Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.debian.user > #270289

Re: System time/timezone, was Re: Maximum size .bash_aliases file

From Jeffrey Walton <noloader@gmail.com>
Newsgroups linux.debian.user
Subject Re: System time/timezone, was Re: Maximum size .bash_aliases file
Date 2024-06-20 07:30 +0200
Message-ID <IRiwV-4dgZ-1@gated-at.bofh.it> (permalink)
References (6 earlier) <IQESR-3NjL-1@gated-at.bofh.it> <IQUNX-3WZK-1@gated-at.bofh.it> <IR1mp-410r-3@gated-at.bofh.it> <IR6YO-45Ug-9@gated-at.bofh.it> <IRi3U-4cQA-5@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw

On Thu, Jun 20, 2024 at 12:52 AM <tomas@tuxteam.de> wrote:
>
> On Wed, Jun 19, 2024 at 01:01:44PM -0400, Jeffrey Walton wrote:
> > On Wed, Jun 19, 2024 at 7:09 AM Greg Wooledge <greg@wooledge.org> wrote:
>
> [...]
>
> > > I strongly disagree.  The system clock is kept on "epoch time", which
> > > is the number of seconds since midnight, January 1, 1970 UTC.
> > >
> > > The system clock doesn't have a time zone of its own.  It just gets
> > > converted to a time and date within any given time zone on demand.
> >
> > ++.
> >
> > The sharp edge is how the RTC clock is set - UTC or localtime. Also
> > see <https://wiki.debian.org/DateTime>.
>
> Please don't mix those three things, that makes them just more confusing.
>
> The original topic was the system's time zone. This hasn't anything
> to do with the RTC clock, and only peripherally with "the system's
> time zone" (of which some, me included, say "there's no such thing",
> and others disagree :)
>
> You have
>
>  - the RTC clock. This is *only* looked at at boot time, to init
>    the system clock (and when you, as an admin, do "hwclock").
>    During those operations, it's important to know which timezone
>    the RTC is in, since this one /is/ in "human format. It was
>    intended to be read and set by humans, like your kitchen clock,
>    back then.
>
>  - the system clock: it boringly counts seconds. Since Epoch.
>    Since it has't hours or minutes, let alone weeks or months,
>    time zones don't even make sense to it. Sometimes it does
>    a leap second, but experts are torn on whether this was a
>    good idea at all. Have a look at [1] for an entrance to yet
>    another deep time rabbit hole.
>
>  - timezones and stuff: those happen whenever you want to convert
>    the system clock to hours, minutes, days, and other human
>    related stuff and back.
>
> (if you have good net connectivity, reading the RTC at boot can
> be shunned completely, you don't need it anymore).

Don't forget boottime and the delta between boottime and the monotonic
clock. You'll need them to explain this:

$ TZ=America/New_York dmesg -T | head -1
[Wed Jun 19 01:50:14 2024] Linux version 6.9.4-200.fc40.x86_64 (mockbuild@d372fa
1a67e347178b7bd422ead09b96) (gcc (GCC) 14.1.1 20240607 (Red Hat 14.1.1-5), GNU l
d version 2.41-37.fc40) #1 SMP PREEMPT_DYNAMIC Wed Jun 12 13:33:34 UTC 2024

$ TZ=America/California dmesg -T | head -1
[Wed Jun 19 05:50:14 2024] Linux version 6.9.4-200.fc40.x86_64 (mockbuild@d372fa
1a67e347178b7bd422ead09b96) (gcc (GCC) 14.1.1 20240607 (Red Hat 14.1.1-5), GNU l
d version 2.41-37.fc40) #1 SMP PREEMPT_DYNAMIC Wed Jun 12 13:33:34 UTC 2024

> Please, keep those three at a safe distance

I'm not sure how you can disgorge them given they contribute to a
human readable time.

Jeff

Back to linux.debian.user | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-16 10:20 +0200
  Re: Maximum size .bash_aliases file Richard <rrosner5@gmail.com> - 2024-06-16 15:30 +0200
    Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-17 10:50 +0200
  Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-16 16:00 +0200
    Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-17 10:30 +0200
      Re: Maximum size .bash_aliases file gene heskett <gheskett@shentel.net> - 2024-06-17 13:00 +0200
      Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-17 13:30 +0200
        Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-18 10:30 +0200
          Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-18 13:10 +0200
            Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-22 10:00 +0200
      Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-17 16:20 +0200
        Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-17 16:30 +0200
          Time, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-17 17:40 +0200
            Re: Time, was Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-17 17:50 +0200
            Re: Time, was Re: Maximum size .bash_aliases file eben@gmx.us - 2024-06-17 19:30 +0200
              Re: Time, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-22 10:10 +0200
            Re: Time, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-22 10:10 +0200
        Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-17 18:30 +0200
          Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-17 19:30 +0200
            Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-17 19:50 +0200
              System time/timezone, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-18 07:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-18 10:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Jeffrey Walton <noloader@gmail.com> - 2024-06-18 10:20 +0200
                RTC, was Re: System time/timezone David Wright <deblis@lionunicorn.co.uk> - 2024-06-19 06:10 +0200
                Re: RTC, was Re: System time/timezone Nicholas Geovanis <nickgeovanis@gmail.com> - 2024-06-19 21:20 +0200
                Re: RTC, was Re: System time/timezone Greg Wooledge <greg@wooledge.org> - 2024-06-19 21:40 +0200
                Re: RTC, was Re: System time/timezone Stefan Monnier <monnier@iro.umontreal.ca> - 2024-06-20 04:00 +0200
                Re: RTC, was Re: System time/timezone Max Nikulin <manikulin@gmail.com> - 2024-06-20 04:00 +0200
                Re: RTC, was Re: System time/timezone Keith Bainbridge <keithrbau@gmail.com> - 2024-06-22 10:20 +0200
                Re: RTC, was Re: System time/timezone Michael Stone <mstone@debian.org> - 2024-06-20 05:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-19 06:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-19 06:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-18 13:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-19 06:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-19 13:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Jeffrey Walton <noloader@gmail.com> - 2024-06-19 19:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-20 07:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Jeffrey Walton <noloader@gmail.com> - 2024-06-20 07:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file tomas@tuxteam.de - 2024-06-20 08:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Max Nikulin <manikulin@gmail.com> - 2024-06-21 04:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-21 05:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-21 06:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-22 17:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Stefan Monnier <monnier@iro.umontreal.ca> - 2024-06-22 18:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Nicholas Geovanis <nickgeovanis@gmail.com> - 2024-06-23 04:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-23 05:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-23 06:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-23 07:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file gene heskett <gheskett@shentel.net> - 2024-06-23 08:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file eben@gmx.us - 2024-06-23 15:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file gene heskett <gheskett@shentel.net> - 2024-06-23 16:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-26 02:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file eben@gmx.us - 2024-06-26 15:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Curt <curty@free.fr> - 2024-06-24 15:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Curt <curty@free.fr> - 2024-06-24 15:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Bret Busby <bret@busby.net> - 2024-06-24 17:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Heriberto Avelino <heriberto.avelino@gmail.com> - 2024-06-26 00:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Bret Busby <bret@busby.net> - 2024-06-24 17:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file eben@gmx.us - 2024-06-24 18:10 +0200
                Re: System time/timezone Felix Miata <mrmazda@earthlink.net> - 2024-06-24 18:20 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file The Wanderer <wanderer@fastmail.fm> - 2024-06-25 00:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file John Hasler <john@sugarbit.com> - 2024-06-25 00:20 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file The Wanderer <wanderer@fastmail.fm> - 2024-06-25 00:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file "Andrew M.A. Cater" <amacater@einval.com> - 2024-06-25 10:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file debian-user@howorth.org.uk - 2024-06-26 12:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file John Hasler <john@sugarbit.com> - 2024-06-26 18:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-26 19:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-28 06:20 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Erwan DAVID <erwan@rail.eu.org> - 2024-06-28 07:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file John Crawley <john@bunsenlabs.org> - 2024-06-28 08:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-28 11:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file John Crawley <john@bunsenlabs.org> - 2024-06-30 03:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file "Roy J. Tellason, Sr." <roy@rtellason.com> - 2024-06-25 20:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-25 21:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-26 03:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-26 02:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-26 02:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-23 14:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-24 02:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Curt <curty@free.fr> - 2024-06-23 17:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-26 02:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-21 13:20 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-22 17:00 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-22 18:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-23 06:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Jeffrey Walton <noloader@gmail.com> - 2024-06-23 07:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-21 06:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Max Nikulin <manikulin@gmail.com> - 2024-06-22 05:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-22 07:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-22 17:20 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-23 04:40 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-23 05:10 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file John Hasler <john@sugarbit.com> - 2024-06-23 21:50 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-26 02:30 +0200
                Re: System time/timezone, was Re: Maximum size .bash_aliases file Stefan Monnier <monnier@iro.umontreal.ca> - 2024-06-20 04:00 +0200
      time display was: Re: Maximum size .bash_aliases file debian-user@howorth.org.uk - 2024-06-17 17:00 +0200
        Re: time display was: Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-17 17:10 +0200
        Re: time display was: Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-22 10:20 +0200
          Re: time display was: Re: Maximum size .bash_aliases file Default User <hunguponcontent@gmail.com> - 2024-06-22 16:30 +0200
      Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-20 13:10 +0200
        Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-20 13:20 +0200
          Re: Maximum size .bash_aliases file The Wanderer <wanderer@fastmail.fm> - 2024-06-20 13:30 +0200
            Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-22 10:30 +0200
              Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-22 16:10 +0200
        Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-21 06:30 +0200
          Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-22 10:40 +0200
            Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-22 16:10 +0200
              Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-22 17:00 +0200
                Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-22 18:30 +0200
                Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-23 06:30 +0200
              Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-25 10:40 +0200
                Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-25 13:20 +0200
                Re: Maximum size .bash_aliases file debian-user@howorth.org.uk - 2024-06-25 14:30 +0200
                Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-25 15:00 +0200
                Australia/Eucla timezone abbreviation (was: Re: Maximum size  .bash_aliases file) Max Nikulin <manikulin@gmail.com> - 2024-06-25 17:20 +0200
            Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-22 17:10 +0200
              Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-25 10:50 +0200
  Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-17 06:40 +0200
    Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-17 10:50 +0200
      Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-17 11:20 +0200
        Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-17 14:10 +0200
          Re: Maximum size .bash_aliases file <tomas@tuxteam.de> - 2024-06-17 14:20 +0200
      Re: Maximum size .bash_aliases file Greg Wooledge <greg@wooledge.org> - 2024-06-17 13:30 +0200
      Re: Maximum size .bash_aliases file David Wright <deblis@lionunicorn.co.uk> - 2024-06-17 17:50 +0200
  Re: Maximum size .bash_aliases file Keith Bainbridge <keithrbau@gmail.com> - 2024-06-17 11:00 +0200

csiph-web