php服务端如何响应post请求？

<?php
// 建立连接
$curl = curl_init();
//设置
$url = &#39;localhost&#39;;
curl_setopt($curl, CURLOPT_URL, $url);
# 设置开启post请求
curl_setopt($curl, CURLOPT_POST, $url);
$post_data = array(
    &#39;user_name&#39; => &#39;admin&#39;,
    &#39;user_pwd&#39; => &#39;123456&#39;
    );
curl_setopt($curl, CURLOPT_POSTFIELDS, $post_data);
//发送
var_dump(curl_exec($curl));
//关闭
curl_close($curl);

curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);

$post_data = array('image' => '@c:/1.jpg');

curl_setopt($curl, CURLOPT_COOKIEFILE, true);
curl_setopt($curl, CURLOPT_HEADER, 'c:/cookie.txt');

curl_setopt($curl, CURLOPT_HEADER, true);

header('Expires: ' . gmdate('D, d M Y H:i:s', time()+5) . ' GMT');

self";