void xbt_graph_export_graphviz(xbt_graph_t g, const char *filename,
const char *(node_name)(xbt_node_t),
const char *(edge_name)(xbt_edge_t));
void xbt_graph_export_graphxml(xbt_graph_t g, const char *filename,
const char *(node_name)(xbt_node_t),
void xbt_graph_export_graphviz(xbt_graph_t g, const char *filename,
const char *(node_name)(xbt_node_t),
const char *(edge_name)(xbt_edge_t));
void xbt_graph_export_graphxml(xbt_graph_t g, const char *filename,
const char *(node_name)(xbt_node_t),