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The Unix timestamp will begin with 16 this Sunday

unixtimestamp.com

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Re: The Unix timestamp will begin with 16 this Sunday

#131

Post by fanf2 »

bitpow wrote: post #113
sltkr wrote: post #89

Earlier quoted context omitted.

Yes, but the point is that the UNIX timestamp doesn't count the the number of seconds elapsed since January 1, 1970. It counts 86400 seconds per day, regardless of how many seconds the day actually has (which can vary due to leap seconds).

Is this accurate though? Isn’t the number of seconds since 1970 absolute, and it’s up to the library generating the Gregorian date to take into account leap seconds? I suppose if these libraries are not taking into account leap seconds, then the actual rollover will be a few seconds earlier (or later?) than what we think.

See the definition of seconds since the epoch at https://pubs.opengroup.org/onlinepubs/9699919799.2018edition...

  tm_sec + tm_min*60 + tm_hour*3600 + tm_yday*86400 +
      (tm_year-70)*31536000 + ((tm_year-69)/4)*86400 -
      ((tm_year-1)/100)*86400 + ((tm_year+299)/400)*86400

Re: The Unix timestamp will begin with 16 this Sunday

#132

Post by crooked-v »

lozf wrote: post #114
iso1210 wrote: post #59

I remember staying up late (UK) at the Billenium (2:46 AM Sunday Sep 9th 2001), thinking that was bound to be the most newsworthy event of the week, watching the seconds tick past on a "while(sleep 1); do date" loop, with slashdot in one window, IRC in another, all running on an enlightenment window manager. 500M seconds later I was in Washington DC in a hotel, watching it tick up on an rxvt on my laptop, with HN in…

> a "while(sleep 1); do date" loop, There's always "xclock -d -update 1 -strftime %s -face Inconsolata-190:bold "

You could at least give the event some proper gravitas by using Comic Sans instead.

Re: The Unix timestamp will begin with 16 this Sunday

#133

Post by quicklime »

iso1210 wrote: post #59

I remember staying up late (UK) at the Billenium (2:46 AM Sunday Sep 9th 2001), thinking that was bound to be the most newsworthy event of the week, watching the seconds tick past on a "while(sleep 1); do date" loop, with slashdot in one window, IRC in another, all running on an enlightenment window manager. 500M seconds later I was in Washington DC in a hotel, watching it tick up on an rxvt on my laptop, with HN in…

Hah nice, I remember doing that too! At the time I thought it was important to keep the irc log, which I've just dug up and thrown up on pastebin. I don't actually remember which network this was (EFNet maybe?)

> 03:46:49 -crier- THE BILLENNIUM HAS ARRIVED!!!!! Uh, you might want to play auldlangsyne.wav. YAAAAAAAAAAAAAAAYYYYYY!

more at https://pastebin.com/71H7eR8r

For some reason the billennium arrives at 3:46:49, which doesn't make sense - I wasn't in UTC+2, and anyway this should've been at 01:46:40am UTC (40 seconds past the minute, not 49 seconds). Most likely reason is simply that my local machine's clock was wrong.

Re: The Unix timestamp will begin with 16 this Sunday

#134

Post by delecti »

linkdd wrote: post #62
NGC404 wrote: post #40

Earlier quoted context omitted.

Next iteration of unix-time should include the concept of local time in context of relativty if we are going to travel or communicate over significant distances.

Einstein: There is no such thing as an absolute time Programmer: Hold my beer

More like:

Programmer: Next iteration of unix-time should include the concept of local time in context of relativity if we are going to travel or communicate over significant distances.

Einstein: Hold my beer

Re: The Unix timestamp will begin with 16 this Sunday

#136

Post by numpad0 »

flopunctro wrote: post #107
numpad0 wrote: post #94

Earlier quoted context omitted.

If relativity don’t allow time travel doesn’t it make time canonical? A clock on Earth from telescope might look jumpy but only in forward direction after compensating for distance I think

Looking at a clock from Earth through a telescope isn't as straightforward as you'd think. The image you see of that clock is actually light (photons) emitted from Earth, which will take a while to reach you - like, 1 year, if you're 1 lightyear away. During that year, Earth has moved on, maybe blew itself apart. But you can't even tell, because information can't reach you faster than light :) So you can only see Ear…

Yeah but can it ever go back, other than by backing off faster than the speed of light? If it can’t then it’s at least monotonic, even if it’s not rate constant

Re: The Unix timestamp will begin with 16 this Sunday

#140

Post by remram »

kazagistar wrote: post #80
komali2 wrote: post #58

Earlier quoted context omitted.

Yea, but if we're going to use a "number of seconds since ..." Type system like Unix time, SOMEONE has to be the origin point, so I don't think this is a knock against Unix time.

Its unfortunate to use an accelerating reference (earth rotating sun, sun rotating galaxy, galaxy intermixing with andromeda) because it requires you to awkwardly keep track of the astronomy of earth for timekeeping. Instead, you would want a standardized reference time frame, say, "unix time assuming earth in 1970 never experienced any acceleratiom or dilation" and then everyone, including earth people, would track…

You would want some global reference time, and that could be a number of seconds passing on Earth. However locally you can't work with a clock that doesn't tick at a constant rate (if seconds on your spaceship go twice as fast, the crew can work with that; if the rate changes day-to-day as you accelerate, that's a problem).

In addition, you will probably want clocks that run at a given perceived speed, to time physical processes that take the same time everywhere (e.g. so your cookie recipe saying "bake for 600 seconds" work without translation).

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