how can i rewrite my url for only certain pages - php

Question

How can I use .htaccess to rewrite URL for certain pages only?
For example, I want it to work on index.php but not the rest of the pages on the site or on all pages but index.php.
I run in to issues with sub domains and php scripts where the URL redirecting that I am using will mess up stuff. Below is an example of the kind of script I want to use.
Options +FollowSymLinks -MultiViews
# Turn mod_rewrite on
RewriteEngine On
RewriteBase /
## If the request is for a valid directory
RewriteCond %{REQUEST_FILENAME} -d [OR]
## If the request is for a valid file
RewriteCond %{REQUEST_FILENAME} -f [OR]
## If the request is for a valid link
RewriteCond %{REQUEST_FILENAME} -l
## don't do anything
RewriteRule ^ - [L]
RewriteRule ^([^/]+)/([^/]+)/?$ index.php/?node=$1&id=$2 [L,QSA]
RewriteRule ^([^/]+)/?$ index.php/?node=$1 [L,QSA]
Can anyone point me in the right direction?

Answer 1

You can pass URL as REQUEST_URI server variable:
RewriteCond %{REQUEST_URI} ^(your_url)$
RewriteRule %1 do_some_stuff
As an example:
RewriteCond %{REQUEST_URI} ^index.php$
RewriteRule %1 - [F]
Or just pass it in RewriteRule:
RewriteRule ^index.php$ do_some_stuff

Answer 2

You should check out RewriteCond (conditions) for .htaccess
Check http://www.addedbytes.com/articles/for-beginners/url-rewriting-for-beginners/ for a lot of information and examples.
You could also write a rule just for index.php and then flag it as the last rule [l]
RewriteRule ^/index.php(.*) /index.php$1 [L]
RedirectRule ^/(.*)$ /index.php?path=$1 [L]