title: Is there an HTTP header to say what base URL to use for relative links?
body: <p>I am retrieving a page from another host, and then initializing the form with data from a database before sending it on to the user.</p>
  
  <p>I need to make the URLs in <code>href</code> and <code>src</code> attributes absolute, so that the browsers load them from the right place.</p>
  
  <p>Can I set an HTTP header to cause this to happen without modifying the HTML?</p>