3v4l.org

run code in 300+ PHP versions simultaneously
<?php function callback($buffer, $status) { return "callback $buffer"; } ob_start( 'callback', 0, PHP_OUTPUT_HANDLER_FLUSHABLE | PHP_OUTPUT_HANDLER_REMOVABLE); echo 'test'; echo ob_get_clean(); //this should not work as no CLEANABLE flag was set on ob_start //ob_end_clean is ran as well //ob_clean -> failed to delete buffer notice echo "\n".ob_get_level();

preferences:
60.67 ms | 410 KiB | 5 Q