cannot launch node of type [closed]

edit

ros indigo. ubuntu 14.04 trusty.

this is the launch xml file commandclient.launch :

<launch>

<!-- Start the command action client to take commands -->
  <node name="command_action_client"  pkg="hal_main" type="commandclient"  output="screen" > 
  </node>

</launch>

roslaunch hal_main commandclient.launch :

... logging to /home/jaysin/.ros/log/be04aa0e-5080-11e4-ab58-28e347742258/roslaunch-jaysin-24849.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://jaysin:60903/

SUMMARY
========

PARAMETERS
 * /rosdistro: indigo
 * /rosversion: 1.11.9

NODES
  /
    command_action_client (hal_main/commandclient)

ROS_MASTER_URI=http://localhost:11311

core service [/rosout] found
ERROR: cannot launch node of type [hal_main/commandclient]: can't locate node [commandclient] in package [hal_main]
No processes to monitor
shutting down processing monitor...
... shutting down processing monitor complete

rosrun hal_main commandclient:

[rosrun] Couldn't find executable named commandclient below /home/jaysin/ros/clam3/src/hal_main

rospack find hal_main :

/home/jaysin/ros/clam3/src/hal_main

echo $ROS_PACKAGE_PATH :

/home/jaysin/ros/clam3/src:/opt/ros/indigo/share:/opt/ros/indigo/stacks

launches from other packages work fine. i have rebuilt everything after deleting devel and build.