WordPress Any URL - A quick and dirty way of allowing WordPress to run on any URL, without having to replace URLs in the database. It will figure out the home URL, based on the current hostname and relative path from the server's root directory. It will also re-write existing links with the current site, using output buffering. eg. http://oldser…

wp-config.php

// Add whatever URLs you want to replace with the current home URL
$replace_urls = array('http://exampleoldsite.com/mysite');

$uri = str_replace("{$_SERVER['DOCUMENT_ROOT']}/", '', dirname(__FILE__));
$home_url = sprintf('%s://%s/%s', $_SERVER['SERVER_PORT'] == 443 ? 'https' : 'http', $_SERVER['SERVER_NAME'], $uri);
define('WP_SITEURL', $home_url); define('WP_HOME', $home_url);
function replace_old_urls($html) { global $replace_urls; return str_replace($replace_urls, WP_SITEURL, $html); }
ob_start('replace_old_urls');