#!/usr/bin/perl -w

use strict;
use Gtk2 '-init';
use Gtk2::Helper;
use Data::Dumper;
use IPC::Open2;
use FileHandle;

# file handles
my $wfh = FileHandle->new();
my $rfh = FileHandle->new();
open2($rfh,$wfh, "C:\\Windows\\System32\\cmd.exe");


my $window = Gtk2::Window->new();
$window->signal_connect("destroy",sub{Gtk2->main_quit();});
$window->set_size_request(200,200);
    my $vbox = Gtk2::VBox->new();
    $window->add($vbox);
        my $button = Gtk2::Button->new("WRITE");
        $button->signal_connect('clicked'=>sub{
                write_fh();
            });
        $vbox->pack_start($button,0,0,0);
        $button = Gtk2::Button->new("READ");
        $button->signal_connect('clicked'=>sub{
                read_fh();
            });
        $vbox->pack_start($button,0,0,0);
        
$window->show_all();
Gtk2->main();

sub write_fh {
    print $wfh "dir\n";
}

sub read_fh {
    my $buffer;
    my $resp = sysread($rfh,$buffer,1);
    if($resp){
        if($buffer =~ /\n/){
            print "newline\n";
        }
    }
    print "[$resp]$buffer\n";
}
[download]

Run the program and press the read button until it hangs, it always hangs when it encounters the "end of file" but i think its not the end of file because I am reading the output of the command line. I tried using eof($rfh) and it hangs hehehe... Help please