dbus - autokey problem

[Dave Kimble]

Thanks for your help.
autokey-gtk sets up hot key combinations and strings to be output when 
the hot key is pressed -
very handy for my email address, website URL, etc.  It loads on user login.

I should just clarify that I have Desktop and Laptop, (Laptop's Lubuntu 
14.04 was cloned from Desktop a while ago).
On Desktop autokey-gtk works, and on Laptop it doesn't.

On boot and login, Laptop's desktop has an untitled window saying :
"Error starting interface. Keyboard monitoring will be disabled. Check 
your system/configuration.
'utf8' codec can't decode byte 0xc0 in position 0: invalid start byte"
Before clearing that window, I have 2 processes called dbus-daemon owned 
by "user" (me),
and 1 process called dbus-daemon owned by root,
and 1 process called dbus-launch owned by me,
and 1 process called autokey-gtk owned by me.

Comparing the two (as best I can) they seem to have exactly the same 
configuration.

Both have /var/run/dbus/system_bus_socket , and /pid which contains nnn, 
which lxtask says is dbus-daemon, Owner = root

$ id -u root
0
$ id -u messagebus
102

I do NOT have /tmp/dbus-* on either Desktop or Laptop, even though 
Desktop has autokey working.
I do not have /run/user/1000/bus

$ dbus-monitor --session
signal sender=org.freedesktop.DBus -> dest=:1.285 serial=2 
path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; 
member=NameAcquired
    string ":1.285"
method call sender=:1.285 -> dest=org.freedesktop.DBus serial=3 
path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
    string "eavesdrop=true,type='method_call'"
method call sender=:1.285 -> dest=org.freedesktop.DBus serial=4 
path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
    string "eavesdrop=true,type='method_return'"
method call sender=:1.285 -> dest=org.freedesktop.DBus serial=5 
path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
    string "eavesdrop=true,type='error'"
signal sender=:1.31 -> dest=(null destination) serial=1741 path=/; 
interface=org.kde.KDirNotify; member=leftDirectory
    string "file:///tmp"
^C

Sorry that is all such a mess, but I am thoroughly confused.
Is it possible to remove dbus and re-install it?
Looking forward to installing Lubuntu 16.04 next month.

On 25/03/16 22:45, Simon McVittie wrote:
> On 23/03/16 03:54, Dave Kimble wrote:
>> I suspect something is not right with the way my dbus is set up.
>> I have dbus-daemon (root) and dbus-daemon (user) and dbus-launch (user)
>> running.
> What you should normally have is:
>
> * a /system bus/ (dbus-daemon instance with --system in argv), running
>    as uid "messagebus" or "dbus" or similar, and listening on
>    /var/run/dbus/system_bus_socket
>
> * a /session bus/ (dbus-daemon instance with --session in argv) per
>    login session, running as the uid you used to log in, and listening
>    on some abstract Unix socket usually starting with /tmp/dbus- (it
>    will be different for every session). In newer distributions this
>    sometimes listens on a real (path-based) Unix socket
>    /run/user/${uid}/bus instead, but Ubuntu 14.04 is too old for that
>    to be relevant.
>
> * (usually) a dbus-launch process per login session, running as the uid
>    you used to log in, which is responsible for starting the dbus-daemon
>    (in newer distributions where /run/user/${uid}/bus is used, this is
>    not necessary and it's OK for it to be absent)
>
> If you have a dbus-daemon instance whose uid is root, something has
> probably gone wrong somewhere.
>
> I have no idea what autokey-gtk is for, but it has gtk in its name, so
> I'm assuming it's meant to run within the scope of the X11 login
> session, with the same uid as the login session itself, and connect to
> the session bus. That would mean it's broadly equivalent to the
> behaviour of things like GNOME Online Accounts, Telepathy, dconf, etc.
> Please correct those assumptions if any of them are wrong.
>
> Within each login session, the environment variable
> DBUS_SESSION_BUS_ADDRESS will be set to something like
> unix:abstract=/tmp/dbus-39863tnm. That path does not actually exist in
> the filesystem, and that's OK: it is said to be an /abstract Unix socket/.
>
> You should be able to run "dbus-monitor --session", or the d-feet, qdbus
> or gdbus tools, and have them connect to the session bus. If using
> dbus-monitor or another monitor-style tool, press Ctrl+C to terminate it.
>
>> I am trying to debug a situation where autokey-gtk launches and tries
>> to connect to dbus and gets a warning that /tmp/dbus-* does not exist.
> Please paste a specific, searchable warning: literal text is more useful
> than paraphrasing. You can censor it if you need to, e.g. replacing
> usernames with alice/bob, as long as you're consistent about it.
>