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To: "Cyrille Lefevre" <clefevre-lists@9online.fr>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 05 Feb 2004 12:43:02 +0100."
             <06ef01c3ebdd$36b53190$7890a8c0@dyndns.org> 
Date: Thu, 05 Feb 2004 12:56:31 +0100
Message-ID: <42697.1075982191@critter.freebsd.dk>
cc: "current @FreeBSD.org" <freebsd-current@freebsd.org>
Subject: Re: wrong kern.boottime 
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In message <06ef01c3ebdd$36b53190$7890a8c0@dyndns.org>, "Cyrille Lefevre" write
s:

>> ># last reboot
>> >reboot           ~                         Sun Feb  1 21:41
>> ># ls -l /var/run/dmesg.boot
>> ><
>> >-rw-r--r--  1 root  wheel  5547 Feb  1 21:40 /var/run/dmesg.boot
>> ># sysctl kern.boottime
>> >kern.boottime: { sec = 1075812223, usec = 350585 } Tue Feb  3 13:43:43 2004
>> ># uname -a
>> >FreeBSD gits 5.2-CURRENT FreeBSD 5.2-CURRENT #1: Sat Jan 31 15:17:05 CET 2004
>> >
>> >any idea ?
>>
>> What does "date" say on your machine ?
>
># date -u
>Thu Feb  5 11:39:36 UTC 2004
># date
>Thu Feb  5 12:39:39 CET 2004
># ls -l /etc/wall_cmos_clock
>-rw-r--r--  1 root  wheel  0 Jun  9  2001 /etc/wall_cmos_clock
>
>ntpd is running, so, I'm on time.

Hmm, I'm not sure where last gets it's number from, maybe from utmp.

If the utmp record is written on boot before ntpd corrects the clock
that would be one explanation...

Either way, I'm pretty sure that kern.boottime contains what it should
contain:  Our best estimate of the time when the system was booted.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.