From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-3.1 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 Received: from second.openwall.net (second.openwall.net [193.110.157.125]) by inbox.vuxu.org (Postfix) with SMTP id E776622172 for ; Tue, 5 Mar 2024 23:31:48 +0100 (CET) Received: (qmail 7790 invoked by uid 550); 5 Mar 2024 22:27:53 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 7739 invoked from network); 5 Mar 2024 22:27:52 -0000 From: Russ Allbery To: Guy Harris Cc: Rich Felker , Ian Abbott via tz , musl@lists.openwall.com In-Reply-To: <77902F3C-198B-49BD-AB75-383A7FF45548@sonic.net> (Guy Harris's message of "Tue, 5 Mar 2024 14:12:29 -0800") Organization: The Eyrie References: <87edcqv69m.fsf@hope.eyrie.org> <20240305201247.GE4163@brightrain.aerifal.cx> <87wmqgpfcq.fsf@hope.eyrie.org> <87r0gopc9g.fsf@hope.eyrie.org> <77902F3C-198B-49BD-AB75-383A7FF45548@sonic.net> User-Agent: Gnus/5.13 (Gnus v5.13) Date: Tue, 05 Mar 2024 14:31:33 -0800 Message-ID: <87msrcpayi.fsf@hope.eyrie.org> MIME-Version: 1.0 Content-Type: text/plain Subject: [musl] Re: [tz] [musl] Re: Weird PST8PDT and EST5EDT behavior on Alpine Linux Guy Harris writes: > On Mar 5, 2024, at 2:03 PM, Russ Allbery wrote: >> It seems to support what I said: PST8PDT was supported, but :PST8PDT was not. > Yes. As I indicated, they didn't have tzdb code (if they did, that > would be a surprise, as the tzdb project didn't exist in 1979/1980), and > they didn't support any POSIX extensions to TZ (if they did, that would > be a surprise as, at least according to > https://en.wikipedia.org/wiki/POSIX, the first POSIX standard came out > in 1988). Ah, sorry, I had just misunderstood you. Thank you for the confirmation and reference! Basically, to summarize, up until now I think it was possible to set TZ to PST8PDT and have it work essentially everywhere, no matter how old the edition of UNIX, thanks to the backward compatibility file in tzdata. I think musl may have been the first place where this broke somewhat intentionally. This is not a big deal and I'm not sure I'm arguing that musl should change; I expect interfaces to change over time and it's probably time to assume everyone supports the Olson identifiers. But it is a change in the portability landscape, if a minor one. (Probably one that's been around for a while and I just never noticed because I hadn't been running the INN test suite on Alpine Linux.) -- Russ Allbery (eagle@eyrie.org)