错误500 ；End of script output before headers: index.php

public function multi(){		$page = 128;//ajax的分页数		$max_size = 10;//并发数		//url数组		$url_arr = array();		//生成url数组		for($i = 1;$i <= $page; $i++){			$url = 'http://www.wdzj.com/front_select-plat?params=&sort=0&currpage=';			$url .= $i;			$url_arr[] = $url;		}		$mh = curl_multi_init();		//每次只放出$max_size大小的url用来初始化		$count = count($url_arr);		for($i=0;$i<$count;$i++){			$ch = curl_init();			curl_setopt($ch, curlopt_url, $url_arr[$i]);			curl_setopt($ch, curlopt_header, 0);			curl_setopt($ch, curlopt_timeout, 5);			curl_setopt($ch, curlopt_useragent, 'mozilla/5.0 (windows nt 6.1; wow64) applewebkit/537.36 (khtml, like gecko) chrome/44.0.2403.130 safari/537.36');			curl_setopt($ch, curlopt_returntransfer, true);			curl_multi_add_handle($mh, $ch);			$requestmap[] = $ch;			if(count($requestmap)<$max_size && ++$i != $count) continue;//保证数组中每次有$max_size个请求且请求的url还没有用完			$active = null;			//执行批处理句柄			do{				$mrc = curl_multi_exec($mh, $active);			}while($mrc == curlm_call_multi_perform);			while($active && $mrc == curlm_ok){				if(curl_multi_select($mh) != -1){					do{						$mrc = curl_multi_exec($mh, $active);					}while($mrc == curlm_call_multi_perform);				}			}						$json_arr = array();//存放ajax返回的接口数据			//获取资源并且关闭句柄			foreach($requestmap as $ch){				$json_arr[] = curl_multi_getcontent($ch);// 				file_put_contents($i.'.txt', $json);				$error = curl_error($ch);				if($error != '') exit('发生了错误：'.$error);				curl_multi_remove_handle($mh, $ch);			}			unset($requestmap);		}		curl_multi_close($mh);		file_put_contents('1.txt', json_encode($json_arr));	}

[Thu May 05 17:08:52.673028 2016] [core:warn] [pid 20268:tid 320] AH00098: pid file D:/phpStudy/Apache/logs/httpd.pid overwritten -- Unclean shutdown of previous Apache run?[Thu May 05 17:08:52.811036 2016] [mpm_winnt:notice] [pid 20268:tid 320] AH00455: Apache/2.4.10 (Win32) OpenSSL/1.0.1i mod_fcgid/2.3.9 configured -- resuming normal operations[Thu May 05 17:08:52.811036 2016] [mpm_winnt:notice] [pid 20268:tid 320] AH00456: Apache Lounge VC9 Server built: Jul 19 2014 13:20:51[Thu May 05 17:08:52.811036 2016] [core:notice] [pid 20268:tid 320] AH00094: Command line: 'D:\\phpStudy\\Apache\\bin\\httpd.exe -d D:/phpStudy/Apache'[Thu May 05 17:08:52.814036 2016] [mpm_winnt:notice] [pid 20268:tid 320] AH00418: Parent: Created child process 21132[Thu May 05 17:08:54.476131 2016] [mpm_winnt:notice] [pid 21132:tid 336] AH00354: Child: Starting 150 worker threads.[Thu May 05 17:15:20.696222 2016] [core:error] [pid 21132:tid 1724] [client 127.0.0.1:60080] End of script output before headers: index.php

<?phpini_set('display_errors','on');error_reporting(E_ALL);?>