phoneGetGain

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

Note This function is for TAPI version 2.0 and later.

LONG WINAPI phoneGetGain(
  HPHONE hPhone,
  DWORD dwHookSwitchDev,
  LPDWORD lpdwGain 
);

hPhone
Handle to the open phone device.
dwHookSwitchDev
Hookswitch device whose gain level is queried. The dwHookSwitchDev parameter can have only one bit set. This parameter uses one and only one of the PHONEHOOKSWITCHDEV constants.
lpdwGain
Pointer to a DWORD containing the current gain setting of the hookswitch microphone component. The dwGain parameter specifies the volume level of the hookswitch device. This is a number in the range 0x00000000 (silence) to 0x0000FFFF (maximum volume). The actual granularity and quantization of gain settings in this range are service provider-specific.

Returns zero if the request succeeds or a negative error number if an error occurs. The following table shows the return values for this function.

Value	Description
PHONEERR_INVALPHONEHANDLE	The handle to the open phone device is invalid.
PHONEERR_NOMEM	Not enough memory is available.
PHONEERR_INVALPOINTER	The pointer is invalid.
PHONEERR_RESOURCEUNAVAIL	The resources are unavailable.
PHONEERR_INVALPHONESTATE	The phone state is invalid.
PHONEERR_OPERATIONFAILED	The operation failed.
PHONEERR_INVALHOOKSWITCHDEV	The hookswitch device is invalid.
PHONEERR_UNINITIALIZED	A parameter is uninitialized.
PHONEERR_OPERATIONUNAVAIL	The operation is unavailable.

OS Versions: Windows CE 3.0 and later.
Header: Tapi.h.
Link Library: Coredll.lib.

Last updated on Saturday, April 10, 2004

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