SSL certificate problem: unable

PHP 通过 curl 访问 https 时出现 SSL certificate problem: unable to get local issuer certificate 的解决方法：只要设置以下两个属性就可以解决。
将 CURLOPT_SSL_VERIFYPEER 设置为 false,
将 CURLOPT_SSL_VERIFYHOST 设置为 false.
代码如下：
<?php
$curl = curl_init();
$url  = 'https://www.baidu.com/';
curl_setopt_array(
        $curl,
        array(
                CURLOPT_URL => $url,        
                CURLOPT_REFERER => $url,
                CURLOPT_AUTOREFERER => true,
                CURLOPT_RETURNTRANSFER => true,
                CURLOPT_SSL_VERIFYPEER => false,
                CURLOPT_SSL_VERIFYHOST => false,
                CURLOPT_CONNECTTIMEOUT => 1,
                CURLOPT_TIMEOUT => 30,
                CURLOPT_USERAGENT => 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/34.0.1847.116 Safari/537.36'
        )
);
//其他代码...
?>