From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell Adams Subject: Re: Timezones revisited Date: Wed, 1 Feb 2017 17:20:16 +0100 Message-ID: <20170201162016.GJ7187@volibear.adamsinfoserv.com> References: <20170131230346.GV7187@volibear.adamsinfoserv.com> <87shnxuczj.fsf@pellet> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:57042) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cYxeU-00071o-Se for emacs-orgmode@gnu.org; Wed, 01 Feb 2017 11:21:00 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cYxeP-0002A1-Ov for emacs-orgmode@gnu.org; Wed, 01 Feb 2017 11:20:58 -0500 Received: from bongo.ash.relay.mailchannels.net ([23.83.222.21]:42434) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cYxeP-00029d-2t for emacs-orgmode@gnu.org; Wed, 01 Feb 2017 11:20:53 -0500 Received: from relay.mailchannels.net (localhost [127.0.0.1]) by relay.mailchannels.net (Postfix) with ESMTP id 2035021AF1 for ; Wed, 1 Feb 2017 16:20:48 +0000 (UTC) Received: from kefka.asoshared.com (unknown [100.96.16.128]) by relay.mailchannels.net (Postfix) with ESMTPA id 2FCAC20951 for ; Wed, 1 Feb 2017 16:20:47 +0000 (UTC) Received: from 5ed25635.cm-7-3b.dynamic.ziggo.nl ([94.210.86.53]:62831 helo=localhost) by kefka.asoshared.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.87) (envelope-from ) id 1cYxeI-0000On-3Q for emacs-orgmode@gnu.org; Wed, 01 Feb 2017 11:20:46 -0500 Content-Disposition: inline In-Reply-To: List-Id: "General discussions about Org-mode." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org Sender: "Emacs-orgmode" To: emacs-orgmode@gnu.org On Wed, Feb 01, 2017 at 11:14:15AM -0500, Peter Neilson wrote: > On Wed, 01 Feb 2017 10:50:24 -0500, Eric Abrahamsen > Presumably everyone already knows that the timezones are more complicat= ed > than hoi polloi believe? The offsets are not always integer values of > hours. For example, Newfoundland time is UTC=E2=88=9203:30. Additional > complications include daylight saving time and the many historical > versions of timezones. The definition of UTC can remain pretty much > constant, but local-timezone time varies as a function of both location > and calendar date. Emacs has a timezone conversion function, which I assume pulls from the tz info database like all the other system commands. Local time zone should be the system time zone or one defined as a per-buffer variable. > Allowing user-defined functions (as simple or as complicated as one > desires) for translation from UTC might be best. I don't think we have to build anything from scratch. I think we just need to take an extra TZ parameter in the input dialog and then run it through the Emacs tz conversion function to get local time as the final time we store. ------------------------------------------------------------------ Russell Adams RLAdams@AdamsInfoServ.com PGP Key ID: 0x1160DCB3 http://www.adamsinfoserv.com/ Fingerprint: 1723 D8CA 4280 1EC9 557F 66E8 1154 E018 1160 DCB3