GtkApplicationCommandLine throws GDBus.Error:org.freedesktop.DBus.Error.NoReply

[J Phani Mahesh <phanimahesh ee510 ee iitd ac in>]

Hi all!

I use python primarily and was trying to use GtkApplication for one of
my applications. However, the simplest one fails. The following code
shows a window when run, when a different instance is started, the
existing window gets focus, but when the window is closed, the second
instance throws

GDBus.Error:org.freedesktop.DBus.Error.NoReply

I have been scratching my head since the past week to find its cause.
Any amount of Googlefu did not help.

I finally figured that command line is a method call message that is
sent over Dbus and the second instance expects a reply. (looks like all
method call messages expect a reply) When I monitor dbus I see that
there is no reply indeed. Please assist me with this.

Also, I would like the client instance to quit after printing a message
if there is a primary instance. I can print the message but couldn't
find a way to quit only the second instance. Any thoughts?

# Python3 code

import sys
from gi.repository import Gio, Gtk

def on_command_line(application, command_line):
    windows = application.get_windows()
    if len(windows):
        windows[0].present()
    else:
        window = Gtk.ApplicationWindow(application=application)
        window.show()
# Print a message.
    if command_line.get_is_remote():
        command_line.do_print_literal("Another instance is running.")
# Gtk complains if I don't return a value.
    return 0

application = Gtk.Application(
                        application_id='org.gnome.test',
                        flags=Gio.ApplicationFlags.HANDLES_COMMAND_LINE
                        )

application.connect('command-line', on_command_line)
application.run(sys.argv)
-- 
J Phani Mahesh
( http://phanimahesh.wordpress.com )

You deserve something amazing and free from restriction, you
deserve free software.(free not as in free beer but as in free speech)

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