1--TEST-- 2ob_start(): Ensure unerasable buffer cannot be accessed or erased by ob_get_clean(). 3--FILE-- 4<?php 5function callback($string) { 6 static $callback_invocations; 7 $callback_invocations++; 8 return "[callback:$callback_invocations]$string\n"; 9} 10 11ob_start('callback', 0, false); 12 13echo "This call will fail to obtain the content, since it is also requesting a clean:\n"; 14$str = ob_get_clean(); 15var_dump($str); 16?> 17--EXPECTF-- 18[callback:1]This call will fail to obtain the content, since it is also requesting a clean: 19 20Notice: ob_get_clean(): failed to delete buffer callback in %s on line 11 21bool(false) 22