title: How to forward multipart/form-data body of request using a php proxy
body: <p>I want to use a php proxy to resolve the cross domain problem during uploading file.
  In the script i used php curl to forward request and response, but i don't know how to forward the request body  to the server when the request body is multipart/format-data. 
  <strong>file_get_contents('php://input')</strong> will be null when the Content-Type header is "multipart/form-data". 
  And when using <strong>curl_setopt( $ch, CURLOPT_POSTFIELDS, $_POST)</strong>, the Content-Disposition in request body could be sent, while the real data of file could not.</p>
  
  <p>My request body is like this: </p>
  
  <pre><code>------WebKitFormBoundaryd0tvwIvevPV4VTlP
  Content-Disposition: form-data; name="name"
  
  nbzdds.mp3
  ------WebKitFormBoundaryd0tvwIvevPV4VTlP
  Content-Disposition: form-data; name="chunk"
  
  15
  ------WebKitFormBoundaryd0tvwIvevPV4VTlP
  Content-Disposition: form-data; name="chunks"
  
  44
  
  497161
  ------WebKitFormBoundaryd0tvwIvevPV4VTlP
  Content-Disposition: form-data; name="file"; filename="blob"
  Content-Type: application/octet-stream
  
  ��v\;"S�;-�mG\u#...
  .
  .
  .
  </code></pre>