Re: [AUCTeX] emacs24 from debian unstable

[Michael Albinus]

Tassilo Horn <address@hidden> writes:

> Hi Andreas,

Hi,

[Please keep me in Cc if you have further questions; I don't read the
auctex ML]

> Michael, what's the proper way to check if DBUS support is available?
> Currently, in AUCTeX I'm using
>
>   (and (not (featurep 'xemacs)) ; XEmacs 21.4 has no `require' with
>                                 ; arity 3, and no dbus support anyway.
>        (require 'dbus nil :no-error)
>        (functionp 'dbus-register-signal)
>        (getenv "DBUS_SESSION_BUS_ADDRESS"))

Whether Emacs has been compiled with D-Bus support, could be checked by
(featurep 'dbusbind). So you could write

  (and (featurep 'dbusbind)
       (require 'dbus nil :no-error)
       (dbus-ignore-errors (dbus-get-unique-name :session)))

`dbus-get-unique-name' is to be preferred over the check of
$DBUS_SESSION_BUS_ADDRESS, because there might be other mechanism
accessing the D-Bus session bus.

The code above shall be backward compatible to Emacs 23 (untested).

> Or maybe it would be better to have a function `dbus-available-p' in
> dbus.el that does whatever checks are needed to determine if DBUS is
> really usable?

That's `dbus-get-unique-name'. If you are interested in a given D-Bus
service, you could apply `dbus-ping' instead, like

       (dbus-ping :session "org.gnome.evince.Daemon" 500)

> Bye,
> Tassilo

Best regards, Michael.