Drupal Display PHP Errors on One Domain of Multi Site

When using a multi-site setup, You may want errors only to appear for one site. In that case, use $_SERVER[‘HTTP_HOST’] in an if statement to only display PHP error messages for the domain of your choice:

<?php
if ($_SERVER['HTTP_HOST']==='specific.domain-you-want.here') {
  error_reporting(E_ALL);
  ini_set('display_errors', TRUE);
  ini_set('display_startup_errors', TRUE);
}
?>