Write ActionScript Value to File Via php

I have some XML I've edited in ActionScript that I would like to save locally via php. My php script (called writeFile.php) is the following:

<?php
  $variable = $_POST['data'];
  $file = "tmp.xml";
  $fh = fopen($file, 'w');
  fwrite($fh, $variable);
  fclose($fh);
  echo "Done!";
?>

My ActionScript is the following:

var loader:URLLoader = new URLLoader();
var request:URLRequest = new URLRequest("writeFile.php");
var vars:URLVariables = new URLVariables();
vars.data = xml.toXMLString();
request.data = vars;
request.method =开发者_如何转开发 URLRequestMethod.POST;
loader.addEventListener(Event.COMPLETE,onComplete);
loader.load(request);

However, no file is being created, and thus obviously nothing is being written to it.

---

Make sure that you have write permission for that directory on the server. And in the onComplete function look for the server response to make sure you're seeing "Done!"