title: When a parent process is killed by "kill -9", will subprocess also be killed?
body: <p>One of my colleague told me this morning,  when he killed <a href="http://supervisord.org/" rel="noreferrer">supervisord</a> by "kill -9", the subprocesses of supervisord is not killed.</p>
  
  <p>He is quite sure about that,  but I tried many times and did not find that happen.</p>
  
  <p>So when a parent process is killed by "kill -9", will linux ensure that it's sub-processes also been killed?</p>