#!/usr/bin/perl

use strict;

select(STDIN);$| = 1;
select(STDOUT);$| = 1;
print STDERR "starting interaction\n";
$! = '';

print "GET /\n\n";
print STDERR "printerr is $! " . fileno(STDIN) . ", " . fileno(STDOUT) . "\n";
print STDERR "req sent\n";
$! = '';
while (<STDIN>)
{
        my $v = $_;
print STDERR "readerr is $!\n";
    print STDERR $v;
}
print STDERR "readerr is $!\n";
print STDERR "done interaction\n";
-----------

I tried several versions of servers, and all behave the same:
#------version1 - works fine on linux
#!/usr/bin/perl
use strict;

use IO::Socket;
my $conn = IO::Socket::INET->new(
                        Proto    => "tcp",
                        PeerAddr => "192.168.0.12", #change to any hostname
                        PeerPort => 80,
    ) || die("can't connect");

open(STDIN,"<&" . $conn->fileno);
open(STDOUT,">&" . $conn->fileno);
system("$^X testfile-slave.pl");
print STDERR "done\n";
--------------------

#---------version2 - windows-specific
#!/usr/bin/perl
#use strict;

use IO::Socket;
my $conn = IO::Socket::INET->new(
    Proto    => "tcp",
    PeerAddr => "192.168.0.12", #use address of any web server here
    PeerPort => 80) || die("can't connect");

binmode($conn);
open(STDIN,"<&" . $conn->fileno) || print STDERR "can't redir stdin\n";
open(STDOUT,">&" . $conn->fileno) || print STDERR "can't redir stdout\n";
my $file = "testfile-slave.pl";
use Win32::Process;     use Win32;
my ($ProcessObj,$exitcode);
if (Win32::Process::Create($ProcessObj, "$^X","$^X $file",
                    1, NORMAL_PRIORITY_CLASS,".")) {
                    $ProcessObj->Wait(500000);
                    $ProcessObj->Kill($exitcode);
} else {   print STDERR "failed executing $file\n"; };
print STDERR "done\n";
--------------------