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<?php function siteURL() { return "http://www.luntech.com?dev=desktop&name=value"; } define('SITE_URL', siteURL()); //returns http://example.com/dir/ define('CKEDITOR', 'http://m.luntech.com/default.asp?dev=mobile&name=value'); // ignore the previous code is just to emulate your constants and functions // the answer is the following line: echo str_replace(SITE_URL,'',CKEDITOR); ?>
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
http://m.luntech.com/default.asp?dev=mobile&name=value

preferences:
289.91 ms | 406 KiB | 456 Q