Re: [systemd-devel] Specifying calendar events in an arbitrary timezone
Ah, systemd in fact had tzdata parsing code already – it was used by tinedatectl to show DST info. Try to recover it from Git. On Thu, Dec 15, 2016, 21:03 Ran Benita wrote: > On Thu, Dec 15, 2016 at 06:35:15PM +0100, Lennart Poettering wrote: > > So yeah, we'd love to support this, but are waiting for a suitable API. > > I see, makes sense. > > Since new glibc API will probably be slow to come, if ever, it might > make sense to circumvent it and go for the tzdata directly? It seems the > format is described in tzfile(5), and the glibc code which handles it > seems to be public domain as well: https://github.com/eggert/tz > I don't have any experience with those APIs, though. > > If I get some time I'll try and see if such an approach is viable. > > Thanks! > ___ > systemd-devel mailing list > systemd-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/systemd-devel > -- Mantas Mikulėnas Sent from my phone ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] Specifying calendar events in an arbitrary timezone
On Thu, Dec 15, 2016 at 06:35:15PM +0100, Lennart Poettering wrote: > So yeah, we'd love to support this, but are waiting for a suitable API. I see, makes sense. Since new glibc API will probably be slow to come, if ever, it might make sense to circumvent it and go for the tzdata directly? It seems the format is described in tzfile(5), and the glibc code which handles it seems to be public domain as well: https://github.com/eggert/tz I don't have any experience with those APIs, though. If I get some time I'll try and see if such an approach is viable. Thanks! ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] Specifying calendar events in an arbitrary timezone
On Thu, 15.12.16 17:52, Ran Benita (ran...@gmail.com) wrote: > My question: is this not supported on purpose (because timezones suck), > or because it's just not implemented/hard to implement? Current systemd actually supports calendar events with timezone specifications. However, the specified time zone must either be "UTC" or identical to the one configured in /etc/localtime, which doesn't make it particularly useful I guess (the reason we support this is so that any timestamp we spit out can also be parsed againt as calendar event specification, and out timestamps after all do include a timezone specification). We'd love to support any kind of timezone specifications, but glibc does not offer a suitable API for that. We could change around the $TZ env var all the time when doing time calculations, but that's just awful. For most locale-dependent function calls glibc nowadays provides "locale_t" arguments in order to run them with a different locale. It would be great if it had a matching "timezone_t" type or so which would allow running time-specific functions with a different timezone. So yeah, we'd love to support this, but are waiting for a suitable API. Lennart -- Lennart Poettering, Red Hat ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
[systemd-devel] Specifying calendar events in an arbitrary timezone
I would like to schedule some timers to execute daily at a given time in some given timezone. My use-case for this is: - The server's local timezone is UTC - this is just good practice for various reasons, so I don't want to change that. - For business reasons, the service I want to run needs to run at the given time in the given timezone. Since that timezone switches daylight saving twice a year, I cannot specify the time in UTC, since it will become 1 hour off when the local time changes. systemd does not allow to specify a calendar event in a non-local, non-UTC timezone. This is explictly specified in systemd.time(7): Non-local timezones except for UTC are not supported. My question: is this not supported on purpose (because timezones suck), or because it's just not implemented/hard to implement? If it's on purpose, I can relate - in a local timezone, the event can occur 0, 1 or 2 times, which is not good. However, since systemd already supports the local timezone, I think this battle is already lost. So we can say that the behavior for an arbitrary timezone is the same as if it were the local timezone. ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
