prefork echo server

prefork_echo.pl

use strict;
use warnings;

use IO::Socket::INET;
use Parallel::Prefork;

sub MaxRequestsPerChild { 100 };

my $listen = IO::Socket::INET->new(
  Listen    => 5,
  LocalHost => '0.0.0.0',
  LocalPort => '1986',
  Proto     => 'tcp',
) or die $!;

my $pm = Parallel::Prefork->new({
  max_workers  => 5,
  trap_signals => {
    TERM => 'TERM',
    HUP  => 'TERM',
  },
});

while ($pm->signal_received ne 'TERM') {
  $pm->start and next;
  my $reqs_remaining = MaxRequestsPerChild;
  $SIG{TERM} = sub {
    $reqs_remaining = 0;
  };
  while ($reqs_remaining-- > 0) {
    my $s = $listen->accept;
    while (<$s>) {
      print $s $_; # echo back
    }
    close($s);
  }
  close($listen);
  $pm->finish;
}

$pm->wait_all_children;