From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Rosenberg Subject: Re: Millisecond precision in timestamps? Date: Thu, 6 Dec 2012 00:37:01 +0100 (CET) Message-ID: <2439538.19317881.1354750621740.JavaMail.root@dewire.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: Junio C Hamano , Jeff King , Shawn Pearce , Felipe Contreras , git , esr@thyrsus.com To: David Aguilar X-From: git-owner@vger.kernel.org Thu Dec 06 00:45:12 2012 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1TgOeO-0002Oa-DK for gcvg-git-2@plane.gmane.org; Thu, 06 Dec 2012 00:45:12 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752842Ab2LEXo4 (ORCPT ); Wed, 5 Dec 2012 18:44:56 -0500 Received: from zimbra.dewire.com ([83.140.172.131]:38525 "EHLO zimbra.dewire.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752787Ab2LEXoz (ORCPT ); Wed, 5 Dec 2012 18:44:55 -0500 X-Greylist: delayed 472 seconds by postgrey-1.27 at vger.kernel.org; Wed, 05 Dec 2012 18:44:55 EST Received: from localhost (localhost [127.0.0.1]) by zimbra.dewire.com (Postfix) with ESMTP id 9510B825B1; Thu, 6 Dec 2012 00:37:02 +0100 (CET) X-Virus-Scanned: amavisd-new at dewire.se Received: from zimbra.dewire.com ([127.0.0.1]) by localhost (zimbra.dewire.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id tWSZ+yuUPpmH; Thu, 6 Dec 2012 00:37:01 +0100 (CET) Received: from zimbra.dewire.com (zimbra.dewire.com [10.1.2.96]) by zimbra.dewire.com (Postfix) with ESMTP id C3B8C824FA; Thu, 6 Dec 2012 00:37:01 +0100 (CET) In-Reply-To: X-Originating-IP: [213.67.12.15] X-Mailer: Zimbra 7.2.0_GA_2681 (ZimbraWebClient - FF3.0 (Mac)/7.2.0_GA_2681) Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: ----- Ursprungligt meddelande ----- > On Tue, Nov 27, 2012 at 11:58 PM, Eric S. Raymond > wrote: > > Junio C Hamano : > >> Roundtrip conversions may benefit from sub-second timestamps, but > >> personally I think negative timestamps are more interesting and of > >> practical use. > > > > You mean, as in times before the Unix epoch 1970-01-01T00:00:00Z? > > > > Interesting. I hadn't thought of that. I've never seen a software > > project under version control with bits that old, which is > > significant > > because I've probably done more digging into ancient software than > > anybody other than a specialist historian or two. > > One example I've heard is someone wanting to throw the history > of a country's laws into git so they can diff them. Not sure any laws were passed on Feb 30th 1712 in sweden, but perhaps you can define new time zones to handle that, but I doubt it is practically doable when you get to countries and regions with less precise boundaries. Seconds-since as a representation for dates is a dangerous and very messy game. Java gets it wrong somewhere in 1910 and my guess is others get it wrong too. There is change in time zones which triggers the bug. -- robin