HADOOP-8074. Small bug in hadoop error message for unknown commands. Contributed by Colin Patrick McCabe

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1244766 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -190,6 +190,9 @@ Release 0.23.2 - UNRELEASED
     Double.MAX_VALUE) to avoid making Ganglia's gmetad core. (Varun Kapoor
     via mattf)
 
+    HADOOP-8074. Small bug in hadoop error message for unknown commands.
+    (Colin Patrick McCabe via eli)
+
 Release 0.23.1 - 2012-02-08 
 
   INCOMPATIBLE CHANGES

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FsShell.java

@@ -269,7 +269,15 @@ public class FsShell extends Configured implements Tool {
   
   private void displayError(String cmd, String message) {
     for (String line : message.split("\n")) {
-      System.err.println(cmd.substring(1) + ": " + line);
+      System.err.println(cmd + ": " + line);
+      if (cmd.charAt(0) != '-') {
+        Command instance = null;
+        instance = commandFactory.getInstance("-" + cmd);
+        if (instance != null) {
+          System.err.println("Did you mean -" + cmd + "?  This command " +
+              "begins with a dash.");
+        }
+      }
     }
   }