#!/usr/bin/env perl
use strict;
use warnings;

use IO::Socket::INET;
use Fcntl;

my $socket = IO::Socket::INET->new(
	LocalAddr => "127.0.0.1:0",
	Listen => 1
);

sysopen(my $fh, $ARGV[0], O_WRONLY|O_CREAT|O_EXCL, 0666) or die "open: $ARGV[0]: $!";
my $pid = fork();
if ($pid > 0) {
	print $fh $pid;
	print $socket->sockport()."\n";
	exit;
}
close($fh);
open(STDIN, '</dev/null');
open(STDOUT, '</dev/null');

my @cmd = @ARGV;
shift @cmd;

while (1) {
	my $conn = $socket->accept();
	my $worker = fork();
	if ($worker == 0) {
		open(STDIN, '<&', $conn);
		open(STDOUT, '>&', $conn);
		close($conn);
		close($socket);
		exec @cmd;
		exit
	}
	close($conn);
}