title: curl works fine in command line, but not in php
body: <p>I use curl to retrieve the contents of a url from within PHP. It works fine for most url's, but for some, it only returns an empty string ("curl"ing such url's from command line works just fine).
  Here's how I run curl:</p>
  
  <pre><code>$curl_session = curl_init($site-&gt;url);
  curl_setopt($curl_session, CURLOPT_HEADER, 0);
  curl_setopt($curl_session, CURLOPT_RETURNTRANSFER, 1);
  curl_setopt($curl_session, CURLOPT_CONNECTTIMEOUT, TIMEOUT);
  $output = curl_exec($curl_session);
  curl_close($curl_session);
  </code></pre>
  
  <p>I also checked and curl doesn't seem to give any errors.</p>