Look for the global array $HTTP_POST_FILES in the manual (Chapter 19. Handling file uploads). It has some cute elements, like:
$target = $HTTP_POST_FILES ['userfile'] ['name'];
$format = $HTTP_POST_FILES ['userfile'] ['type'];
$sizebytes = $HTTP_POST_FILES ['userfile'] ['size'];
The ['name'] element is just what you asked Santa.
Luciano ES
Santos, SP - Brasil