Hi, I'm just wondering, what is the right output of below code should be ob_start(function($o) { fwrite(STDERR, $o); }); echo 'hello'; ob_end_clean(); Does it should print "hello" or does it should print nothing? In PHP 5.3, it prints hello, but in 5.4.0 it prints nothing. Looking at the C code of PHP 5.4, it explicitly discards the output buffer before calling the callback, except when flushing or when using the internal callback handler. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php