format STDOUT_TOP = 
...
...
[download]

Interesting, I didn't know you could do this with perl. This is all called when write is called?

The two other things that jumped out at me:

Why not $list{$cust}{$money} += $amount instead of $list{$cust}->{$money} += $amount? The -> isn't really necessary.

Where you you compute $list{$cust}->{prior}? I don't see it anywhere else in the code, save the place where you try to print it.

Update: Oh, I'm an idiot. $money is set to prior by the function call. /me slaps forehead and slinks away....

Cheers,
ibanix

$ echo '$0 & $0 &' > foo; chmod a+x foo; foo;