My d-bus doesn't work, or does it?

Nick Gray nagray at
Mon Mar 7 09:41:44 PST 2005

Definitions out of the way, I am using Fedora Core 3 with the following
installed by default:


I get the following from 'ps -ef |grep dbus' 

/usr/bin/dbus-launch --exit-with-session /etc/X11/xinit/Xclients
dbus-daemon-1 --fork --print-pid 8 --print-address 6 --session

and when I try to run the program included, I get this.

org.freedesktop.DBus.Error.FileNotFound: Failed to connect to
socket /usr/local/var/run/dbus/system_bus_socket: No such file or

OK the first question, It looked to me like I was not running a
system_bus, but when I try to start a system bus by hand (using the man
page as a reference) I get another copy of the 'dbus-daemon-1 --fork --
print-pid 8 --print-address 6 --session'. I checked to see that the
file /usr/local/var/run/dbus/system_bus_socket' is actually in place.

Not sure where to go from here.

Here is the demo program that I copied out of LJ. I had to make a few
syntax corrections to the public code, but they were trivial. I am
concerned that the switch still says --session, could this mean that I
am not really getting a system bus running?

Thanks, Nick

Code Example

#include <dbus/dbus.h>
#include <iostream>

int main()
	DBusError error;
	DBusConnection *conn;
	conn = dbus_bus_get(DBUS_BUS_SYSTEM, &error);

	if (!conn)
		fprintf (stderr, "%s: %s\n",, error.message);
		return 1;
	dbus_bus_acquire_service (conn, "org.pirate.parrot", 0, &error);

	if (dbus_error_is_set (&error))
    	fprintf (stderr, "%s: %s\n",, error.message);
    	dbus_connection_disconnect (conn);
    	return 1;
	DBusMessage *msg;
	DBusMessageIter iter;

	/* create a new message of type signal */
	msg = dbus_message_new_signal(
		"org.pirate.parrot.attr", "Feathers");

	/* build the signal's payload up */
	dbus_message_iter_init (msg, &iter);
	dbus_message_iter_append_string (&iter, "Shiny");
	dbus_message_iter_append_string (&iter, "Well Groomed");

	/* send the message */
	if (!dbus_connection_send (conn, msg, NULL))
	fprintf (stderr, "error sending message\n");

	/* drop the reference count on the message */
	dbus_message_unref (msg);

	/* flush the connection buffer */
	dbus_connection_flush (conn);
	if (conn)
        dbus_connection_disconnect (conn);

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