#!/usr/bin/perl -w
use strict;

sub fixedsplit {
    my ($data,$len) = @_;
    ($data =~ /(.{1,$len})/g);
}

my $data = "abcdefghijklmnopqrstuvwxyz";
my @fields;

@fields = fixedsplit($data,4);
print "@fields\n";
@fields = fixedsplit($data,6);
print "@fields\n";