tracking the download of a file

["Mark W. Webb" <ma...@dolphtech.com>]

I am working on a program that checks the file download progress and 
audits the results.  I have noticed with netscape browsers, that if a 
user starts downloading a file, and the "Save As" window comes up, there 
is a small amount ~200K worth of data that gets written to the browser. 

Is there a way to prevent this?  Because if the file is small, less than 
100K, I do not know if the user actually downloaded the entire file, or 
if they just cancelled the download.

thanks in advance