TSPI_phoneGetGain

The TSPI_phoneGetGain function returns the gain setting of the microphone of the specified phone's hookswitch device.

LONG TSPIAPI TSPI_phoneGetGain(
  HDRVPHONE hdPhone,      
  DWORD dwHookSwitchDev,  
  LPDWORD lpdwGain        
);

Parameters

hdPhone

The handle to the phone whose gain is to be retrieved.

dwHookSwitchDev

The hookswitch device whose gain level is queried. This parameter may be one and only one of the PHONEHOOKSWITCHDEV_ Constants.

lpdwGain

A pointer to a DWORD-sized location into which the service provider writes the current gain setting of the hookswitch microphone component. The dwGain gain parameter specifies the volume level of the hookswitch 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.

Return Values

Returns zero if the function succeeds, or 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

PHONECAPS, TSPI_phoneGetDevCaps, TSPI_phoneSetGain