Select Code to Download

use strict;
use warnings;
...
    # qx( 'cp' $fullpath $fullpath'.bkup');
    # to back up files before proceeding.
}

my $start_date = $ARGV[0] || 'bogus';
die "bad argument" unless $start_date =~ /\d{8}/;
my $end_date = $ARGV[1] || 'bogus';
die "bad argument" unless $end_date =~ /\d{8}/;
...

    next if $file > $end_date;
    last if $file < $start_date;
    ...