Getting uploaded filename & directory

In setting up a form to allow a user to upload a file, upon submission of that form, you can get the actual file name that is being uploaded by accessing the variable: $userfile_name (assuming the form element's name where the user specifies the file is "$userfile"). Is there a way to get the full path as well? ie: "c:\program files\this directory\uploaded_file.txt" ? I tried echoing out $userfile to no avail. I also tried some javascript that when the form was submitted, the value for the userfile element was copied to a hidden form element, but that didn't work either. Any ideas? Suggestions? Chris