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   Jeff Martin (cuchaz@gladtech.social)'s status on Wednesday, 12-Feb-2025 12:35:08 JST Jeff Martin

   It's 2025 and somehow getting the correct local time in a multi-threaded #Rust / #RustLang program just isn't possible.

   Like ... seriously?

   Yes, there are workarounds. You can get non-local times, or (sometimes) incorrect local times.

   But the correct local time is always displayed on my screen 100% of the time already. Because clocks are a thing! And my code can't just ... get that somehow? This is pretty nuts.

   • Embed this notice
     varx/tech (varx@infosec.exchange)'s status on Wednesday, 12-Feb-2025 12:35:00 JST varx/tech

     in reply to

     @cuchaz Hmm... is that really true, though? If I'm in the Eastern time zone, the UTC offset changes twice a year, but I'm still in the time zone.

     (I don't know what EST and EDT are called, though, given that as far as I can tell, "ET" is the time zone.)

   • Embed this notice
     feld (feld@friedcheese.us)'s status on Wednesday, 12-Feb-2025 12:35:00 JST feld

     in reply to

     • varx/tech
     @varx @cuchaz EST Eastern Standard, EDT Eastern Daylight
   • Embed this notice
     Jeff Martin (cuchaz@gladtech.social)'s status on Wednesday, 12-Feb-2025 12:35:02 JST Jeff Martin

     in reply to

     • varx/tech

     @varx Right! But that only works if the timezone doesn't change on you while the program is running. Which happens (at least) twice a year in many places on Earth.

   • Embed this notice
     varx/tech (varx@infosec.exchange)'s status on Wednesday, 12-Feb-2025 12:35:03 JST varx/tech

     in reply to

     @cuchaz I see... *local* time means checking the env, and the env is a global mutable thing.

     So I guess you need to check the locale at startup, cache that somewhere, and use that explicitly whenever you need to get the time...

   • Embed this notice
     varx/tech (varx@infosec.exchange)'s status on Wednesday, 12-Feb-2025 12:35:04 JST varx/tech

     in reply to

     @cuchaz wait what

   • Embed this notice
     Jeff Martin (cuchaz@gladtech.social)'s status on Wednesday, 12-Feb-2025 12:35:04 JST Jeff Martin

     in reply to

     • varx/tech

     @varx Haha, yeah. It's nuts. Let me see if I can dig up that explainer again. There was a good reddit thread somewhere ...

     Ah, here it is:

     https://old.reddit.com/r/rust/comments/qs7l6p/psa_the_time_crate_once_again_supports_obtaining/hkcqesv/

   • Embed this notice
     feld (feld@friedcheese.us)'s status on Thursday, 13-Feb-2025 13:08:11 JST feld

     in reply to

     • varx/tech
     @varx @cuchaz I think I get what you mean
     
     I'd say ET describes a common geographic region that we believe generally experience daylight similarly enough but within are different countries / laws that further define the local rules.
     
     EST and EDT then are two universally understood timezone definitions applied to the eastern region in America during different parts of the year?
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     varx/tech (varx@infosec.exchange)'s status on Thursday, 13-Feb-2025 13:08:12 JST varx/tech

     in reply to

     • feld

     @feld @cuchaz Heh, sorry, what I mean is -- what is the *category* named? EST and EDT aren't "time zones", as far as I'm aware, because ET is the time zone. So what are they?