HTTP_REFERER in error pages

How can I found out who referred to a non-existing page

[adb64]

I've made my own error page for 404 errors (error404.php) and added it to my .htaccess file. So far so good.
This PHP script creates a log file containing all 404 errors, but I want to add the referrer from $HTTP_REFERER so I know who is referring to a page that doesn't exist anymore on my site. Just accessing $HTTP_REFERER won't work (this works only when from a local page on my site I access e.g. an image which no longer exists).

Anyone any idea how to solve this?

Thanx

[seomike2003]

$_SERVER['HTTP_REFFER']

[Timotheos]

Mabye $_SERVER['REQUEST_URI']

http://www.webmasterworld.com/forum88/1578.htm [webmasterworld.com]

[adb64]

Seomike2003 and Timotheus thanks,

but the $_SERVER['HTTP_REFERER'] is empty in a custom error page. But I did some research and discovered that this info is available via getenv('HTTP_REFERER').

Maybe this may help other people with the same problem.

[Timotheos]

Hmmmm... I don't understand why getenv() would work while the other one didn't. Maybe something to do with php running in cgi vs apache module?

[ergophobe]

I have a custom error page that has a double redirect since I use mod_rewrite in .htaccess to make "friendly urls" and then if it can't find the page, the php script displays an error page.

It does not actually return a 404, but that's just because I don't make it send the 404 header.

In any case, in both Linux and Windows, this works fine:

echo $_SERVER['HTTP_REFERER']