- struct bt_event_class *event_class = NULL, *writer_event_class = NULL;
- struct bt_stream *stream = NULL, *writer_stream = NULL;
- struct bt_stream_class *stream_class = NULL, *writer_stream_class = NULL;
- struct bt_event *writer_event = NULL;
+ const struct bt_event_class *event_class = NULL, *writer_event_class = NULL;
+ const struct bt_stream *stream = NULL, *writer_stream = NULL;
+ const struct bt_stream_class *stream_class = NULL, *writer_stream_class = NULL;
+ const struct bt_event *writer_event = NULL;