From owner-freebsd-stable@FreeBSD.ORG  Sun Oct 28 18:36:51 2007
Return-Path: <owner-freebsd-stable@FreeBSD.ORG>
Delivered-To: stable@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 4E7F616A419
	for <stable@freebsd.org>; Sun, 28 Oct 2007 18:36:51 +0000 (UTC)
	(envelope-from eugen@www.svzserv.kemerovo.su)
Received: from www.svzserv.kemerovo.su (www.svzserv.kemerovo.su
	[213.184.65.80])
	by mx1.freebsd.org (Postfix) with ESMTP id AB32813C4A5
	for <stable@freebsd.org>; Sun, 28 Oct 2007 18:36:50 +0000 (UTC)
	(envelope-from eugen@www.svzserv.kemerovo.su)
Received: from www.svzserv.kemerovo.su (eugen@localhost [127.0.0.1])
	by www.svzserv.kemerovo.su (8.13.8/8.13.8) with ESMTP id l9SIZ8ie025710;
	Mon, 29 Oct 2007 01:35:08 +0700 (KRAT)
	(envelope-from eugen@www.svzserv.kemerovo.su)
Received: (from eugen@localhost)
	by www.svzserv.kemerovo.su (8.13.8/8.13.8/Submit) id l9SIZ8A0025709;
	Mon, 29 Oct 2007 01:35:08 +0700 (KRAT) (envelope-from eugen)
Date: Mon, 29 Oct 2007 01:35:08 +0700
From: Eugene Grosbein <eugen@kuzbass.ru>
To: Holger Kipp <hk@alogis.com>
Message-ID: <20071028183508.GA25172@svzserv.kemerovo.su>
References: <20071028174832.GA21847@svzserv.kemerovo.su>
	<20071028182011.GA89664@intserv.int1.b.intern>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20071028182011.GA89664@intserv.int1.b.intern>
User-Agent: Mutt/1.4.2.3i
Cc: stable@freebsd.org
Subject: Re: date manupulation strangeness
X-BeenThere: freebsd-stable@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Production branch of FreeBSD source code <freebsd-stable.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>, 
	<mailto:freebsd-stable-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-stable>
List-Post: <mailto:freebsd-stable@freebsd.org>
List-Help: <mailto:freebsd-stable-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>,
	<mailto:freebsd-stable-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 28 Oct 2007 18:36:51 -0000

On Sun, Oct 28, 2007 at 07:20:11PM +0100, Holger Kipp wrote:

> > # unixtime=1193511599
> > # LC_ALL=C TZ=Asia/Krasnoyarsk date -jr $unixtime
> > Sun Oct 28 02:59:59 KRAT 2007

Here it shows 'Sun Oct 28 02:59:59 KRAST 2007' really
(cut-n-paste error, mea culpa). Take a note of zone name,
KRAST stands for 'KRAsnoyarsk Summer Time' and
KRAT stands for 'KRAsnoyarsk Time' (winter one).

> > That's last second of Summer time in this time zone.
> > 
> > # LC_ALL=C TZ=Asia/Krasnoyarsk date -f %s $unixtime
> > Sun Oct 28 02:59:59 KRAT 2007
> > 
> > That's an hour later after the switch from Summer time,
> > but how can it be? It is a bug?
> 
> I haven't checked, but usually during switch from summer
> to winter time, you change the clock back from 03:00 to
> 02:00, so you have the same hour twice.
> 
> So you have 02:59:59 summer time and then you have
> (instead of 03:00:00) 02:00:00 winter time a second
> later, so one hour later you end up with 02:59:59 again.

Yes, but "02:59:59 KRAT" is one hour (minus one second) later
than "02:00:00 KRAT", the latter equals to "03:00:00 KRAST",
so the first invocation of 'date' command shows time an hour
before time the second invocation shows. However,
unixtime is the same. That bothers me, something is wrong.

Eugene