## Owning bus names

Using dbus-glib, you typically call RequestName manually to own a name, like in the following excerpt:

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    error = NULL;
      res = dbus_g_proxy_call (system_bus_proxy,
                               "RequestName",
                               &error,
                               G_TYPE_STRING, NAME_TO_CLAIM,
                               G_TYPE_UINT,   DBUS_NAME_FLAG_ALLOW_REPLACEMENT,
                               G_TYPE_INVALID,
                               G_TYPE_UINT,   &result,
                               G_TYPE_INVALID);
      if (!res)
        {
          if (error != NULL)
            {
              g_warning ("Failed to acquire %s: %s",
                         NAME_TO_CLAIM, error->message);
              g_error_free (error);
            }
          else
            {
              g_warning ("Failed to acquire %s", NAME_TO_CLAIM);
            }
          goto out;
        }

      if (result != DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER)
        {
          if (error != NULL)
            {
              g_warning ("Failed to acquire %s: %s",
                         NAME_TO_CLAIM, error->message);
              g_error_free (error);
            }
          else
            {
              g_warning ("Failed to acquire %s", NAME_TO_CLAIM);
            }
          exit (1);
        }

      dbus_g_proxy_add_signal (system_bus_proxy, "NameLost",
                               G_TYPE_STRING, G_TYPE_INVALID);
      dbus_g_proxy_connect_signal (system_bus_proxy, "NameLost",
                                   G_CALLBACK (on_name_lost), NULL, NULL);

      /* further setup ... */

While you can do things this way with GDBus too, using `g_dbus_proxy_call_sync()`, it is much nicer to use the high-level API for this:

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    static void
    on_name_acquired (GDBusConnection *connection,
                      const gchar     *name,
                      gpointer         user_data)
    {
      /* further setup ... */
    }

    /* ... */

      owner_id = g_bus_own_name (G_BUS_TYPE_SYSTEM,
                                 NAME_TO_CLAIM,
                                 G_BUS_NAME_OWNER_FLAGS_ALLOW_REPLACEMENT,
                                 on_bus_acquired,
                                 on_name_acquired,
                                 on_name_lost,
                                 NULL,
                                 NULL);

      g_main_loop_run (loop);

      g_bus_unown_name (owner_id);

Note that `g_bus_own_name()` works asynchronously and requires you to enter your mainloop to await the `on_name_aquired()` callback. Also note that in order to avoid race conditions (e.g. when your service is activated by a method call), you have to export your manager object before acquiring the name. The `on_bus_acquired()` callback is the right place to do such preparations.