAddToConference

The linePrepareAddToConference function prepares an existing conference call for the addition of another party.

LONG WINAPI linePrepareAddToConference(
  HCALL hConfCall,                     
  LPHCALL lphConsultCall,              
  LPLINECALLPARAMS const lpCallParams  
);

Parameters

hConfCall

A handle to a conference call. The application must be an owner of this call. The call state of hConfCall must be connected.

lphConsultCall

A pointer to an HCALL handle. This location is then loaded with a handle identifying the consultation call to be added. Initially, the application is the sole owner of this call.

lpCallParams

A pointer to call parameters to be used when establishing the consultation call. This parameter can be set to NULL if no special call setup parameters are desired.

Return Values

Returns a positive request identifier if the function is completed asynchronously, or a negative error number if an error occurs. The dwParam2 parameter of the corresponding LINE_REPLY message is zero if the function succeeds or it is a negative error number if an error occurs. Possible return values are:

LINEERR_BEARERMODEUNAVAIL, LINEERR_INVALPOINTER, LINEERR_CALLUNAVAIL, LINEERR_INVALRATE, LINEERR_CONFERENCEFULL, LINEERR_NOMEM, LINEERR_INUSE, LINEERR_NOTOWNER, LINEERR_INVALADDRESSMODE, LINEERR_OPERATIONUNAVAIL, LINEERR_INVALBEARERMODE, LINEERR_OPERATIONFAILED, LINEERR_INVALCALLPARAMS, LINEERR_RATEUNAVAIL, LINEERR_INVALCALLSTATE, LINEERR_RESOURCEUNAVAIL, LINEERR_INVALCONFCALLHANDLE, LINEERR_STRUCTURETOOSMALL, LINEERR_INVALLINESTATE, LINEERR_USERUSERINFOTOOBIG, LINEERR_INVALMEDIAMODE, LINEERR_UNINITIALIZED.

Remarks

If LINEERR_INVALLINESTATE is returned, the line is currently not in a state in which this operation can be performed. A list of currently valid operations can be found in the dwLineFeatures member (of the type LINEFEATURE) in the LINEDEVSTATUS structure. (Calling lineGetLineDevStatus updates the information in LINEDEVSTATUS.)

A conference call handle can be obtained with lineSetupConference or with lineCompleteTransfer that is resolved as a three-way conference call. The linePrepareAddToConference function typically places the existing conference call in the onHoldPendingConference state and creates a consultation call that can be added later to the existing conference call with lineAddToConference.

The consultation call can be canceled using lineDrop. It may also be possible for an application to swap between the consultation call and the held conference call with lineSwapHold.

Requirements

  Windows NT/2000: Requires Windows NT 4.0 SP3 or later.
  Windows 95/98: Requires Windows 95 or later.
  Version: Requires TAPI 1.3 or later.
  Header: Declared in Tapi.h.
  Library: Use Tapi32.lib.
  Unicode: Implemented as Unicode and ANSI versions on all platforms.

See Also

Conference Overview, Supplementary Line Service Functions, LINE_REPLY, lineAddToConference, lineCompleteTransfer, LINEDEVSTATUS, lineDrop, lineGetLineDevStatus, lineSetupConference, lineSwapHold