TSPI_phoneGetExtensionID

The TSPI_phoneGetExtensionID function retrieves the extension identifier that the service provider supports for the indicated phone device.

LONG TSPIAPI TSPI_phoneGetExtensionID(
  DWORD dwDeviceID,                 
  DWORD dwTSPIVersion,              
  LPPHONEEXTENSIONID lpExtensionID  
);

Parameters

dwDeviceID

The phone device to be queried.

dwTSPIVersion

Specifies an interface version number that is negotiated for this device using TSPI_phoneNegotiateTSPIVersion. This function operates according to the interface specification at this version level.

lpExtensionID

A pointer to a structure of type PHONEEXTENSIONID. If the service provider supports provider-specific extensions, it fills this structure with the extension identifier of these extensions. If the service provider does not support extensions, it fills this structure with all zeros. An extension identifier of all zeros is not a legal extension identifier, since the all-zeros value is used to indicate that the service provider does not support extensions.

Return Values

Returns zero if the function succeeds, or an error number if an error occurs. Possible return values are as follows:

PHONEERR_INCOMPATIBLEAPIVERSION, PHONEERR_RESOURCEUNAVAIL, PHONEERR_NODRIVER, PHONEERR_OPERATIONFAILED, PHONEERR_NOMEM, PHONEERR_OPERATIONUNAVAIL.

Remarks

This function is typically called by TAPI in response to an application calling the phoneNegotiateAPIVersion function. The result returned by the service provider should be appropriate for use in a subsequent call to TSPI_phoneNegotiateExtVersion.

Requirements

  Windows NT/2000: Requires Windows NT 4.0 SP3 or later.
  Windows 95/98: Requires Windows 95 or later.
  Version: Requires TAPI 2.0 or later.
  Header: Declared in Tspi.h.

See Also

PHONEEXTENSIONID, TSPI_phoneNegotiateExtVersion, TSPI_phoneNegotiateTSPIVersion