Someone

  def buttonClick(self, code):
    code_process = popen2.Popen4(code)
    mencoder_process = gobject.io_add_watch(code_process.fromchild, gobject.IO_IN, self.sucess_dialog, code_process.pid)

     
  #------------------------------------#
  def stop_capture(self, widget, pid):
    os.kill(pid, 9)
    print pid
    pass
  def sucess_dialog(self, a, b, pid):
    print b, pid
    sucess_dialog = gtk.MessageDialog(None, 0, gtk.MESSAGE_WARNING, gtk.BUTTONS_OK, "Video capturado com sucesso!")
    sucess_dialog.run()
    sucess_dialog.connect("destroy", self.stop_capture, pid) 
    sucess_dialog.destroy()