How to mod_rewrite for HTTP_HOST?

I am working in a shared account on 开发者_运维技巧a hosting provider with several domain names. Goal is to have each domain name have their own virtual directories. In my personal configured htdocs/ directory, I have a subdirectory set up for each domain name, something quite similar to this:

htdocs/
    foo.com/
        index.html
    bar.com/
        test.txt

I'd like to serve http://foo.com/index.html instead of http://foo.com/foo.com/index.html.

Is this the proper way to set up .htaccess in htdocs/?

RewriteEngine on
RewriteCond %{HTTP_HOST} .*foo\.com [NC]
RewriteRule ^/(.*)$ /foo.com/$1 [L]

I assume no as this does not appear to be working and I'm not granted access to error logs. What is the proper syntax?

You shouldn't have to set up .htaccess rules for different domains like that if your on a shared account. Most hosting providers allow you the capability to set up add-on domains, which sets up the proper mappings for you.