open(INPUT,"filename.txt") or die "Will not open input: $!";
open(OUTPUT,">output.txt"); or die "Will not open output: $!";
my $input = <INPUT>;
my $line;
my $i;
my $length = length($input);
for ($i=0; $i<$length; $i=$i+164){
	$line = substr($input,$i,164);
	print "$line\n"; #Output to screen to make sure it works
	print OUTPUT "$line\n";
}