Domain alias redirection with PHP?

[Tim356]

I've got 1 domain and 3 alias' pointing to that 1 domain. On the server is a forum and in the forum are several different categories of discussion (funny that).

Anyway, I want the main domain to point to the home page of the forum and the others to point to different categories. So, for example this domain: www.category1.com would be redirected to the category 1 forum url.

Is there a way with PHP that I can find out how the user is getting to the site? Would a referer function work for this? If I can tell that the user typed in www.category1.com and was brought to www.mainforum.com then I could write a script to redirect to category 1 forum. Does that make sense? Any ideas?

I've tried using

PHP: Select all

$ref=($_SERVER['HTTP_REFERER']);
if($ref=="http://www.category1.com"){
header("Location: http://www.mainforum.com/forum/category1url");
}
else
{
header("Location: http://www.mainforum.com/forum/");
} 

but that didn't work.

[grahame]

The HTTP_REFERER is for the previous page - the one from which your user followed a link to get to your site. The HTTP_HOST is the host name through which the current host was contacted.

We have several domains with the same main section and we bring in the following from an include file:

Code: Select all

$host = explode(".",$_SERVER[HTTP_HOST]);
$sitefirst = $host[0];
$sitelast = $host[count($host)-1];

and we're then set up (for example) with "net", "uk" or "com" in $sitelast and with "www", "java" or "ireland" in $sitefirst ... so that we have one set of site files but serve subtley varied content. We even switch content completely on occasions to an alternative page without the need for a messy redirect. From later in our header file:

Code: Select all

$page = explode("/",substr($_SERVER[SCRIPT_NAME],1));
$filename = $page[count($page)-1];
$fullfilename = implode("_",$page);
$alternate = "$_SERVER[DOCUMENT_ROOT]/alternate/$host[0]_$fullfilename";
if (file_exists($alternate)) {
include ($alternate);
exit ();
}

[Tim356]

Thanks Grahame, will try that.