#!/usr/bin/perl

my @array = (
    'nfs,7,rw',
    'afp,12,rro',
    'cifs,32,ro',
    'dns,5,rw',
);

my @cols;
for my $row (@array) {
    my $i = 0;
    push @{$cols[$i++]}, $_ for split /,/, $row;
}

use Data::Dumper;
print Dumper(\@cols);