On Friday 30 March 2007 20:04:47 Lubos Lunak wrote:
> On st 28. března 2007, David Jarvie wrote:
> > I want to implement a kded module to read system time zone information,
> > as was previously suggested on this list.
>
>  That's http://lists.kde.org/?l=kde-core-devel&m=115884044529385&w=2 , for
> those who don't remember anymore.

Yes, I'd forgotten it was your suggestion. :(

> > - Where/how should the kded module store the data it reads? It needs to
> > be accessible via KSystemTimeZone. The data is basically fixed - any
> > changes would be very infrequent - should it be stored in ksycoca?
>
>  IIRC the data to store are the name of the local zone and some info about
> each timezone, right? The local zone name can go e.g. in kdeglobals or a
> separate config file (together with some timestamp(s) for avoiding doing
> anything when nothing has changed).
>
>  As for storing timezone data, I suppose that's up to you :) and it
> probably depends on the data you want to store. If everything from
> /usr/share/zoneinfo is needed (that's 900k here :-/ ) and you want to do it
> a simple way, then I have a class for writing a complete directory
> structure into a single file and classes for accessing them
> (QDir::entryList()-like listing and a function returning contents as
> QByteArray) - it's for Qt3/KDE3 now though.

The only data which needs to be cached is the local zone identity and on 
Solaris the time zone index data equivalent to zone.tab. I don't think that 
there's any need to cache zoneinfo data other than avoiding reading it more 
often than necessary during a session.

> > - On some systems, a parsed copy of one of the system time zone files
> > should ideally be stored in the system-wide KDE data directory so as to
> > avoid having to re-parse the system file at session start. How can the
> > location of this directory be accessed? KStandardDirs doesn't seem to
> > provide this information except as one in a list of data directories,
> > which is ambiguous.
>
>  System-wide may be a bit problematic because of access rights and such
> stuff. Maybe there could be a setuid (setuid nobody?) helper that'd create
> the file, not that I'm really an expert on such things.
>
>  For storing it per-user it'd be the "cache" KStandardDirs resource.

I suppose doing it once per user isn't too much of an overhead.

Thanks for your help in answering these questions. :)

-- 
David Jarvie.
KAlarm author and maintainer.
http://www.astrojar.org.uk/kalarm