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4/8/2010

This function opens the specified phone device. A phone device can be opened using either owner privilege or monitor privilege. An application that opens the phone with owner privilege can control the phone's lamps, display, ringer, and hookswitch or hookswitches. An application that opens the phone device with monitor privilege is notified only about events that occur at the phone, such as hookswitch changes or button presses.

Ownership of a phone device is exclusive. In other words, only one application can have a phone device opened with owner privilege at a time. The phone device can, however, be opened multiple times with monitor privilege.

Syntax 

LONG WINAPI phoneOpen(
  HPHONEAPP 
hPhoneApp,
  DWORD 
dwDeviceID,
  LPHPHONE 
lphPhone,
  DWORD 
dwAPIVersion,
  DWORD 
dwExtVersion,
  DWORD_PTR 
dwCallbackInstance,
  DWORD 
dwPrivilege 
);

Parameters

hPhoneApp

Handle to the application's registration with TAPI.

dwDeviceID

Phone device to be opened.

lphPhone

Pointer to an HPHONE handle that identifies the open phone device. Use this handle to identify the device when invoking other phone control functions.

dwAPIVersion

API version number under which the application and Telephony API have agreed to operate. This number is obtained from the phoneNegotiateAPIVersionfunction.

dwExtVersion

Extension version number under which the application and the service provider agree to operate. This number is zero if the application does not use any extensions. This number is obtained from the phoneNegotiateExtVersionfunction.

dwCallbackInstance

User instance data passed back to the application with each message. This parameter is not interpreted by the Telephony API.

dwPrivilege

Privilege requested. This parameter uses one and only one of the PHONEPRIVILEGEconstants.

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_ALLOCATED

The specified resource is already allocated.

PHONEERR_NODRIVER

The driver was not found.

PHONEERR_BADDEVICEID

The device identifier is incorrect.

PHONEERR_NOMEM

Not enough memory is available.

PHONEERR_INCOMPATIBLEAPIVERSION

The API version is incompatible.

PHONEERR_OPERATIONFAILED

The operation failed.

PHONEERR_INCOMPATIBLEEXTVERSION

The extension version is incompatible.

PHONEERR_OPERATIONUNAVAIL

The operation is unavailable.

PHONEERR_INVALAPPHANDLE

The handle to the application's registration with TAPI is invalid.

PHONEERR_RESOURCEUNAVAIL

The resources are unavailable.

PHONEERR_INVALPOINTER

The pointer is invalid.

PHONEERR_UNINITIALIZED

A parameter is unintialized.

PHONEERR_INVALPRIVILEGE

The privilege is invalid.

PHONEERR_INUSE

The phone device is in use.

PHONEERR_REINIT

If TAPI reinitialization has been requested, for example as a result of adding or removing a telephony service provider, then phoneInitializeExor phoneOpenrequests are rejected with this error until the last application shuts down its usage of the API (using phoneShutdown), at which time the new configuration becomes effective and applications are once again permitted to call phoneInitializeEx.

PHONEERR_NODEVICE

The device was not found.

PHONEERR_INIFILECORRUPT

The INI file is corrupted.

Remarks

When opening a phone device with monitor privileges, the application is sent messages when events occur that change the status of the phone. Messages sent to the application include PHONE_BUTTONand PHONE_STATE. The latter provides an indication of the phone's status item that has changed.

When opening a phone with owner privilege, the phone device can be manipulated in ways that affect the state of the phone device. An application should only open a phone using owner privilege if it actively wants to manipulate the phone device, and it should close the phone device when finished to allow other applications to control the phone.

When an application opens a phone device, it must specify the negotiated API version and, if it wants to use the phone's extensions, the phone's device-specific extension version. This version number should have been obtained with the phoneNegotiateAPIVersionand phoneNegotiateExtVersionfunctions. Version numbering allows the mix and match of different application versions with different API versions and service-provider versions.

Note:
This function is for TAPI version 2.0 and later.

Requirements

Header tapi.h
Library coredll.lib
Windows Embedded CE Windows CE 3.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also