According to me, the simplest way is to abstract the operation of "reading a chunk of data" in a procedure, like in this example: 
use strict;
use warnings;

while ( my @s = read_chunk() )
{
    print join " | ", @s;
    print "\n";
}

sub read_chunk
{
    my @stuff = ();
    while( my $line = <DATA> ) {
        chomp $line;
        push @stuff, $line;
        last if $. % 4 == 0;
    }
    return @stuff;
}

__DATA__
first1
second1
third1
fourth1
first2
second2
third2
fourth2
first3
second3

[download]
So you can treat a read_chunk() operation as an atomic one.

A more clever option you could explore is using Tie::File, which allows you to manipulate the file as an array of lines, even if simgle lines are actually read only when they're needed (details on the documentation).

In reply to Re: Read File In Four-Line Chunks / TMTOWTDI / Golf by larsen
in thread Read File In Four-Line Chunks / TMTOWTDI / Golf by Cody Pendant

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