Adding PHP command in HTML generated pages...
 

I have a PHP script that redirects web pages based on country installed on my server. It requires a PHP command be place as the very first line of code, above the first html tag (<?PHP $rv_path="...). I would like to add this to the x-cart html generated catalog pages as well. Can anyone tell me which template I can add this to, and in what format it would be added, so that all x-cart html pages have the command at the very top?

You can't add PHP to the HTML catalog as it generates .html files which won't get processed as php scripts by your server. If you have a dedicated server, then it's something that can be changed, but would require more than light modification to the HTML catalog generator.

You might consider looking into an apache solution to do this for you (if it's based on languages).

Hope this helps.