How do I run a site from a sub-directory? Maybe I'm making this way more complicated than I need to, but I want to serve my Drupal site that I've installed at example.com/drupal from example.com.  This particular site is an add-on site on my shared host, so the actual file structure is public_html/example.com/drupal.  What do I need to modify: .htaccess or add a redirect in cPanel?  I can't imagine I'm doing anything radical here, but there's no clear-cut answer in all my searching.
I just had the same problem. I have solved it with htaccess file(ie. not nginx) in the root directory with the following code(although I have tested it only with simple index file, not with fully installed Drupal):

&lt;IfModule mod_rewrite.c&gt;
  RewriteEngine on
  RewriteCond %{REQUEST_URI} !drupal/
  RewriteRule (.*) /drupal/$1 [L]
&lt;/IfModule&gt;