Can unix timestamps change in time?

Question

As the subject asks; change UNIX timestamps in each time zone?

For example, if I sent a request to another letter on the other side of the world, which says: "Send an email when the time is 1397484936" , will there be another server timestamp 12 hours lower than mine?

Answer 1

The UNIX timestamp definition depends on the time zone. A timestamp is the number of seconds (or milliseconds) elapsed since the absolute moment in time, midnight January 1, 1970 in UTC. (UTC - Greenwich Mean Time without daylight saving time adjustment). Regardless of your time zone, a timestamp is a moment that is the same everywhere. Of course, you can convert back and forth to the local time zone representation (time 1397484936 is such and such local time in New York or some other local time in Jakarta) if you want.

The article at http://en.wikipedia.org/wiki/Unix_time is quite impressive if you want a longer read.

Answer 2

Unix time is defined as the number of seconds elapsed since 00:00:00. Coordinated Universal Time ( UTC ), Thursday January 1, 1970. So the answer is no

Answer 3

IF both computers are configured correctly with the clock set for the correct time zone and UTC values, they should return the same value.
Of course, this is a big IF. There will almost certainly be a difference of at least a second, more often minutes, between the time reported by two computers. And many computers are set to the wrong time zone settings and report their local time when they set the time stamp, not UTC.

And that is the difference between theory and practice. Theoretically, this is the same; in practice, you should never rely on it.

Answer 4

Unix timestamps do not change by time zone ; they are created for the purpose of standard time around the world.

Note: - Timestamps are calculated based on the current time on the computer, so do not rely on them until you are confident in the time settings on the participating machines.

Answer 5

Someone stated that "UTC is Greenwich Mean Time excluding daylight saving time." This is simply not true. There is no daylight saving time in GMT. GMT is measured at Greenwich, England (at the Naval Observatory) [0 longitude, but not 0 latitude]. UTC is measured at the equator [0 longitudes and 0 latitudes - which lie in the ocean outside of Africa).

What does it change? It doesn’t matter in terms of “what time of day is it?” This, however, is significant in terms of calculating the year. Now you think that the year will be measured depending on the location of the center (core) of the Earth, right? When the Earth’s core returned to the same place where it was ~ 365 days ago, it was a year. It is not measured in this way. It is measured by a specific location on Earth returning to the same place (relative to the Sun), which was ~ 365 days ago. But the period of the day and year is not divided equally. As soon as the Earth returns to where it was a year ago, the Earth will no longer look in the same direction as last year, so the point on the earth will not look in the same direction as a year ago. Farther north, Greenwich is not going to return to the same place (relative to the Sun) that it was last year at the same time as 0 Lat / 0 Long. Therefore, if you base your definition on Greenwit against 0/0, you will get, albeit slightly, a different answer to the question “how many days in a year”. In other words, when a given place on earth returns to where it was a year ago (relative to the Sun), the core of the Earth is not in the same place as a year ago, so what is this place? You choose things because the core of the Earth will be in a different place (relative to the Sun) than it was a year ago if you choose a different place on Earth.

Neither UTC nor GMT have daylight saving time. Europe / London time, the time zone in which Greenwich resides does. But GMT not. GMT is what Americans call "standard time," that is, without DST.

Returning to the question, the time of the era does not technically have a time zone. It is based on a specific moment in time, which, as it turned out, coincides with the “even” UTC time (at the beginning of the year, decade, etc.). If this concept does not fit into your brain, and if it helps to think of an era’s time as UTC, continue. You are in good company and by and large, it really does not matter. Have you ever seen those lawsuits where somoene is awarded $ 1. This is a kind of sentence like "you're right, but that doesn't matter." If someone sues you for saying that Epoch time is in the UTC time zone, he will win $ 1. It would not buy them a cup of coffee in any Starbucks in any time zone on the planet.