Running CodeIgnitor and WordPress in same root directory

Once we had a situation of running WordPress based site and CodeIgnitor based application in same root directory. The main site was built in WordPress and the SAAS application was built in CodeIgnitor. There was one issue which was prohibiting us to have files of both apps in same directory level. Both application had their own “index.php”. So to avoid file conflict we renamed renamed CI’s index.php to “ci-index.php”. Then used Apache’s mod_rewrite module to redirect CI based SAAS application’s request to ci-index.php. Fortunately all the SAAS application’s path were starting with “/admin” so we added following rewrite condition in “.htaccess” file.

RewriteCond %{REQUEST_URI} ^/admin/(.*) RewriteRule ^(.*)$ /ci-index.php?/$1 [L]

If you know any better way to implement this do post your thoughts here.