title: Why can't bash recognize the existence of a socket file
body: <p>On a Linux box I want to check if a specific socket file exists. I know the socket files exists, but my checks in bash don't show that to me:</p>
  
  <pre><code>$ ls -l /var/run/supervisor.sock
  srwxrw-rw- 1 root root 0 Jun  3 13:30 /var/run/supervisor.sock  # &lt;== THE FILE EXISTS!!
  $ if [ ! -f /var/run/supervisor.sock ]; then echo 'file does not exist!'; fi
  file does not exist!
  </code></pre>
  
  <p>Why oh why can't bash see that the file exists?</p>