title: Unix permissions
body: <p>I have a file of which I need to change contents, that has these permissions:</p>
  
  <pre><code>-rw-r--r-- 
  </code></pre>
  
  <p>How do I find out which permissions group I belong to, so I can do a chmod command?</p>
  
  <p>I just tried to do chmod and I got an error:</p>
  
  <pre><code>$ chmod 777 hosts
  chmod: Unable to change file mode on hosts: Operation not permitted
  </code></pre>
  
  <p>Here is my ls -l</p>
  
  <pre><code>-rw-r--r--  1 root  wheel  313 Apr 16 13:04 hosts
  </code></pre>