title: Can PHP be set to never cache a response, and always send something fresh to the page?
body: <p>I have a webpage which pulls in an XML news feed and I don't want the page to cache it so that the XML feed displayed is most recent.</p>
  
  <p>I tried this already so the cache is reset every 1800 seconds:</p>
  
  <pre><code>$header[] = "Cache-Control: max-age=1800";
  </code></pre>
  
  <p>Didn't seem to work.</p>
  
  <p>So what could I try to make the webpage auto refresh the XML in the PHP?</p>