MAPREDUCE-5033. mapred shell script should respect usage flags (--help -help -h). Contributed by Andrew Wang.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1450585 13f79535-47bb-0310-9956-ffa450edef68

hadoop-mapreduce-project/CHANGES.txt

@@ -8,6 +8,9 @@ Release 2.0.4-beta - UNRELEASED
 
   IMPROVEMENTS
 
+    MAPREDUCE-5033. mapred shell script should respect usage flags
+    (--help -help -h). (Andrew Wang via atm)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-mapreduce-project/bin/mapred

@@ -50,6 +50,14 @@ fi
 COMMAND=$1
 shift
 
+case $COMMAND in
+  # usage flags
+  --help|-help|-h)
+    print_usage
+    exit
+    ;;
+esac
+
 if [ "$COMMAND" = "job" ] ; then
   CLASS=org.apache.hadoop.mapred.JobClient
 elif [ "$COMMAND" = "queue" ] ; then