use strict;
use warnings;

open my $fh, $0 or die $!;

my @fhs = (\*DATA, $fh);

while (! grep {eof($_)} @fhs) {
	my @lines = map {scalar <$_>} @fhs;
	print for @lines;
}

__DATA__
line1
line2
line3
line4
line5
line6