Description:
------------
---
From manual page: http://www.php.net/function.readfile#refsect1-function.readfile-examples
---

This is a documentation problem. The header
'Cache-Control: must-revalidate, post-check=0, pre-check=0'
in the example can cause MSIE to rapidly re-download, wasting massive bandwith in the worst case (in my case one original request for a 14 MB file caused 469 automatic subsequent downloads by MSIE). It would be best to remove that header from the example.
Background info can be found here:
http://blogs.msdn.com/b/ie/archive/2006/06/01/613132.aspx
(It does NOT only affect IE 7 Beta 2 as the article may make it seem. I was able to verify the problem in IE 9).

Test script:
---------------
Just the example script from the docs with any file.

Expected result:
----------------
The file should be downloaded only once per request.

Actual result:
--------------
One original request for a 14 MB file caused 469 automatic subsequent downloads by MSIE when the 'Cache-Control: must-revalidate, post-check=0, pre-check=0' header was set.