From owner-FreeBSD-users-jp@jp.freebsd.org  Thu Jan  7 20:53:50 1999
Received: (from daemon@localhost)
	by jaz.jp.freebsd.org (8.9.1+3.1W/8.7.3) id UAA05240;
	Thu, 7 Jan 1999 20:53:50 +0900 (JST)
	(envelope-from owner-FreeBSD-users-jp@jp.FreeBSD.org)
Received: from hokuto7.or.jp (mail.hokuto7.or.jp [210.156.98.2])
	by jaz.jp.freebsd.org (8.9.1+3.1W/8.7.3) with ESMTP id UAA05233
	for <FreeBSD-users-jp@jp.freebsd.org>; Thu, 7 Jan 1999 20:53:45 +0900 (JST)
	(envelope-from earth@hokuto7.or.jp)
Received: from localhost (192.168.2.202) by hokuto7.or.jp
 with SMTP (Eudora Internet Mail Server 1.3.1); Thu, 7 Jan 1999 21:02:09 +0900
To: FreeBSD-users-jp@jp.freebsd.org, ksr@lp.nm.fujitsu.co.jp
In-Reply-To: <wfr3e5nbmv6.fsf@kumando.lp.nm.fujitsu.co.jp>
References: <wfr67ajbns9.fsf@kumando.lp.nm.fujitsu.co.jp>
	<199901070629.PAA05405@aerith.cks.canon.co.jp>
	<wfr3e5nbmv6.fsf@kumando.lp.nm.fujitsu.co.jp>
	<199901050958.BAA24749@freefall.freebsd.org>
X-Mailer: Mew version 1.94b2 on XEmacs 20.4 (Emerald)
Mime-Version: 1.0
Content-Type: Text/Plain; charset=iso-2022-jp
Content-Transfer-Encoding: 7bit
Message-Id: <19990107205307O.earth@hokuto7.or.jp>
Date: Thu, 07 Jan 1999 20:53:07 +0900 (JST)
From: Hisashi Wakai <earth@hokuto7.or.jp>
X-Dispatcher: imput version 981124(IM104)
Lines: 103
Reply-To: FreeBSD-users-jp@jp.freebsd.org
Precedence: list
X-Distribute: distribute version 2.1 (Alpha) patchlevel 24e+981115
X-Sequence: FreeBSD-users-jp 37163
Subject: [FreeBSD-users-jp 37163] Re: y2k problem
Errors-To: owner-FreeBSD-users-jp@jp.freebsd.org
Sender: owner-FreeBSD-users-jp@jp.freebsd.org
X-Originator: earth@hokuto7.or.jp

From: TANAKA Keishiro <ksr@lp.nm.fujitsu.co.jp>
Subject: [FreeBSD-users-jp 37135] Re: y2k problem
Date: 07 Jan 1999 15:47:25 +0900
Message-ID: <wfr3e5nbmv6.fsf@kumando.lp.nm.fujitsu.co.jp>

ksr> $B$?(B>$B$3$N(B1904/1/1$B$H$$$&$N$O$I$3$+$iMh$F$k$s$G$7$g$&!#!#(B($B;EMM$NM3Mh(B)
ksr> >$B%^%C%-%s%H%C%7%e$N(B Excel $B$,!"(B1904 $BG/$r4p=`$K$7$F$$$k$&$h$&$G$9!#(B
ksr> Macintosh$B$N;~4V%+%&%s%?$O(Bunsigned 4 bytes$B$J$s$G$7$g$&$+!)(B
ksr> 1904$BG/(B + 136$BG/$G!"(B2040$BG/$4$m%*!<%P!<%U%m!<$H$$$&7W;;$G$$$$$s$G$7$g$&(B
ksr> $B$+!#!#(B

http://developer.apple.com/techpubs/mac/OSUtilities/OSUtilities-94.html#HEADING94-0
$B$K$h$l$P(B($B2~9T$OFI$_$d$9$$$h$&$KJQ$($F$"$j$^$9(B)$B!"(B

Date and Time

  A Macintosh computer contains a battery-operated clock chip 
  that maintains the current date-time information. 

  This date-time information is expressed, using 4 bytes,
  as the number of seconds elapsed since midnight, January 1, 1904. 

  At system startup the date-time information is copied into 
  low memory and is accessible through the system global variable Time. 

$B$G!"Cm0U=q$-$H$7$FD9$$4|4V$r07$&%=%U%H$O(BLongDateRec$B$r;H$&$h$&$K!"$H$"$j$^$9!#(B

Because the values in a date-time record are simply a translation of the long integer
containing the number of seconds since midnight, January 1, 1904, 
the data structure suffers the same limitation as the long integer representation: 
after the long integer has reached its maximum value of $FFFFFFFF, it resets to 0. 

Therefore, the date-time record can track dates and times only between midnight on
January 1, 1904 and 6:28:15 A.M. on February 6, 2040.

For some applications, this range might be inadequate. 
For example, a hotel management application might need to let managers book reservations 
for customers who think ahead to 2050, or a history multimedia application might need 
to track dates in the first century B.C. 

If your application needs to track dates and times beyond the range supported 
by the date-time record, you must use a long date-time record. 
A long date-time record is defined by a data structure of type LongDateRec

$B$3$l$@$H!"(B30,081 B.C. to 29,940 A.D. $B$r%+%P!<$G$-$k!"$H$"$j$^$9!#(B

http://www.apple.com/about/year2000/$B$K$O!"$h$j>\$7$$@bL@$,$"$j$^$9!#(B

$B8D!9$N%"%W%j%1!<%7%g%s(B $B%l%Y%k$G$O!"(B
$B5$$K$J$C$?$N$G!"F|:"!";H$C$F$$$k%U%!%$%k%a!<%+!<$rD4$Y$F$_$k$H!"(B
(http://claris2.claris.com/www-filemaker-com/about/year2000.html)

FileMaker Pro$B$N(B2.1$B0JA0$N%P!<%8%g%s$O!"(B
2$B7e$GG/9f$rF~NO$9$k$H!"(B1900$B$,B-$5$l$k$@$1$G$9!#(B
02.07.01$B$HF~NO$9$k$H!"(B4$B7eI=<($N%U%)!<%^%C%H$G$O!"(B1902.07.01$B$HI=<($5$l$^$9!#(B
$B:#;H$C$F$k%P!<%8%g%s$,$^$5$K$3$l$J$s$G!"(B
$B@>NqG/9f$NF~NO$O$9$Y$F(B4$B7e$K0\9T$9$k$3$H$K$7$J$/$F$O!#(B

$B$3$l0J9_$N%P!<%8%g%s$G$NBP:v$O!"(B

If the current year is among the LAST ten years of the century
(as in 1990-1999 or 2090-2099), then any two-digit year in the range
00-09 will be treated as a year in the FOLLOWING century.
(For example, if it's 1998, then 03 will be expanded to 2003 but 83 will be considered 1983.)

If the current year is among the FIRST ten years of the century (as in 2000-2009),
then any two-digit year in the range 90-99 will be treated as a year in the
PREVIOUS century. (For example, if it's 2002, then 97 will be treated as 1997 but
 83 will be considered 2083.)

http://www.apple.com/about/year2000/y2krhapsody.html
$B$K$O!"(B

Mach/BSD Implications

BSD keeps time as a signed 32-bit value that represents seconds since 1 Jan 00:00:00 GMT 1970. 
This format can represent times until Jan 19 03:14:07 GMT 2038.

$B$J$I$H!"(Brhapsody$B$G$NBP:v$J$I$,=q$+$l$F$^$9!#(B

$B@hF|!"FI$s$G$$$?(BUNIX MAGAZINE$B$K$b!"(By2k$B$N5-;v$,$"$j$^$7$?$,!"(B
$B$3$l$b(BY2K$BBP:v$J$s$G$9$M!#(B

danny> Subject: cvs commit: src/usr.bin/touch touch.c
danny> From: "Daniel O'Callaghan" <danny@FreeBSD.ORG>
danny> To: cvs-committers@FreeBSD.ORG, cvs-all@FreeBSD.ORG
danny> Date: Tue, 5 Jan 1999 01:58:02 -0800 (PST)
danny> 
danny> danny       1999/01/05 01:58:02 PST
danny> 
danny>   Modified files:
danny>     usr.bin/touch        touch.c 
danny>   Log:
danny>   PR:		9323
danny>   Submitted by:	ishisone@sra.co.jp
danny>   Make touch handle years 2000-2038 in the obsoleted format, rather
danny>   than 1902-1969 as was previously the case with two digit year spec.
danny>   
danny>   Revision  Changes    Path
danny>   1.7       +4 -1      src/usr.bin/touch/touch.c

 --
earth
