From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp10.migadu.com ([2001:41d0:2:bcc0::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms5.migadu.com with LMTPS id 4LTuIXa+wmMxBQAAbAwnHQ (envelope-from ) for ; Sat, 14 Jan 2023 15:38:46 +0100 Received: from aspmx1.migadu.com ([2001:41d0:2:bcc0::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp10.migadu.com with LMTPS id WCe1IHa+wmMKCAEAG6o9tA (envelope-from ) for ; Sat, 14 Jan 2023 15:38:46 +0100 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by aspmx1.migadu.com (Postfix) with ESMTPS id A469533B2D for ; Sat, 14 Jan 2023 15:38:45 +0100 (CET) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pGhfS-0003ri-SU; Sat, 14 Jan 2023 09:37:58 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pGhfL-0003ni-9R for emacs-orgmode@gnu.org; Sat, 14 Jan 2023 09:37:54 -0500 Received: from mout01.posteo.de ([185.67.36.65]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pGhfI-0006UP-Vw for emacs-orgmode@gnu.org; Sat, 14 Jan 2023 09:37:51 -0500 Received: from submission (posteo.de [185.67.36.169]) by mout01.posteo.de (Postfix) with ESMTPS id 6C2EC240164 for ; Sat, 14 Jan 2023 15:37:46 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=posteo.net; s=2017; t=1673707066; bh=YnJEjZlx9bPgNvrKvj0jPjjipbWvBCITxIbv1rQZPeI=; h=From:To:Cc:Subject:Date:From; b=sMtv1fuFxhkkVMRYYR5nX7VhHiKMTNvTFuJcDU/3C7lp3qsn0Ww9XgdBcZHmPvUmU vVTIoCYDOVvD+sXsrDfi3mLwd/CsoQcCZM2UvQbzHoOyUo0PbEpDvOol/9Rz94oicT EdILA5jT4mmqEQPXk/zZcqQlqHBerxRe5tAYYiicpnu7TDmZUUsozTbECM/nk+F9zA ya663jm1yw3UgRYuxYjucvLfGvRukSwgQ2rgGYD6DH14NoE65segX7lqn5N4sIpnS1 6UqJzt8yQyroPOv1XQrRkzQYx3k8i9nlHz1JqhFRz9zyT1ILHt21+8rIIxg7VaYYhz 8E0SWMsCEKHew== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4NvLVJ4gngz9rxH; Sat, 14 Jan 2023 15:37:44 +0100 (CET) From: Ihor Radchenko To: Tim Cross Cc: Max Nikulin , emacs-orgmode@gnu.org Subject: Re: [FEATURE REQUEST] Timezone support in org-mode datestamps and org-agenda In-Reply-To: <63c2b8e4.a70a0220.e3b6d.0051@mx.google.com> References: <63c287ca.a70a0220.4bd14.873b@mx.google.com> <87pmbh1hgx.fsf@localhost> <63c2b8e4.a70a0220.e3b6d.0051@mx.google.com> Date: Sat, 14 Jan 2023 14:38:05 +0000 Message-ID: <87edrxyyeq.fsf@localhost> MIME-Version: 1.0 Content-Type: text/plain Received-SPF: pass client-ip=185.67.36.65; envelope-from=yantar92@posteo.net; helo=mout01.posteo.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-orgmode@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "General discussions about Org-mode." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-orgmode-bounces+larch=yhetil.org@gnu.org Sender: emacs-orgmode-bounces+larch=yhetil.org@gnu.org X-Migadu-Country: US X-Migadu-Flow: FLOW_IN ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=pass header.d=posteo.net header.s=2017 header.b=sMtv1fuF; spf=pass (aspmx1.migadu.com: domain of "emacs-orgmode-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="emacs-orgmode-bounces+larch=yhetil.org@gnu.org"; dmarc=pass (policy=none) header.from=posteo.net ARC-Seal: i=1; s=key1; d=yhetil.org; t=1673707126; a=rsa-sha256; cv=none; b=RENyb9d6+MXeyBAyKowDYujNFVuPM89AJRchndXtHzoNNHoxjsts92Bqsr5fCwGoVuvykE sExGXxfxZx6hcr2LxglYLH0fucTY0SZ055g66NACH1ATpL2nkbsupk6W/1M8Xw8UfKIAVU 0T7894866KWGvnK6e0ej487zmb/a2iG1CRdavTiKs7hx4bydlnaYhgVyrcaVs/GLfgFawv 9N1hBYoh+c5xVSh8Vnjs4AXFvxKF7WQ726Cmydy+9WkCXMmsu+PjO3+VkL3n8bdgLd2UGc JoKRJm3K0x/9pqvT9yqxxV2NllfbMFUyIkAA3v5BRHat++QXR8pDSnqkmcmv0g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1673707126; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references:list-id:list-help:list-unsubscribe: list-subscribe:list-post:dkim-signature; bh=Eq3VAMV4B7vqRNa5dicfPhXMw24hzgcGOolt/RfFNzI=; b=B4S961Y0BKwsRTixczllvgp2yvJAgjSkfT8D0FeUFZ3t+k7/m/82pvJ5bwu+JiLGSBgIIy fVsVq/5tZ6/tcS7nT0axecD4UbTY5PJu03KHDg1+hqD0q8GDqFALWuxV6zLw89/qlmF1ew odkyiR3yyU2S419MhG8l8qYs1+RcrH6T/PPxKa/AxgBF7CT7dQu73zSMtR2LWzLiwhVmd9 hDADEi8jY6r9ZHWsQa9Ve/9VmbDPCbKPB2WCs63u4JiTHL+E2brupSAlTzeABmkN2m5SOv 07YeOpIYrD5Ry1moGzfoZLvcxyYyy/gpyWtMthITjwZifQD4vLMfsfHHB9hNDQ== X-Migadu-Queue-Id: A469533B2D X-Migadu-Scanner: scn0.migadu.com Authentication-Results: aspmx1.migadu.com; dkim=pass header.d=posteo.net header.s=2017 header.b=sMtv1fuF; spf=pass (aspmx1.migadu.com: domain of "emacs-orgmode-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="emacs-orgmode-bounces+larch=yhetil.org@gnu.org"; dmarc=pass (policy=none) header.from=posteo.net X-Migadu-Spam-Score: -10.86 X-Spam-Score: -10.86 X-TUID: sS7Q2IQv0Ntk Tim Cross writes: >> This is not the problem we need to worry about. We can use whatever >> Emacs provides and rely on future improvements in Emacs where things are >> deficient. We should not aim for 100% accurate time zone support. Just >> good enough. It's not Org's job to implement the gory details of time >> zone support. > > I guess we will have to disagree here. If org is going to claim to > support time zones, then 100% accurate is IMO essential. As it stands > now, we don't claim TZ support and time calculations are correct on the > basis they are all done relative to current locale. However, once you > add TZ information, if you don't apply it consistently and correctly, > that means the values can no longer be relied upon. > > Or to put it in another way - currently, it is well understood where org > timestamps fall down. However, once you add TZ and provide the > expectation TZ data will be respected correctly, all bets are off. I think I need to clarify. Emacs currently relies on glibc time zone support on Linux. I am not sure if glibc is 100% accurate, but it should be good enough. At least, there is no way we can do better ourselves. -- Ihor Radchenko // yantar92, Org mode contributor, Learn more about Org mode at . Support Org development at , or support my work at