Re: [Qemu-devel] [PATCH 01/11] QMP: Introduce specification file

[Jamie Lokier <jamie@shareable.org>]

Ian Jackson wrote:
> I think dbus would be a good choice, but even XML-RPC (which, frankly,
> is flabby, overcomplex, slow, hard to read, etc.), JSON (which doesn't
> have an IDL that can even do checking), and ASN.1/DER/BER (which is a
> complexity nightmare) would be an improvement over no automatic
> parsing machinery.

I strongly dislike D-Bus, having been forced to use it to manage Linux
Bluetooth connections.  (The old way with a nice traditional
unix-style executable command to control them was far nicer and
actually worked).

D-Bus is impossible to use properly from shell with the available
shell client (some value types aren't supported), and you have to read
application source code to figure out what calls to use, if the
applications RPCs aren't well documented (which they aren't for Linux
Bluetooth).  There's no useful introspection.

D-Bus seems to be ok for asynchronous notifications, such as what's
used to update icons on a desktop in response to background events.
But it's not at all transactional so you often have temporary
display inconsistencies in a GUI using it.

-- Jamie