---
author: ''
category: ''
date: 2009/12/11 11:04
description: ''
link: ''
priority: ''
slug: BB854
tags: open source, programming, pyqt, python, qt
title: Making a unique application using python and DBUS
type: text
updated: 2009/12/11 11:04
url_type: ''
---
No, not unique in the sense "oh, this app is a special snowflake", but unique in the sense "you can only run one copy of this application".

I tried googling for it and I always found the same answer, "use dbus, try to own the name, if it exists already, then a copy is already running".

What I could not find is one working example of this, or at least not something conveniently labeled "here is how you do a unique application using dbus and python".

So, here is how you do a unique application using dbus and python:

Supposing your application is called uRSSus (mine is):

.. code-block:: python

  session_bus = dbus.SessionBus()
  try:
      session_bus.get_object("org.urssus.service", "/uRSSus")
      # This is the second copy, make the first one show instead
      # TODO: implement
  except dbus.DBusException: # No other copy running
      # This will 'take' the DBUS name
      name = dbus.service.BusName("org.urssus.service", bus=session_bus)
      # Now, start your app:
      window=MainWindow()
      object = UrssusServer(window,name)
      :
      :
      :
      etc, etc      

And that's it. No, it's not hard, but since the DBUS docs seem to be... rather they seem almost *not to be* sometimes, every little bit may help.