how does arguments pass into event_probe_cb and pad_probe_cb?

[Anton Olegovich]

Hi
I can't exectly to understand how does arguments pass into 
event_probe_cb and pad_probe_cb if they are calling by gst_pad_add_probe?
To make my question more precise: are the argumets of gst_pad_add_probe 
(srcpad, GST_PAD_PROBE_TYPE_BLOCK |
GST_PAD_PROBE_TYPE_EVENT_DOWNSTREAM, event_probe_cb, user_data, NULL) 
relative to arguments of event_probe_cb and pad_probe_cb ?