Re: bonobo activation environment matching and DISPLAY

[Alexander Larsson <alexl redhat com>]

On Tue, 2004-08-24 at 14:17, Mark McLoughlin wrote:
> On Tue, 2004-08-24 at 11:54, Michael Meeks wrote:
> > On Mon, 2004-08-23 at 17:22 +0100, Gustavo J. A. M. Carneiro wrote:
> > > > I assume that your note above about the bonobo:environment property
> > > > doesn't mean that the "artificial environment", i.e. the constructed
> > > > req_env, is deprecated...  let me know if I've missed something.  
> > > 
> > >   Yes, I think it is deprecated, but I defer to Michael on this one. 
> > > Michael, what's your opinion on this?
> > 
> > 	I believe the new idea was to have each .server file denote which bits
> > of the client environment it really cared about; and thus have the
> > server process determining it's own per-display/per-whatever lifecyle
> > rather than the calling-client. That would seem to be a good idea in
> > general - I forget the precise syntatic details, but it focused around a
> > bonobo:environment stringv in the .server file AFAIR.
> 
> 	I think there are few problems here:
> 
>  - The $DISPLAY in the environment isn't canonicalised so comparing 
>    semantically identical $DISPLAY in different process might not match.
> 
>  - The $DISPLAY in the environment doesn't necessarily reflect the 
>    actual display being used - think about --display and --screen.
> 
>  - Merely keying of the $DISPLAY in the environment is not necessarily 
>    always what you want - e.g. if you want per-screen instead of 
>    per-display or vice-versa
> 
> 	So, the old API wasn't perfect - but there were reasons for it. I think
> the main thing we were missing was an easy way of setting DISPLAY with a
> canonicalised value without or without the screen number.

And display canonicalization is very important. Without it you can
easily end up with forkbomb loops.


=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 Alexander Larsson                                            Red Hat, Inc 
                   alexl redhat com    alla lysator liu se 
He's a notorious one-eyed dog-catcher trapped in a world he never made. She's 
a man-hating tempestuous hooker who hides her beauty behind a pair of 
thick-framed spectacles. They fight crime!