#!/usr/bin/env perl

use strict;
use warnings;
use autodie qw{:all};

my $tail_cmd = 'tail -f ./pm_test_file_to_tail';
my @tail_captures;

print '*** Start reading from $tail_pipe at ', time, "\n";
my $tail_pid = open my $tail_pipe, '-|', $tail_cmd;

{
    local $SIG{INT} = sub {
        kill INT => $tail_pid if kill 0 => $tail_pid;
        waitpid $tail_pid => 0;
    };

    while (<$tail_pipe>) {
        push @tail_captures, $_;
    }
}

print '*** Stop reading from $tail_pipe at ', time, "\n";

# Possibly process data captured, e.g. for demo only
$_ = uc for @tail_captures;

print '*** Captured via $tail_pipe:', "\n";
print for @tail_captures;

##</code><code>##

$ cat > pm_test_file_to_tail
line 1
line 2
line 3

##</code><code>##

$ cat >> pm_test_file_to_tail
line 4
line 5

##</code><code>##

$ pm_test_tail_pipe.pl
*** Start reading from $tail_pipe at 1371707519

##</code><code>##

line 6
line 7

##</code><code>##

^C*** Stop reading from $tail_pipe at 1371707542
*** Captured via $tail_pipe:
LINE 1
LINE 2
LINE 3
LINE 4
LINE 5
LINE 6
LINE 7

##</code><code>##

line 8
line 9

##</code><code>##

$ cat pm_test_file_to_tail
line 1
line 2
line 3
line 4
line 5
line 6
line 7
line 8
line 9