Platform SDK: TAPI

TSPI_phoneSetGain

The TSPI_phoneSetGain function sets the gain of the microphone of the specified hookswitch device to the specified gain level.

LONG TSPIAPI TSPI_phoneSetGain(
  DRV_REQUESTID dwRequestID,  
  HDRVPHONE hdPhone,      
  DWORD dwHookSwitchDev,  
  DWORD dwGain            
);

Parameters

dwRequestID
The identifier of the asynchronous request.
hdPhone
The handle to the phone containing the hookswitch device whose gain is to be set.
dwHookSwitchDev
The hookswitch device whose microphone's gain is to be set. This parameter uses one and only one of the PHONEHOOKSWITCHDEV_ Constants.
dwGain
A DWORD-sized location containing the desired new gain setting of the device. This is a number in the range from 0x00000000 (silence) through 0x0000FFFF (maximum volume). The actual granularity and quantization of gain settings in this range are service-provider-specific. A value for dwGain that is out of range is clamped by TAPI to the nearest in-range value.

Return Values

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 it is an error number if an error occurs. Possible return values are as follows:

PHONEERR_INVALPHONEHANDLE, PHONEERR_RESOURCEUNAVAIL, PHONEERR_INVALPHONESTATE, PHONEERR_OPERATIONFAILED, PHONEERR_INVALHOOKSWITCHDEV, PHONEERR_OPERATIONUNAVAIL, PHONEERR_NOMEM.

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 Tspi.h.

See Also

ASYNC_COMPLETION, PHONECAPS, TSPI_phoneGetDevCaps, TSPI_phoneSetGain