>Ah! Sorry, I missed that :- /

No problem at all... ;-)

I just wanted to point you to the possibility that unpack can process many lines at the same time, (which essentially means "reading vertically").

use strict;
use warnings;

my $line_count = 10;

my $line = join ("", 'a'..'z',"A".."Z") . "\n";

my $file= "$line" x $line_count;



my $offset = 2;
my $rest   = length($line) - $offset -1;


my $fmt = qq{(x${offset}ax${rest})${line_count}};

my @results = unpack $fmt, $file;

print @results;

[download]

Will print cccccccccc because of offset 2

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re^4: Faster and more efficient way to read a file vertically by LanX
in thread Faster and more efficient way to read a file vertically by Anonymous Monk

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