techgaun / unix-time

Unix time in various languages - A reference

unix-time

Unix time in various languages - A reference

What is Unix time?

Unix time (also known as POSIX time or erroneously as Epoch time) is a system for describing instants in time, defined as the number of seconds that have elapsed since 00:00:00 Coordinated Universal Time (UTC), Thursday, 1 January 1970, not counting leap seconds.

Examples

How to get current unix time

UTaaS (Unix Timestamp as a Service) (generic)

curl https://icanhazepoch.com/

C

#include <stdio.h>
#include <time.h>

int main(int argc, char **argv) {
  unsigned int unix_time = (unsigned) time(NULL);
  fprintf(stdout, "%u\n", unix_time);
  return 0;
}

C++

#include <iostream>
#include <ctime>

using namespace std;

int main(int argc, char **argv) {
  unsigned int unix_time = (unsigned) time(NULL);
  cout << unix_time << endl;
  return 0;
}

Elixir

# first way
DateTime.utc_now |> DateTime.to_unix

# second way
System.system_time(:second)

Erlang

os:system_time(second).

Golang

now := time.Now()
unixTs := now.Unix()

Java

long timestamp = System.currentTimeMillis()/1000;
System.out.println(timestamp);

Java 8 brings a new API to work with date and times, Instant. A good read about why JSR-310 is not same as joda-time. You can get current unix time on Java 8 by doing something like below:

long timestamp = Instant.now().getEpochSecond();
System.out.println(timestamp);

Javascript

Math.floor(new Date() / 1000)

Moment is very popular in javascript world for playing with dates in javascript. Below is the momentjs example.

var moment = require('moment');
var unixtime = moment().unix();

PHP

echo time();

//php5.3 and above
//OOP style
$date = new DateTime();
echo $date->getTimestamp();

//procedural style
$date = date_create();
echo date_timestamp_get($date);

Python

from time import time
print(int(time()))

import datetime
print(int(datetime.datetime.utcnow().timestamp()))

Ruby

Time.now.to_i