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4/8/2010

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

Syntax 

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

Parameters

hConfCall

Handle to a conference call. The application must be an owner of this call. The call state of hConfCallmust be connected.

lphConsultCall

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

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 Value

Returns a positive request identifier if the function is completed asynchronously, or a negative error number if an error occurs. The dwParam2parameter of the corresponding LINE_REPLYmessage is zero if the function succeeds or it is a negative error number if an error occurs. The following table shows the return values for this function.

Value Description

LINEERR_BEARERMODEUNAVAIL

The bearer mode member in LINECALLPARAMSis invalid, the bearer mode specified in LINECALLPARAMSis not available, or the call's bearer mode cannot be changed to the specified bearer mode.

LINEERR_INVALPOINTER

The pointer is invalid.

LINEERR_CALLUNAVAIL

The call is unavailable.

LINEERR_INVALRATE

The specified rate is invalid.

LINEERR_CONFERENCEFULL

The conference is full.

LINEERR_NOMEM

Not enough memory is available.

LINEERR_NOTOWNER

The application is not the owner of this call.

LINEERR_INUSE

The line is currently in use.

LINEERR_INVALADDRESSMODE

The address mode is invalid.

LINEERR_OPERATIONUNAVAIL

The operation is unavailable.

LINEERR_INVALBEARERMODE

The bearer mode is invalid.

LINEERR_OPERATIONFAILED

The operation failed.

LINEERR_INVALCALLPARAMS

The call parameters are invalid.

LINEERR_RATEUNAVAIL

The service provider currently does not have enough bandwidth available for the specified rate.

LINEERR_INVALCALLSTATE

The call state is something other than connected.

LINEERR_RESOURCEUNAVAIL

The resources are unavailable.

LINEERR_INVALCONFCALLHANDLE

The handle to the conference call is invalid.

LINEERR_STRUCTURETOOSMALL

The structure is too small.

LINEERR_INVALLINESTATE

The line state is invalid.

LINEERR_USERUSERINFOTOOBIG

The user-user information is too big.

LINEERR_INVALMEDIAMODE

The media mode is invalid.

LINEERR_UNINITIALIZED

A parameter is 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 dwLineFeaturesmember (of the type LINEFEATURE) in the LINEDEVSTATUSstructure. (Calling lineGetLineDevStatusupdates the information in LINEDEVSTATUS.)

A conference call handle can be obtained with the lineSetupConferencefunction or with lineCompleteTransferthat is resolved as a three-way conference call. The linePrepareAddToConferencefunction 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 the lineAddToConferencefunction.

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

Note:
This function is for TAPI version 2.0 and later.

Requirements

Header tapi.h
Library coredll.lib
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also