This is so off topic, but: Have your friend use Linux!!! (it's only free if your time is worth nothing)
wipe ()
{
for i in "$@";
do
dd if=/dev/urandom of="$i" bs=4096 count=$((`wc -c
<"$i"`/4096+1)) conv=notrunc;
done;
sync;
sync;
chattr +s "$@";
rm "$@";
sync
}
