#!/usr/bin/perl

use strict;
use warnings;
use diagnostics;
use IPC::Open3;
use POSIX 'setsid';

sub daemonize {
    chdir '/'               or die "Can't chdir to /: $!";
    open STDIN, '/dev/null' or die "Can't read /dev/null: $!";
    open STDOUT, '>/dev/null' or die "Can't write to /dev/null: $!";
    defined( my $pid = fork ) or die "Can't fork: $!";
    exit if $pid;
    setsid or die "Can't start a new session: $!";
    open STDERR, '>&STDOUT' or die "Can't dup stdout: $!";
}

open( SAVE_STDOUT, ">&", STDOUT )
    or die "save stdout failed";
open( DEVNULL, "< /dev/null" ) 
    or die "open /dev/null failed";

open( FH1, "> /dev/null" ) or die "Open /dev/null failed";

&daemonize( *FH1 );

open3( *DEVNULL, *PIPE, undef, "/bin/sh", "-c", <<EOF );
printf "out 1\\nout 2\\nout 3\\n"
printf "err 1\\nerr 2\\nerr 3\\n" >&2
EOF
;

open( STDOUT, ">&", *SAVE_STDOUT ) or die "restore stdout failed: $!";
while(<PIPE>) {
    print "PIPE: ", $_;
}

close(PIPE) or die "close pipe failed";

exit(1);