title: Php - Subtracting days from gmdate() date
body: <p>I would like to subtract 180 days from a GMDATE() (for UTC purposes) I have in a PHP script. I have just looked on SO but hardly anybody is using gmdate().</p>
  
  <p>This is what I have:</p>
  
  <pre><code>$from_date = gmdate("Y-m-d H:i:s");
  </code></pre>
  
  <p>Is there a simple way to subtract X amount of days from this, without using a different function completely? Or should I be doing it another way?</p>