-void_f_void_t STag_graph_fun = nil_function;
-void_f_void_t ETag_graph_fun = nil_function;
-void_f_void_t STag_node_fun = nil_function;
-void_f_void_t ETag_node_fun = nil_function;
-void_f_void_t STag_edge_fun = nil_function;
-void_f_void_t ETag_edge_fun = nil_function;
+void_f_void_t STag_graphxml_graph_fun = nil_function;
+void_f_void_t ETag_graphxml_graph_fun = nil_function;
+void_f_void_t STag_graphxml_node_fun = nil_function;
+void_f_void_t ETag_graphxml_node_fun = nil_function;
+void_f_void_t STag_graphxml_edge_fun = nil_function;
+void_f_void_t ETag_graphxml_edge_fun = nil_function;