1--TEST-- 2ob_start(): ensure buffers can't be added from within callback. 3--FILE-- 4<?php 5 6/* 7 * proto bool ob_start([ string|array user_function [, int chunk_size [, bool erase]]]) 8 * Function is implemented in main/output.c 9*/ 10 11function f($str) { 12 ob_start(); 13 echo "hello"; 14 ob_end_flush(); 15 return $str; 16} 17 18 19var_dump(ob_start('f')); 20echo "done"; 21?> 22--EXPECTF-- 23Fatal error: ob_start(): Cannot use output buffering in output buffering display handlers in %s on line 9