transfer file using file_get_content
$filename = "/path/to/uploaded/file.zip";
$file_contents = file_get_contents($filename);
$content = "--".MULTIPART_BOUNDARY."rn".
"Content-Disposition: form-data; name="".FORM_FIELD.""; filename="".basename($filename).""rn".
"Content-Type: application/ziprnrn".
$file_contents."rn";
// add some POST fields to the request too: $_POST['foo'] = 'bar'
$content .= "--".MULTIPART_BOUNDARY."rn".
"Content-Disposition: form-data; name="foo"rnrn".
"barrn";
// signal end of request (note the trailing "--")
$content .= "--".MULTIPART_BOUNDARY."--rn";