+XBT_PUBLIC(void) TRACE_host_state_declare (const char *state);
+XBT_PUBLIC(void) TRACE_host_state_declare_value (const char *state, const char *value, const char *color);
+XBT_PUBLIC(void) TRACE_host_set_state (const char *host, const char *state, const char *value);
+XBT_PUBLIC(void) TRACE_host_push_state (const char *host, const char *state, const char *value);
+XBT_PUBLIC(void) TRACE_host_pop_state (const char *host, const char *state);
+
+/* for creating graph configuration files for Triva by hand */
+XBT_PUBLIC(xbt_dynar_t) TRACE_get_node_types (void);
+XBT_PUBLIC(xbt_dynar_t) TRACE_get_edge_types (void);