svn commit: r1449162 - /hadoop/common/branches/branch-2/hadoop-yarn-project/hadoop-yarn/bin/yarn

[at...@apache.org]

Author: atm
Date: Fri Feb 22 18:37:30 2013
New Revision: 1449162

URL: http://svn.apache.org/r1449162
Log:
HADOOP-9267. hadoop -help, -h, --help should show usage instructions. Contributed by Andrew Wang.

Modified:
    hadoop/common/branches/branch-2/hadoop-yarn-project/hadoop-yarn/bin/yarn

Modified: hadoop/common/branches/branch-2/hadoop-yarn-project/hadoop-yarn/bin/yarn
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-2/hadoop-yarn-project/hadoop-yarn/bin/yarn?rev=1449162&r1=1449161&r2=1449162&view=diff
==============================================================================
--- hadoop/common/branches/branch-2/hadoop-yarn-project/hadoop-yarn/bin/yarn (original)
+++ hadoop/common/branches/branch-2/hadoop-yarn-project/hadoop-yarn/bin/yarn Fri Feb 22 18:37:30 2013
@@ -53,13 +53,7 @@ DEFAULT_LIBEXEC_DIR="$bin"/../libexec
 HADOOP_LIBEXEC_DIR=${HADOOP_LIBEXEC_DIR:-$DEFAULT_LIBEXEC_DIR}
 . $HADOOP_LIBEXEC_DIR/yarn-config.sh
 
-cygwin=false
-case "`uname`" in
-CYGWIN*) cygwin=true;;
-esac
-
-# if no args specified, show usage
-if [ $# = 0 ]; then
+function print_usage(){
   echo "Usage: yarn [--config confdir] COMMAND"
   echo "where COMMAND is one of:"
   echo "  resourcemanager      run the ResourceManager" 
@@ -76,6 +70,16 @@ if [ $# = 0 ]; then
   echo " or"
   echo "  CLASSNAME            run the class named CLASSNAME"
   echo "Most commands print help when invoked w/o parameters."
+}
+
+cygwin=false
+case "`uname`" in
+CYGWIN*) cygwin=true;;
+esac
+
+# if no args specified, show usage
+if [ $# = 0 ]; then
+  print_usage
   exit 1
 fi
 
@@ -83,6 +87,14 @@ fi
 COMMAND=$1
 shift
 
+case $COMMAND in
+  # usage flags
+  --help|-help|-h)
+    print_usage
+    exit
+    ;;
+esac
+
 if [ -f "${YARN_CONF_DIR}/yarn-env.sh" ]; then
   . "${YARN_CONF_DIR}/yarn-env.sh"
 fi