URL of referring site from 302 redirect? (PHP)

[kbweb]

I'm working on a little project and I know how to get the URL of the referring site:

$url = $_SERVER['HTTP_REFERER'];

The only problem is it doesn't seem to work with a 302 redirect. For example:

I set up a 302 URL forwarding redirect for site1.com, site2.com, site3.com all pointing to site.com. How can I find which site was forwarded?

Thanks

 

[Kate]

You may have to use a parameter in the redirect URL.
Also keep in mind the refer is set by the browser. It may not be present at all sometimes so don't always expect it.