premature cp exit?

[Try KDE <trykde@rogers.com>]

Hi,

I've just observed something interesting on my PC. My machine is a 
AMD1800+ with 1GB RAM, kernel 2.4.18.  I have a floppy disk:
   $ mkdosfs /dev/fd0 1440
   $ mount /mnt/floppy
   $ cp some-big-fie  /mnt/floppy

What I found is that cp returns immediately, and the floppy drive's LED 
doesn't turn off until 5-10 seconds later. It seems to me that cp copied 
the content to kernel and returned without it being committed to the 
physical media. This could be a wrong behavior considering that a bad 
media may later fail the operation. What do you guys think about it? Is 
there an option or something to force cp to wait?

Thanks,
-tk.