将卷曲数据发布到另一台服务器

I try to post some data to another server using curl. The problem is that I get nothing on the other server.

Server1:

$a = $USER->id;
$b = $USER->username;

 error_reporting(-1);
    $url = 'http://remote_server/a.php';
$data = array(
   'cus' => $a,
   'cust' => $b
);
    $postString = http_build_query($data, '', '&');
    $ch = curl_init();
    curl_setopt ($ch, CURLOPT_URL, $url);
    curl_setopt ($ch, CURLOPT_POST, 2);
    curl_setopt ($ch, CURLOPT_POSTFIELDS, $postString);
    curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
    $post = curl_exec ($ch);
    curl_close ($ch);

and on Server2:

<?php
session_start();
var_dump($_POST);
?>

Of course it doesn't work, it gives array(0) {}. So, how I will see the data on the other server?

To see the actual output of var_dump($_POST) in Server2, you must either :

• Server1 side : echo $post variable

• Server2 side : write the content of var_dump's result in a file :

  ob_start();
  var_dump($_POST);
  $output = ob_get_clean();
  $fp = fopen('log.txt', 'a');
  fwrite($fp, $output);
  fclose($fp);