PHP 批量获取 百度搜索结果 网址列表

<?php
set_time_limit(0);

function curl($url){
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_TIMEOUT, 5);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HEADER, 0);
    $data = curl_exec($ch);
    curl_close($ch);
    return $data;
}

function baidu_site_url($wd, $pn){

    $html = curl('http://www.baidu.com/s?wd='.urlencode($wd).'&pn='.$pn);
    preg_match_all('/<span class="g">([^\/]*)\//', $html, $matches);
    return $matches[1];
}

if (!empty($_GET['page']) && !empty($_GET['wd'])){//获取到第几页, 关键词

    $page = $_GET['page'];
    $wd = $_GET['wd'];
    $handle = fopen('url.txt', 'a');

    for ( $i = 0 ; $i < $page ; $i++ ) {

        $tmp = baidu_site_url($wd, $i*10);
        foreach ($tmp as $v){
            fwrite($handle, $v."\r");
        }
    }

    fclose($handle);

}else{

    exit;
}

?>