Platform SDK: TAPI

phoneSetHookSwitch

The phoneSetHookSwitch function sets the hook state of the specified open phone's hookswitch devices to the specified mode. Only the hookswitch state of the hookswitch devices listed is affected.

LONG WINAPI phoneSetHookSwitch(
  HPHONE hPhone,          
  DWORD dwHookSwitchDevs,  
  DWORD dwHookSwitchMode  
);

Parameters

hPhone
A handle to the open phone device. The application must be the owner of the phone.
dwHookSwitchDevs
The device or devices whose hookswitch mode is to be set. This parameter uses one and only one of the PHONEHOOKSWITCHDEV_ Constants.
PHONEHOOKSWITCHDEV_HANDSET
The phone's handset.
PHONEHOOKSWITCHDEV_SPEAKER
The phone's speakerphone or adjunct.
PHONEHOOKSWITCHDEV_HEADSET
The phone's headset.
dwHookSwitchMode
The hookswitch mode to set. This parameter uses one and only one of the PHONEHOOKSWITCHMODE_ Constants.
PHONEHOOKSWITCHMODE_ONHOOK
The device's microphone and speaker are both onhook.
PHONEHOOKSWITCHMODE_MIC
The device's microphone is active, the speaker is mute.
PHONEHOOKSWITCHMODE_SPEAKER
The device's speaker is active, the microphone is mute.
PHONEHOOKSWITCHMODE_MICSPEAKER
The device's microphone and speaker are both active.

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. Possible return values are:

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

Remarks

The hookswitch mode is the same for all specified devices. If different settings are desired, this function can be invoked multiple times with a different set of parameters. A PHONE_STATE message is sent to the application after the hookswitch state has changed.

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 Tapi.h.
  Library: Use Tapi32.lib.

See Also

TAPI 2.2 Reference Overview, Supplementary Phone Service Functions, PHONE_REPLY, PHONE_STATE