From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp11.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 CNCnNOwS1mOiBwEAbAwnHQ (envelope-from ) for ; Sun, 29 Jan 2023 07:32:12 +0100 Received: from aspmx1.migadu.com ([2001:41d0:2:bcc0::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp11.migadu.com with LMTPS id aE+lNOwS1mOPPQEA9RJhRA (envelope-from ) for ; Sun, 29 Jan 2023 07:32:12 +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 AD6BE15507 for ; Sun, 29 Jan 2023 07:32:12 +0100 (CET) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pM1E2-0001WZ-RF; Sun, 29 Jan 2023 01:31:38 -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 1pM1E1-0001VS-J6 for emacs-orgmode@gnu.org; Sun, 29 Jan 2023 01:31:37 -0500 Received: from ciao.gmane.io ([116.202.254.214]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pM1E0-00071H-6P for emacs-orgmode@gnu.org; Sun, 29 Jan 2023 01:31:37 -0500 Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1pM1Dv-0009zO-3V for emacs-orgmode@gnu.org; Sun, 29 Jan 2023 07:31:31 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: emacs-orgmode@gnu.org From: Max Nikulin Subject: Re: [FEATURE REQUEST] Timezone support in org-mode datestamps and org-agenda Date: Sun, 29 Jan 2023 13:31:25 +0700 Message-ID: References: <63c9b654.170a0220.d82d2.4254@mx.google.com> <87mt6e86sr.fsf@tsdye.online> <63c9d976.620a0220.a7d40.113b@mx.google.com> <87tu0mjb24.fsf@tsdye.online> <63ca1283.170a0220.5bc81.0fdd@mx.google.com> <87pmb9k8oi.fsf@tsdye.online> <3035CDD5-41DD-4516-9E4E-9E0DF16BE2E0@gmail.com> <63d43ec5.630a0220.87fac.44e2@mx.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.2 Content-Language: en-US In-Reply-To: Received-SPF: pass client-ip=116.202.254.214; envelope-from=geo-emacs-orgmode@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: 16 X-Spam_score: 1.6 X-Spam_bar: + X-Spam_report: (1.6 / 5.0 requ) BAYES_00=-1.9, DKIM_ADSP_CUSTOM_MED=0.001, FORGED_GMAIL_RCVD=1, FORGED_MUA_MOZILLA=2.309, FREEMAIL_FORGED_FROMDOMAIN=0.15, FREEMAIL_FROM=0.001, HEADER_FROM_DIFFERENT_DOMAINS=0.249, NICE_REPLY_A=-1.148, NML_ADSP_CUSTOM_MED=0.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no 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-Flow: FLOW_IN X-Migadu-Country: US ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1674973932; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=lT6qp14Eli9lJZvuODxhLQGBqVc++HYF9RSK/AtpYFk=; b=WfKjpq+DqQrA95MtOi8REuNHM2uZwQlYIwMSh1JiinL4L+t/WkCGf+KZeIf6b3z3PDu34K O9Rl42fq9hiQg4ZLKNqdaj+GoV2USFM7nTbXpZqvNqkJDUeIYWGMK9ju3LquP2ibFFTNG9 PyB6vwYDj8JxvhVpyjCsfnA0/h9B6nQwQHHavXmOQ37ejsQ0+/gl821ekuT9a/nv10jF5r lRRzuCi9EZjjfBfu+RsIILzepbnFHsByV57pU3zRQcvcKox8BS9wSotMK7pEfBZLsd/hsn TvnFh8bK8kaUTjNe0NKrWgmrNum++52Bzlvdry1z243zZ0nphmsaSXIjp/uJlQ== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=none; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=gmail.com (policy=none); 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" ARC-Seal: i=1; s=key1; d=yhetil.org; t=1674973932; a=rsa-sha256; cv=none; b=nBgMZeusLoz5eir+FfXGYl0IjT0Ua/cAb7YgAquxNpGqkWRsDdcuO8PZJzMiH7sjaejrG9 0gq/54ChWxY5E9qc/2rH647k9LN4nMtBgFmSRD1DMH67JN2JrBGeZ5jrZspnl4cO0ibwGp EXFtKAuHaCXotLGPkxKzYVls0Coy3CvVkGr+WUXRK9LpX6iYc50uBHbl8jBlcHO/BUr2Pf NEenRfHHu/y/wob4Ze2YoIK5h/wG26aQ9ZTC+dRhDaU399hE5nKP6LXuyRs7xI10z4cHnm ndsgooHbUTQPiupRNsRWb2o1CJ1PjQwZ7X6Wg6QzvzwX/llbIZXj0c9KKfWMNw== Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=gmail.com (policy=none); 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" X-Migadu-Scanner: scn0.migadu.com X-Migadu-Spam-Score: -3.07 X-Spam-Score: -3.07 X-Migadu-Queue-Id: AD6BE15507 X-TUID: tBgckVkzqq5E On 29/01/2023 11:09, Jean Louis wrote: > * Tim Cross [2023-01-28 00:15]: >>>> • Offset (fixed) >>>> • This captures the idea of "when did it happen for the person who ------------------------------------^^^^^^^^^^^^^^^^^^^ Jean, you missed it. >>>> made the observation" >>>> • e.g., 2007-02-03T04:00:00.000+01:00 >>> >>> Offset is not that fixed, maybe from viewpoint of storage as maybe it ... >> I think your misinterpreting the intent here. If you specify a timestamp >> with offset, it is fixed. > > That is what you say. And I am pointing out to international standard > references. You reference and verbose message are hardly relevant. Since something has already happened, time offset is known. DST can not change it, either it is effective or not at this moment. 2007-02-03T04:00:00.000+01:00 can not be unambiguously attributed to an IANA timezone ID, however it precisely specifies UTC time (time in seconds since epoch, etc.). Usually (but not necessary) it means 04:00 local time in a timezone 1 hour ahead of UTC that moment (you may use it to specify 05:00 in timezone having +02:00 offset). It is enough for a lot of applications. There are important enough reasons to consider (and maybe discard to still use offset) IANA timezone ID for scheduling an event in future. Both options should be possible.