$t('Image CAPTCHA requires GD library'), 'description' => $t( 'The Image CAPTCHA module can not be installed because your PHP setup does not provide the GD library, which is required to generate images.', array('!gddoc' => 'http://www.php.net/manual/en/book.image.php') ), 'severity' => REQUIREMENT_ERROR, ); } } return $requirements; } /** * On uninstall: remove module variables and clear variable cache. */ function image_captcha_uninstall() { db_delete('variable') ->condition('name', db_like('image_captcha_') . '%', 'LIKE') ->execute(); cache_clear_all('variables', 'cache'); }