Default DIF code handlers perform system-defined default operations for DIF codes. As described in Handling DIF Codes, SetupDiCallClassInstaller calls the default handler for a DIF request after the class installer and co-installer have first processed the DIF request, but before SetupDiCallClassInstaller recalls the co-installers that registered for post-processing of the request.
Note The operation of SetupDiCallClassInstaller cannot be configured to recall the class installer to post-process a DIF request.
In those situations where a class installer must perform operations for a DIF request after the default handler is called, the class installer must directly call the default handler when it processes the DIF request, as follows:
Perform operations that must be done before calling the default handler.
Call the default handler to perform the default operations.
Note The class installer must not attempt to supersede the operation of the default handler.
Perform the operations that must be done after the default handler returns.
Return NO_ERROR if the class installer successfully completed processing the DIF request or return a Win32 error if the processing failed.
The following table lists the DIF codes that have default handlers.