--- a/jdk/test/java/nio/file/Files/PrintFileTree.java	Tue Feb 23 18:19:53 2010 +0000
+++ b/jdk/test/java/nio/file/Files/PrintFileTree.java	Tue Feb 23 18:21:31 2010 +0000
@@ -28,27 +28,33 @@
 
 /**
  * Invokes Files.walkFileTree to traverse a file tree and prints
- * each of the directories and files. The -L option causes symbolic
- * links to be followed.
+ * each of the directories and files. The -follow option causes symbolic
+ * links to be followed and the -printCycles option will print links
+ * where the target of the link is an ancestor directory.
  */
 
 public class PrintFileTree {
 
     public static void main(String[] args) throws Exception {
         boolean followLinks = false;
-        Path dir;
-
-        if (args[0].equals("-L")) {
-            followLinks = true;
-            dir = Paths.get(args[1]);
-        } else {
-            dir = Paths.get(args[0]);
+        boolean printCycles = false;
+        int i = 0;
+        while (i < (args.length-1)) {
+            switch (args[i]) {
+                case "-follow"      : followLinks = true; break;
+                case "-printCycles" : printCycles = true;  break;
+                default:
+                    throw new RuntimeException(args[i] + " not recognized");
+            }
+            i++;
         }
+        Path dir = Paths.get(args[i]);
 
         Set<FileVisitOption> options = new HashSet<FileVisitOption>();
         if (followLinks)
             options.add(FileVisitOption.FOLLOW_LINKS);
 
+        final boolean reportCycles = printCycles;
         Files.walkFileTree(dir, options, Integer.MAX_VALUE, new FileVisitor<FileRef>() {
             public FileVisitResult preVisitDirectory(FileRef dir) {
                 System.out.println(dir);
@@ -59,7 +65,8 @@
                 return FileVisitResult.CONTINUE;
             }
             public FileVisitResult visitFile(FileRef file, BasicFileAttributes attrs) {
-                System.out.println(file);
+                if (!attrs.isDirectory() || reportCycles)
+                    System.out.println(file);
                 return FileVisitResult.CONTINUE;
             }
             public FileVisitResult postVisitDirectory(FileRef dir, IOException exc) {

--- a/jdk/test/java/nio/file/Files/walk_file_tree.sh	Tue Feb 23 18:19:53 2010 +0000
+++ b/jdk/test/java/nio/file/Files/walk_file_tree.sh	Tue Feb 23 18:21:31 2010 +0000
@@ -61,12 +61,20 @@
 diff out1 out2
 if [ $? != 0 ]; then failures=`expr $failures + 1`; fi
 
-# repeat test following links (use -follow instead of -L
-# to allow running on older systems)
-$JAVA PrintFileTree -L "$ROOT" > out1
-find "$ROOT" -follow > out2
+# repeat test following links. Some versions of find(1) output
+# cycles (sym links to ancestor directories), other versions do
+# not. For that reason we run PrintFileTree with the -printCycles
+# option when the output without this option differs to find(1).
+find "$ROOT" -follow > out1
+$JAVA PrintFileTree -follow "$ROOT" > out2
 diff out1 out2
-if [ $? != 0 ]; then failures=`expr $failures + 1`; fi
+if [ $? != 0 ];
+  then 
+    # re-run printing cycles to stdout
+    $JAVA PrintFileTree -follow -printCycles "$ROOT" > out2
+    diff out1 out2
+    if [ $? != 0 ]; then failures=`expr $failures + 1`; fi
+  fi
 
 # test SKIP_SIBLINGS
 $JAVA SkipSiblings "$ROOT"