phoneSetVolume function (tapi.h)

The phoneSetVolume function sets the volume of the speaker component of the specified hookswitch device to the specified level.

Syntax

LONG phoneSetVolume(
  HPHONE hPhone,
  DWORD  dwHookSwitchDev,
  DWORD  dwVolume
);

Parameters

hPhone

Handle to the open phone device. The application must be the owner of the phone.

dwHookSwitchDev

Hookswitch device whose speaker's volume is to be set, one of the PHONEHOOKSWITCHDEV_ Constants.

dwVolume

New volume setting of the device. The dwVolume 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 volume settings in this range are service provider-specific. A value for dwVolume that is out of range is set to the nearest value in the range.

Return value

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. Possible return values are:

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

Requirements

See also

PHONE_REPLY

Supplementary Phone Service Functions

TAPI 2.2 Reference Overview