CHUKWA-677. Added pid file check before starting processes. (Sreepath…

…i Prasanna via Eric Yang)

git-svn-id: https://svn.apache.org/repos/asf/incubator/chukwa/trunk@1424080 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -30,6 +30,8 @@ Trunk (unreleased changes)
 
   BUGS
 
+    CHUKWA-677. Added pid file check before starting processes. (Sreepathi Prasanna via Eric Yang)
+
     CHUKWA-676. Exclude temporarily data from release audit tools. (Eric Yang)
 
     CHUKWA-672. Fix adaptor not found in checkpoint after shutdown. (shreyas subramanya via asrabkin)

bin/chukwa

@@ -160,12 +160,18 @@ elif [ "$COMMAND" = "tail" ]; then
   exit 0
 fi
 
+pid="${CHUKWA_PID_DIR}/$PID.pid"
 if [ "$1" = "stop" ]; then
-  if [ -e ${CHUKWA_PID_DIR}/$PID.pid ]; then 
-    kill -TERM `cat ${CHUKWA_PID_DIR}/$PID.pid`
+  if [ -e $pid ]; then 
+    kill -TERM `cat $pid`
   else 
     echo "Cannot find PID file - $PID.pid; NO $PID to stop";
   fi
+elif [ -f $pid ]; then
+ if kill -0 `cat $pid` > /dev/null 2>&1; then
+    echo $command running as process `cat $pid`.  Stop it first.
+    exit 1
+ fi
 else 
   # run command
   if [ "$BACKGROUND" = "false" ]; then