I'm not sure if this is at all possible, but I would like to automatically rewrite a path whenever a page is requested (through apache). I don't want to actually rewrite the URL, but the absolute path the page is retrieved from.

Let me try to explain that more clearly.

I have a directory on my Linux server, say /var/www which serves as the document root for Apache. So when someone requests http://www.mydomain.com/somepage.html, it serves /var/www/somepage.html.

But what I want is that when someone requests http://www.mydomain.com/concepts/clientA/somepage.html, instead of serving /var/www/concepts/clientA/somepage.html, it serves /home/concepts/clientA/somepages.html.

So as soon as the root directory in the url is "concepts", I want it to retrieve the page from the /home/concepts directory.

/homes/concepts/clientA/somepage.html is not directly accessible from the web so I can't use mod-rewrite.

Also, I don't want to create symbolic links for each client because I simply want to create subdirs under the "concepts" directory, and be able to automatically access them over the web.

Hope my question makes any sense.

Sorry, my question above is incomplete (since the easy solution for the above question would be to use the "Alias" directive). Let me try to better explain what I want (it's 2:15am here so bear with me).

My apache directory structure is as follow:

/var/www/htdocs <- apache document root
/var/www/cgi-bin <- cgi-bin script root

In my apache.conf file, I have set

DocumentRoot "/var/www/htdocs"
ServerAlias /cgi-bin/ "/var/www/cgi-bin/"

So when "www.mydomain.com/somepage.html" is requested, "/var/www/htdocs/somepage.html" is served.
And when "www.mydomain.com/cgi-bin/somescript.cgi" is requested, "/var/www/cgi-bin/somescript.cgi" is served.

But now I want some special cases:
When "www.mydomain.com/concepts/clientA/somepage.html" is requested, "/home/concepts/clientA/htdocs/somepage.html" is served.
When "www.mydomain.com/concepts/clientA/cgi-bin/somescript.cgi" is requested, "home/concepts/clientA/cgi-bin/somescript.cgi" is served.

Like I said, I don't want to add a directive for each client. So I don't want this in my apache.conf:

Alias "/concepts/clientA/cgi-bin/" "/home/concepts/clientA/cgi-bin/"
Alias "/concepts/clientA/" "/home/concepts/clientA/htdocs/"
Alias "/concepts/clientB/cgi-bin/" "/home/concepts/clientB/cgi-bin/"
Alias "/concepts/clientB/" "/home/concepts/clientB/htdocs/"
etc.

I want something like this:

Alias "/concepts/*/cgi-bin" "/home/concepts/*/cgi-bin/"
Alias "/concepts/*/" "/home/concepts/*/htdocs/"

Hope that makes sense (like I said, it's 2:15am here and I'm tired ).

Got it. Was easier than I thought it would be:

AliasMatch ^/concepts/(.*?)/(.*) /home/concepts/$1/htdocs/$2
ScriptAliasMatch ^/concepts/(.*?)/cgi-bin/(.*) /home/concepts/$1/cgi-bin/$2

Just never knew those two directives existed.