publish_on_shutdown_test_node.py

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#!/usr/bin/env python
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# Revision $Id: talker.py 4223 2009-04-16 21:47:54Z jfaustwg $

## Simple talker demo that published std_msgs/Strings messages
## to the 'chatter' topic

import rospy
from std_msgs.msg import String

pub = None
# publish a message to subscribers when we die
def talker_shutdown():
    print("I'm dead!")
    pub.publish("I'm dead!")

    # need to sleep a bit to ensure that the message is sent
    # which happens asynchonously
    import time
    time.sleep(2.0)
    
def talker():
    global pub
    pub = rospy.Publisher('chatter', String, queue_size=10)
    rospy.init_node('talker', anonymous=True)

    # register talker_shutdown() to be called when rospy exits
    rospy.on_shutdown(talker_shutdown)
    
    import time
    time.sleep(2.0)

    rospy.signal_shutdown('test done')
        
if __name__ == '__main__':
    talker()