I’m trying to make an address redirect to another one without actually changing the URL in the browser address bar.
User go to /path/page.php and see what is displayed on /path/index.php.
In the address bar the URL remains /path/page.php.
This is the code for the redirection:
Options +FollowSymLinks
RewriteEngine On
RewriteRule page.php index.php [NC]
I’m wondering if I need to use [P] for this task :/
[P] is a proxy flag, you need it only for silent redirection to another domain or web-server (in this case Apache works like HTTP proxy). In your case page.php and index.php reside on the same server, so [P] flag is useless.