diff -r d58da36d1a30 -r c352f679dcca src/Pure/System/isabelle_system.scala
--- a/src/Pure/System/isabelle_system.scala	Mon Dec 28 16:24:19 2009 +0100
+++ b/src/Pure/System/isabelle_system.scala	Mon Dec 28 16:45:01 2009 +0100
@@ -90,8 +90,7 @@
         case Some(path) => path
       }
 
-    val dump = File.createTempFile("isabelle", null)
-    try {
+    Library.with_tmp_file("isabelle_settings") { dump =>
       val cmdline = shell_prefix :::
         List(isabelle_home + "/bin/isabelle", "getenv", "-d", dump.toString)
       val (output, rc) =
@@ -108,7 +107,6 @@
         ("HOME" -> java.lang.System.getenv("HOME")) +
         ("PATH" -> java.lang.System.getenv("PATH"))
     }
-    finally { dump.delete }
   }