How should a native extension check which CMS is in use?

[SarahG (FountainTribe)]

I have a native CiviCRM extension that is working well. (You can try it out at: https://civicrm.org/extensions/fancy-tokens)   I would like to enhance it to produce tokens with hyperlinks to Drupal WebForms with the checksum, but only if CiviCRM is running under Drupal.   

What is the recommended way to determine the CMS in use, from inside my extension?

[Coleman Watts]

Code: [Select]

$config = CRM_Core_Config::singleton();
if ($config->userSystem->is_drupal) ...


[SarahG (FountainTribe)]

That works perfectly. Thanks.