htaccess redirect only if domain matches

Question

I have a problem where I need to redirect my domain before it hits php. By the time it hits the ability to execute a header, it is too late.

How can I do

Answer 1

Using mod_rewrite

RewriteEngine On
RewriteCond %{HTTP_HOST} ^www\.example\.com [NC]
RewriteRule ^(.*)$ http://www.domain.com/$1 [R,L]