+ ep->event_num = index_in_block;
+
+}
+
+/*****************************************************************************
+ * Function name
+ * ltt_event_position_compare : compare two positions
+ * A NULL value is infinite.
+ * Input params
+ * ep1 : a pointer to event's position structure
+ * ep2 : a pointer to event's position structure
+ * Return
+ * -1 is ep1 < ep2
+ * 1 if ep1 > ep2
+ * 0 if ep1 == ep2
+ ****************************************************************************/
+
+
+gint ltt_event_position_compare(const LttEventPosition *ep1,
+ const LttEventPosition *ep2)
+{
+ if(ep1->tf != ep2->tf)
+ g_error("ltt_event_position_compare on different tracefiles makes no sense");
+ if(ep1 == NULL && ep2 == NULL)
+ return 0;
+ if(ep1 != NULL && ep2 == NULL)
+ return -1;
+ if(ep1 == NULL && ep2 != NULL)
+ return 1;
+
+ if(ep1->block_num < ep2->block_num)
+ return -1;
+ if(ep1->block_num > ep2->block_num)
+ return 1;
+ if(ep1->event_num < ep2->event_num)
+ return -1;
+ if(ep1->event_num > ep2->event_num)
+ return 1;
+ return 0;
+}
+
+/*****************************************************************************
+ * Function name
+ * ltt_event_event_position_compare : compare two positions, one in event,
+ * other in position opaque structure.
+ * Input params
+ * event : a pointer to event structure
+ * ep : a pointer to event's position structure
+ * Return
+ * -1 is event < ep
+ * 1 if event > ep
+ * 0 if event == ep
+ ****************************************************************************/
+
+gint ltt_event_event_position_compare(const LttEvent *event,
+ const LttEventPosition *ep)
+{
+ if(event == NULL && ep == NULL)
+ return 0;
+ if(event != NULL && ep == NULL)
+ return -1;
+ if(event == NULL && ep != NULL)
+ return 1;
+
+ g_assert(event->tracefile == ep->tf);
+
+ if(event->which_block < ep->block_num)
+ return -1;
+ if(event->which_block > ep->block_num)
+ return 1;
+ if(event->which_event < ep->event_num)
+ return -1;
+ if(event->which_event > ep->event_num)
+ return 1;
+ return 0;
+}
+
+/*****************************************************************************
+ * Function name
+ * ltt_event_position_copy : copy position
+ * Input params
+ * src : a pointer to event's position structure source
+ * dest : a pointer to event's position structure dest
+ * Return
+ * void
+ ****************************************************************************/
+void ltt_event_position_copy(LttEventPosition *dest,
+ const LttEventPosition *src)
+{
+ if(src == NULL)
+ dest = NULL;
+ else
+ *dest = *src;