Why redirect keeps changing address bar

Here is code:

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_URI} !^/rt/
RewriteRule ^(.*)$ /rt/$1 [L]
</IfModule>

There is no [R], but it keeps changing address bar location. It set redirect 302...

I need to change root folder to /rt/ folder, but without changing location in address bar. I can't use anything beside .htaccess file...

I want users when visit: http://domain.com/index.php

see

http://domain.com/index.php

but open http://domain.com/开发者_Python百科rt/index.php

This index.php is example file, I need this working for every file... Without changing location in browser address bar...

How about just using Alias?

Alias / /rt

If not, make sure you have mod_proxy enabled, and try this:

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{REQUEST_URI} !^/rt/
    RewriteRule ^(.*)$ /rt/$1 [PL]
</IfModule>