#!/usr/bin/perl

use strict; # https://perlmonks.org/?node_id=11107627
use warnings;
use IO::Socket;
use Forking::Amazing;

my $maxforks = 20;                 # tune these ...
my $clientsperchild = 300;
my $port = 6666;

my $listen = IO::Socket::INET->new(LocalPort => $port,
  Listen => 20, Reuse => 1) or die "$@ on listen create";

Forking::Amazing::run
  $maxforks,
  sub
    {
    print "child $$\n";
    process( scalar $listen->accept or return [] ) for 1 .. $clientsperchild;
    return [];
    },
  sub { push @Forking::Amazing::ids, 1 },
  (1) x $maxforks;

sub process                                         # custom code  goes in here
  {
  my $socket = shift;
  my $query = <$socket> // return [];               # read query
  print $socket "prefork $$ is answering: $query";  # reply
  }