怎样通过curl上传文件？

<?php

/*

*
*/

set_time_limit(0);

//页面地址

$url2 = ' http://uploadv2.zhuanmi.net:443 /web/upload.do?userid=1381723& maxsize=2147483648& folderid=12218208& key=75463b427ecdf47b2bf01f38e2 467e58';

$name =$_GET["name"];

//$name = urlencode($name);

$post = array(

"excel"=>"@$name",//这里是要上传的文件，key与后台处理文件对应

);

//访问页面2

$ch2=curl_init($url2);

curl_setopt($ch2, 'Mozilla/5.0 (Linux; U; Android 2.3; en-us) AppleWebKit/999  (KHTML, like Gecko) Safari/999.9');

curl_setopt($ch2, CURLOPT_POST, 1);

curl_setopt($ch2, CURLOPT_POSTFIELDS, $post); 

curl_setopt($ch2, CURLOPT_RETURNTRANSFER, true);

curl_setopt($ch2, CURLOPT_REFERER, null);

$content2 = curl_exec($ch2);

curl_close($ch2);

echo $content2; 

//$result = unlink($name); 

?>