lnmpa下php7 curl不生效

function baidu_check($url) {
    global $wpdb;
    $post_id = (null === $post_id) ? get_the_ID() : $post_id;
    $baidu_record = get_post_meta($post_id, 'baidu_record', true);
    if ($baidu_record != 1) {
        $url = 'http://www.baidu.com/s?wd=' . $url;
        $curl = curl_init();
        curl_setopt($curl, CURLOPT_URL, $url);
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
        $rs = curl_exec($curl);
        curl_close($curl);
         //如果抓取到的百度结果中不存在【提交网址】这个关键词，则认为该页面已被百度收录
        if(!preg_match_all('/提交网址/u',$rs,$matches) && preg_match_all('/百度为您找到相关结果/u',$rs, $matches)){
            update_post_meta($post_id, 'baidu_record', 1) || add_post_meta($post_id, 'baidu_record', 1, true);
            return 1;
        } else {
            return 0;
        }
    } else {
       return 1;
    }
  }
function baidu_record() {
    if (baidu_check(get_permalink()) == 1) {
        echo '<a target="_blank" title="点击查看" rel="external nofollow" href="http://www.baidu.com/s?wd=' . get_the_title() . '">百度已收录</a>';
    } else {
        echo '<a style="color:red;" rel="external nofollow" title="点击提交，谢谢您！" target="_blank" href="http://zhanzhang.baidu.com/sitesubmit/index?sitename=' . get_permalink() . '">百度未收录</a>';
    }
}