HTTP PUT到PHP中的唯一文件名

I would like to use HTTP to transfer a file to a webserver and save it with a meaningful filename. I currently have the transfer part working, I need to make the meaningful filename piece work.

If I use Curl to transfer the file, I specify which file to send:

curl -X PUT http://user:passwd@x.x.46.9/put.php --data-binary "session"

The PHP script on the webserver is as follows:

/* PUT data comes in on the stdin stream */
$putdata = fopen("php://input", "r");

/* Open a file for writing */
 $fp = fopen("myputfile.ext", "w"); 

/* Read the data 1 KB at a time
   and write to the file */
while ($data = fread($putdata, 1024))
  fwrite($fp, $data);

/* Close the streams */
fclose($fp);
fclose($putdata);
?>

Is there a way to extract the filename sent in the HTTP PUT message and use this for the filename? Or, at the very least, is there a way to save the file using the IP address of the source device?

Much obliged.

Yes, you have all that information in the $_REQUEST variable.