gst_pad_set_query_type_function  452 gst/gstghostpad.c   gst_pad_set_query_type_function (pad, gst_proxy_pad_do_query_type);
gst_pad_set_query_type_function 1003 gst/gstpad.h   void			gst_pad_set_query_type_function		(GstPad *pad, GstPadQueryTypeFunction type_func);