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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-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1675602142; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:cc: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:dkim-signature; bh=y77ODBgHEetxxtGo1EF1l1ajB30ZLUmbpyftBCMQV94=; b=UglFigtdXT9Fij7bF47LKtSSziGpS9AAyyFMVtB4TemdEZwPrGbf2X4M+qWgTr3b1JH3a+ JeDXfwSxVQ1I1GR7RfkWlOGwxHg6BvcNsgd6X/x95fsW3T4AXGBLBjP7vQaK+YVrLMtosD tvKGMF9c8JhQkmvof79YEkmKw3vYcL4/b8DN2OeuQeuts5wuUgwArG/hJ0XqP9/tfg64MY cHqsfFRhoi1DiDmiTruR/aldX1J8DZW/CVK12Uw6SxfwiQxVrr/sblugUQMMt269tmUPSH wiJCDmY7/4bZzNHKH5zr/6681lLtP0QGQCARaf+CiCVnQaOSOWfL1r/l9l0VVg== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=QFoI3GDX; 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=gmail.com ARC-Seal: i=1; s=key1; d=yhetil.org; t=1675602142; a=rsa-sha256; cv=none; b=eIb0AWgcAo/glwNOL0BQhCBQq786rP0xJuL7jAL4YaTGVbOdPJiJUy63p7Hz3K2v22oa0b +G0K+9NTAsQzz6uix6GJgSXC0B9Rwx2JH6pgEx3qISCS1lzQZf0JahijdEXI046ibbYOl6 tX1Hq39B5XuKmJ6aZ4639TERp1XzyPN5a8TSQO9pd6ihSGUejiZLuETz3EOl8Kjohn9BH8 MoIvQuoE8FwLPBxkoy5Yohh70UvFP7UHwA2kKGTdw+c7xHgjQG1ryCU2xJS/XFXax5L34s GD/qHpv4O46UQRIxTONMKVbF+Koabm1KMEAIIJcpBkdDUl5BSA/9WHyt1TdVQw== X-Migadu-Spam-Score: -4.28 X-Spam-Score: -4.28 X-Migadu-Queue-Id: B3D1C154EB Authentication-Results: aspmx1.migadu.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=QFoI3GDX; 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=gmail.com X-Migadu-Scanner: scn1.migadu.com X-TUID: by3BqcG2zD/e For the Poll, the Jeans proposal would be to introduce manually: [2024-02-04 12:00 @America/Vancouver] And org to convert it into: [2024-02-04 12:00 @-08,America/Vancouver] ? Ihor's would add the option to get warnings, in case tzdata changes, when t= hat timestamp is generated? [2024-02-04 12:00 @-08,!America/Vancouver] ? Feb 5, 2023 13:12:25 Jean Louis : > * Ihor Radchenko [2023-02-05 13:45]: >> [2024-02-04 12:00 @-08,America/Vancouver] will use fixed -8 offset >=20 > What does that mean practically? Provide example for better > understanding. >=20 > - The UTC offset is not certain to remain fixed in the future. >=20 > - If you do not have the time of creation of the timestamp above, you > =C2=A0 cannot know with certainty what was the offset in past, to calcula= te > =C2=A0 new UTC offset in case it changed >=20 > - As not even time zone is certain to remain in existence in future, > =C2=A0 you will need to use time zone, in order to derive that future UTC > =C2=A0 offset correctly. As it could change in mean time. >=20 > What is meaning of "fixed -8 offset"? >=20 >> [2024-02-04 12:00 @-08] will also use fixed -8 offset >=20 > That type of timestamp does not clearly show the time zone, that one > may only be understood as timestamp with UTC offset. UTC time may be > derived from such timestamp. That offset should remain fixed, as there > is no time zone associated. It is UTC time represented with offset. >=20 >> [2024-02-04 12:00 @America/Vancouver] will use @America/Vancouver time >> zone, as it is be defined in you OS time zone database. >=20 > If you do not keep UTC offset, you will miss changes in future and > generate errors. >=20 >> [2024-02-04 12:00 @-08,!America/Vancouver] (note "!") will use fixed -8 >> offset, but also calculate America/Vancouver time from TZ database, >> compare it with the time coming from -8 offset, and warn you if there is >> inconsistency. >=20 > The UTC offset is the log what was the UTC offset at the time point > when timestamp was created, as future UTC offset cannot be known. >=20 > Making it "fixed" does not fix it in real time, you are then > introducing something new than what other programs do with time. >=20 > I do not think that you need "!", you are creating work not necessary > for users. >=20 > If users wish to get some warnings, let them customize single option. >=20 > Not timestamp by timestamp. >=20 > -- > Jean >=20 > Take action in Free Software Foundation campaigns: > https://www.fsf.org/campaigns >=20 > In support of Richard M. Stallman > https://stallmansupport.org/