use strict;
use warnings;

##</code><code>##

my @DATA=<ORIGFILE>;

##</code><code>##

while (my $line=<ORIGFILE>) { # ...

##</code><code>##

open my $in, '<', "whatever" or die "can't open `whatever': $!\n";
open my $out, '>', "whatever" or die "can't open `whatever': $!\n";