HADOOP-7971. Adding back job/pipes/queue commands to bin/hadoop for backward compatibility. Contributed by Prashath Sharma.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1232322 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -276,6 +276,9 @@ Release 0.23.1 - Unreleased
    HADOOP-7974. TestViewFsTrash incorrectly determines the user's home
    directory. (harsh via eli)
 
+   HADOOP-7971. Adding back job/pipes/queue commands to bin/hadoop for
+   backward compatibility. (Prashath Sharma via acmurthy) 
+
 Release 0.23.0 - 2011-11-01 
 
   INCOMPATIBLE CHANGES

hadoop-common-project/hadoop-common/src/main/bin/hadoop

@@ -60,8 +60,24 @@ case $COMMAND in
     elif [ -f "${HADOOP_PREFIX}"/bin/hdfs ]; then
       exec "${HADOOP_PREFIX}"/bin/hdfs $*
     else
-      echo "HDFS not found."
-      exit
+      echo "HADOOP_HDFS_HOME not found!"
+      exit 1
+    fi
+    ;;
+
+  #mapred commands for backwards compatibility
+  pipes|job|queue)
+    echo "DEPRECATED: Use of this script to execute mapred command is deprecated." 1>&2
+    echo "Instead use the mapred command for it." 1>&2
+    echo "" 1>&2
+    #try to locate mapred and if present, delegate to it.
+    if [ -f "${HADOOP_MAPRED_HOME}"/bin/mapred ]; then
+      exec "${HADOOP_MAPRED_HOME}"/bin/mapred $*
+    elif [ -f "${HADOOP_PREFIX}"/bin/mapred ]; then
+      exec "${HADOOP_PREFIX}"/bin/mapred $*
+    else
+      echo "HADOOP_MAPRED_HOME not found!"
+      exit 1
     fi
     ;;