#!/usr/bin/perl

# http://perlmonks.org/?node_id=1206479

use strict;
use warnings;

pipe (my $reader, my $writer);  
$writer->autoflush(1);   

my $parent=$$;
print "parent: $parent\n";

for (0..2) # Forking children
  {
  defined fork or die "Cant fork: $!";
  }

if($$ == $parent) # Master process
  {
  close $writer;        
  print "parent $$\n";
  while (1)
    {
    my $line = <$reader>;
    print "<<<<<<<<<<<<<<<<<<< $line";
    } 
  }
else # Fork process
  {
  close $reader;
  while(1)
    {
    print "\tchild ", $$ - $parent, "\n";
    print $writer $$ - $parent, "\n";
    sleep 1;
    }
  exit 0;
  }