From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.devel Subject: Re: [PATCH] Make display-time-mode time zone configurable Date: Tue, 16 Feb 2016 09:11:12 -0800 Organization: UCLA Computer Science Department Message-ID: <56C35830.4080107@cs.ucla.edu> References: <87fuwt8wek.fsf@udel.edu> <56C2A950.3080102@cs.ucla.edu> <87ziv0lo6i.fsf@example.com> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1455642718 31805 80.91.229.3 (16 Feb 2016 17:11:58 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 16 Feb 2016 17:11:58 +0000 (UTC) Cc: Mark Oteiza , emacs-devel@gnu.org To: "W. Greenhouse" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Feb 16 18:11:51 2016 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1aVjAF-0002LM-8E for ged-emacs-devel@m.gmane.org; Tue, 16 Feb 2016 18:11:51 +0100 Original-Received: from localhost ([::1]:48508 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aVjAE-00013W-Hm for ged-emacs-devel@m.gmane.org; Tue, 16 Feb 2016 12:11:50 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55790) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aVj9j-0000f0-KU for emacs-devel@gnu.org; Tue, 16 Feb 2016 12:11:20 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aVj9e-00006f-KP for emacs-devel@gnu.org; Tue, 16 Feb 2016 12:11:19 -0500 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:46866) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aVj9e-00005j-EO for emacs-devel@gnu.org; Tue, 16 Feb 2016 12:11:14 -0500 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 8775A160FD0; Tue, 16 Feb 2016 09:11:13 -0800 (PST) Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id XNLQITokwgG7; Tue, 16 Feb 2016 09:11:12 -0800 (PST) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id D333F160FD2; Tue, 16 Feb 2016 09:11:12 -0800 (PST) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id fAPLJkjZQR4D; Tue, 16 Feb 2016 09:11:12 -0800 (PST) Original-Received: from penguin.cs.ucla.edu (Penguin.CS.UCLA.EDU [131.179.64.200]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id B9FBD160FD0; Tue, 16 Feb 2016 09:11:12 -0800 (PST) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 In-Reply-To: <87ziv0lo6i.fsf@example.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 131.179.128.68 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:200043 Archived-At: On 02/16/2016 06:33 AM, W. Greenhouse wrote: > Also, as far as parts of Emacs that deal with time zones, there's also > `calendar-time-zone', which uses a totally different format (offset in > minutes, instead of zoneinfo-style names)! The calendar also seems to > NIH the handling of daylight saving time. Yes, the calendar code predates the new support for time zones at the lower level, and it suffers because of that. For example, if you had started Emacs in Cancun last year at 2015-02-01 01:59, its calendar would have been messed up, because Cancun changed its clocks a minute later (a time zone change, not a daylight-saving change) and Emacs would have cached the wrong standard time zone. Eventually we should fix this sort of bug by having the calendar code use the new lower-level primitives better.... > Now that I understand the role of `display-time-string-forms', I can > fix the problem for myself there without Mark's proposed defcustom, > but the defcustom raises visibility a lot for others who might have > the same desired wall-clock configuration as I. OK, how about if we wait for others to have problems that cannot be solved via display-time-string-forms and deal with the issues that come up then.