diff -r d28dff7ac48d -r a4acf1b4d5a8 src/Pure/Thy/thm_deps.ML
--- a/src/Pure/Thy/thm_deps.ML	Wed Oct 13 19:41:18 1999 +0200
+++ b/src/Pure/Thy/thm_deps.ML	Wed Oct 13 19:41:35 1999 +0200
@@ -75,7 +75,7 @@
       map (#der o rep_thm) thms))));
     val path = File.tmp_path (Path.unpack "theorems.graph");
     val _ = put_graph gra path;
-    val _ = execute ("$ISATOOL browser -d " ^ Path.pack (Path.expand path) ^ " &");
+    val _ = system ("$ISATOOL browser -d " ^ Path.pack (Path.expand path) ^ " &");
   in () end;
 
 end;