let tmp_map = tempfile () in
ignore (Sys.command (sprintf "%s %s %s > %s"
gviz_cmd map_flags fname tmp_map));
self#load_map tmp_map;
let tmp_map = tempfile () in
ignore (Sys.command (sprintf "%s %s %s > %s"
gviz_cmd map_flags fname tmp_map));
self#load_map tmp_map;