use Tie::File;
use strict;
use warnings;

my @files_as_arrays = map {
    my @a;
    tie @a, 'Tie::File', $_;
    \@a
} @ARGV;

{
    local( $,, $\ ) = ( "\t", "\n" );
    my $i = 0;
    while (1) {
        my @a = map { $_->[$i] } @files_as_arrays;
        $i++;
        grep { defined $_ } @a or last;
        no warnings;
        print @a
    }
}

##</code><code>##

use IO::File;
use strict;
use warnings;

my @filehandles = map { new IO::File $_, 'r' } @ARGV;

while (1)
{
    my @a = map { $_->getline } @filehandles;
    grep { defined $_ } @a or last;
    no warnings;
    print join( "\t", @a ), "\n";
}