multi curl and single curl

multi_curl.php

<?
set_time_limit(0);
include 'runtime.php';
 
/**
 * 使用多个子连接读同时读取多个连接
 */
function multiCurl($urls)
{
    // 构建 $multi_handle
    $multi_handle=curl_multi_init();
    foreach ($urls as $i => $url)
    {
        $conn[$i]=curl_init($url);
 
        curl_setopt($conn[$i], CURLOPT_RETURNTRANSFER, 1);
        $timeout = 3;
        curl_setopt($conn[$i], CURLOPT_CONNECTTIMEOUT, $timeout);
        curl_setopt($conn[$i], CURLOPT_FOLLOWLOCATION, 1);
        curl_multi_add_handle($multi_handle,$conn[$i]);
    }
 
 
    // 连接，下面这样三个循环的写法可以减少CPU占用
 
    $active = false; // 是否还有子连接在进行中。
    do {
        $mrc = curl_multi_exec($multi_handle,$active); // 运行所有子连接。
    } while ($mrc == CURLM_CALL_MULTI_PERFORM); //当正在接受数据时
 
    while ($active and $mrc == CURLM_OK) {
        if (curl_multi_select($multi_handle) != -1) { // curl_multi_select会一直等待下一个可用连接
            do {
                $mrc = curl_multi_exec($multi_handle, $active);
            } while ($mrc == CURLM_CALL_MULTI_PERFORM);
        }
    }
 
 
    //依次提取连接内容
    foreach ($urls as $i => $url)
    {
        $contents[$i]=curl_multi_getcontent($conn[$i]);
        curl_multi_remove_handle($multi_handle,$conn[$i]);
        curl_close($conn[$i]);
    }
 
    curl_multi_close($multi_handle);
 
    return $contents;
 
}
 
/**
 * 一次只读一个连接
 */
function curl($urls){
 
    foreach($urls as $i => $url){
        $ch = curl_init($url);
 
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        $timeout = 3;
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, $timeout);
        curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
 
        $contents[$i] = curl_exec($ch);
    }
 
    return $contents;
 
}
 
// 测试
 
$runtime = new Runtime;
 
$urls = array(
    'baidu.com',
    'google.com',
    'bing.com',
    'youdao.com',
    'yahoo.com',
);
 
 
echo '<br><br>single connection curl';
$runtime->start();
$resArray = curl($urls);
$runtime->stop();
$runtime->printResult();
 
echo '<br><br>multiple sub connections curl';
$runtime->start();
$resArray = multiCurl($urls);
$runtime->stop();
$runtime->printResult();