phoneNegotiateExtVersion (Compact 2013)

3/26/2014

This function allows an application to negotiate an extension version to use with the specified phone device. This operation need not be called if the application does not support extensions.

Syntax

LONG WINAPI phoneNegotiateExtVersion(
  HPHONEAPP hPhoneApp,
  DWORD dwDeviceID,
  DWORD dwAPIVersion,
  DWORD dwExtLowVersion,
  DWORD dwExtHighVersion,
  LPDWORD lpdwExtVersion 
);

Parameters

• hPhoneApp
  Handle to the application's registration with TAPI.

• dwDeviceID
  Phone device to be queried.

• dwAPIVersion
  API version number that was negotiated for the specified phone device using the phoneNegotiateAPIVersion function.

• dwExtLowVersion
  Least recent extension version of the extension identifier returned by phoneNegotiateAPIVersion that the application is compliant with. The high-order word is the major version number; the low-order word is the minor version number.

• dwExtHighVersion
  Most recent extension version of the extension identifier returned by phoneNegotiateAPIVersion that the application is compliant with. The high-order word is the major version number; the low-order word is the minor version number.

• lpdwExtVersion
  Pointer to a DWORD in which the extension version number that was negotiated is returned. If negotiation succeeds, this number is in the range dwExtLowVersion to dwExtHighVersion.

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.

Remarks

The phoneNegotiateAPIVersion function is used to negotiate the API version number to use. It returns the extension identifier supported by the phone device, or zeros if no extensions are provided.

In order for the application to use the extensions defined by the returned extension identifier, it must call phoneNegotiateExtVersion to negotiate the extension version to use.

Use the phoneInitializeEx function to determine the number of phone devices present in the system. The device identifier specified by dwDeviceID varies from zero to one less than the number of phone devices present.

The extension version number negotiated is that under which the application and service provider must both operate. If version ranges do not overlap, the application and service-provider versions are incompatible and an error is returned.

Requirements

See Also

Reference

TAPI Phone Device Functions
phoneInitializeEx
phoneNegotiateAPIVersion