How to redirect all subpages using htaccess and exclude specific URLs?
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I am trying to redirect using htaccess, but I do not know much about htaccess and redirection. What I want to do is:

redirect access to all subpages and directories e.g.

    http://mydomain.com/index.php
    http://mydomain.com/directory/
    http://mydomain.com/new/directory/

to a specific URL on my domain say:

    http://mydomain.com/one

I try to do it with 

    redirect /index.php http://mydomain.com/demo/

But my question is how to EXCLUDE specific URLs and directories from this redirection? How can I make rule to exclude specific pages from being redirected?

Any help is appreciated.