User aborting a download and counting the filesize the website transfered.

Is it possible to let a user download a file from your website but if he cancel's it the script's gets aborted or call's another function instead going on. I am asking this because i want to record downloaded filesize statistics and i need to know if a transfer is succeeded or aborted. It would even be nice if i could record the downloade filesize of the part the user downloaded from my web even if he didn't finished the download. Danny Roelofs The Netherlands [againstspam] droelofs@home.nl