title: bash: sleep process not getting killed
body: <p>I wrote a simple bash script which does nothing but sleeps.</p>
  
  <pre><code>#!/bin/bash
  
  echo "Sleeping..."
  sleep 180s
  </code></pre>
  
  <p>I see two processes running on my system after I run the script:</p>
  
  <pre><code>user 22880  0.0  0.0  12428  1412 pts/28   S+   20:12   0:00 /bin/bash ./sleep.sh
  user 22881  0.0  0.0   7196   356 pts/28   S+   20:12   0:00 sleep 180s
  </code></pre>
  
  <p>I give a <code>SIGTERM</code> to the process with id <code>22880</code> by using <code>kill -15 22880</code> which kills the process. However, after this, I still see the sleep command running which exits after 180 seconds.</p>
  
  <pre><code>user 22881  0.0  0.0   7196   356 pts/28   S    20:12   0:00 sleep 180s
  </code></pre>
  
  <p>Why does this happen? What do I need to do to not leave the <code>sleep 180s</code> process running?</p>