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phoneGetGain (Compact 2013)

3/26/2014

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

Syntax

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

Parameters

  • 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.

Return Value

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.

Requirements

Header

tapi.h

Library

TAPI32.dll

See Also

Reference

TAPI Phone Device Functions