用stream_系列函数实现远程文件本地化，怎么防止卡死

用stream_系列函数实现远程文件本地化，如何防止卡死
还是我前两天写的代码，已经用于采集内容了，今天用来改进采集到的内容中的图片等远程文件的本地化，有时候还是会卡死，高手看看如何能防止卡死。
代码如下，这个代码还是提供两种方式实现本地化进行比较，时事证明这种流方式实现效率是提高了。

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?php $dir = str_replace('\\', '/', dirname(__FILE__)) . '/';$timeStart = microtime(true);$data = '';$urls = array('http://www.jxcms.com/upload/2011/0518/0337319304.jpg', 'http://www.jxcms.com/upload/2011/0310/0951568835.jpg', 'http://www.tzksgs.com/upload/banner1.jpg', 'http://www.tzksgs.com/upload/banner2.jpg');foreach($urls as $url) {    copy($url, $dir . 'a_' . basename($url));}$timeEnd = microtime(true);echo sprintf("Spend time: %s second(s)\n", $timeEnd - $timeStart), '<br>';$timeStart = microtime(true);function getMoreContent($urls) {    $timeout = 30;    $rs = array();    $sockets = array();    $userAgent = $_SERVER['HTTP_USER_AGENT'];    foreach($urls as $id =&gt; $url) {        $tmp = parse_url($url);        $host = $tmp['host'];        $path = isset($tmp['path'])?$tmp['path']:'/';        empty($tmp['query']) or $path .= '?' . $tmp['query'];        if (empty($tmp['port'])) {            $port = $tmp['scheme'] == 'https'?443:80;        } else $port = $tmp['port'];        $fp = stream_socket_client("$host:$port", $errno, $errstr, $timeout);        if ($fp) {            $rs[$id] = '';            $sockets[$id] = $fp;            fwrite($fp, "GET $path HTTP/1.1\r\nHost: $host\r\nUser-Agent: $userAgent\r\nConnection: Close\r\n\r\n");        }    }    // Now, wait for the results to come back in    while (count($sockets)) {        $read = $sockets;        // This is the magic function - explained below        if (stream_select($read, $write = null, $e = null, $timeout)) {            // readable sockets either have data for us, or are failed connection attempts            foreach ($read as $r) {                $id = array_search($r, $sockets);                $data = fread($r, 8192);                if (strlen($data) == 0) {                    fclose($r);                    $tmp = explode("\r\n\r\n", $rs[$id], 2);                    $rs[$id] = strpos($tmp[0], '200')?$tmp[1]:'';                    unset($sockets[$id]);                } else $rs[$id] .= $data;            }        }    }    return $rs;}$rs = getMoreContent($urls);foreach($rs as $k =&gt; $v) {    @file_put_contents($dir . 'b_' . basename($urls[$k]), $v);}$timeEnd = microtime(true);echo sprintf("Spend time: %s second(s)\n", $timeEnd - $timeStart);?&gt;

------解决方案--------------------
由于php没有计时器，所以你不可能中断一个没有中断接口的函数的执行
所以底层函数都只适合于理想的条件下

我依然建议你使用多道的curl来完成你的工作

PHP code

$urls = array( 'http://www.jxcms.com/upload/2011/0518/0337319304.jpg', 'http://www.jxcms.com/upload/2011/0310/0951568835.jpg', 'http://www.tzksgs.com/upload/banner1.jpg', 'http://www.tzksgs.com/upload/banner2.jpg');$mh = curl_multi_init();foreach ($urls as $i =&gt; $url) {       $conn[$i] = curl_init($url);       curl_setopt($conn[$i], CURLOPT_RETURNTRANSFER,1);       curl_multi_add_handle($mh, $conn[$i]);}do {  curl_multi_exec($mh, $active);  //在这个循环中，你有机会中断程序的执行。curl_getinfo提供了连接的各种信息}while($active);foreach ($urls as $i =&gt; $url) {  $fn = basename($url);  file_put_contents($fn, curl_multi_getcontent($conn[$i]));  curl_close($conn[$i]);}<div class="clear">




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