setup Multi Multi-site with one installation?

I’ve ended up with using such solution:

1) Created folders like:

wp-base
- wp-admin
- wp-includes
- .... all wp-php files

and I’ve created “symlink” that 2-folder and wp standard php files inside other folders:

my-wp-1
- wp-content & wp.config.php & htaccess
my-wp-2
- wp-content & wp.config.php & htaccess

The only thing I had to do is to use this in the top of wp-load.php:

$fold=filter_var($_SERVER['HTTP_HOST'], SANITIZE_STRING);
/** Define ABSPATH as this file's directory */
if ( ! defined( 'ABSPATH' ) ) {
    define( 'ABSPATH', dirname(dirname( __FILE__ )). "/$fold/" );
}

There seems no need of adding define( 'WP_CONTENT_DIR', __DIR__.'/wp-content' ); in wp-config.