phoneSetGain

  • 项目

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

Note   This function is for TAPI version 2.0 and later.

LONG WINAPI phoneSetGain(
  HPHONE hPhone,
  DWORD dwHookSwitchDev,
  DWORD dwGain 
);

Parameters

  • hPhone
    Handle to the open phone device. The application must be the owner of the phone.
  • dwHookSwitchDev
    Hookswitch device whose microphone's gain is to be set. This parameter uses one and only one of the PHONEHOOKSWITCHDEV constants.
  • dwGain
    Pointer to a DWORD containing the new gain setting of the device. The dwGain parameter specifies the gain 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. A value for dwGain that is out of range is set to the nearest value in the range.

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 PHONE_REPLY message 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
PHONEERR_INVALPHONEHANDLE The handle to the open phone device is invalid.
PHONEERR_NOMEM Not enough memory is available.
PHONEERR_NOTOWNER The application is not the owner of this call.
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.

Requirements

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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