Pointer to current plug-in instance. Pointer to current stream. Pointer to full path to a local file. If an error occurs while retrieving the data or writing the file, fname may be null.
When the stream is complete, the browser calls NPP_StreamAsFile to provide the instance with a full path name for a local file for the stream. NPP_StreamAsFile is called for streams whose mode is set to NP_ASFILEONLY or NP_ASFILE only in a previous call to NPP_NewStream.