(PECL pecl_http >= 0.10.0)
HttpRequest::addPostFile — Add post file
$name
   , string $file
   [, string $content_type = "application/x-octetstream"
  ] )Add a file to the POST request, leaving previously set files unchanged.
Affects only POST and custom requests. Cannot be used with raw post data.
name
     the form element name
file
     the path to the file
content_type
     the content type of the file
   Returns TRUE on success, or FALSE if the content type seems not to contain a 
   primary and a secondary content type part.