src/Pure/Admin/build_e.scala

         progress_stderr = progress.echo_if(verbose, _)).check
 
 
       /* install */
 
-      File.copy(build_dir + Path.basic("COPYING"), component_dir + Path.basic("LICENSE"))
+      Isabelle_System.copy_file(build_dir + Path.basic("COPYING"),
+        component_dir + Path.basic("LICENSE"))
 
       val install_files = List("epclextract", "eprover", "eprover-ho")
       for (name <- install_files ::: install_files.map(_ + ".exe")) {
         val path = build_dir + Path.basic("PROVER") + Path.basic(name)
-        if (path.is_file) File.copy(path, platform_dir)
+        if (path.is_file) Isabelle_System.copy_file(path, platform_dir)
       }
       Isabelle_System.bash("if [ -f eprover-ho ]; then mv eprover-ho eprover; fi",
         cwd = platform_dir.file).check