Date format POSIX (Unix timestamp, Linux)
Unix time, POSIX time Unix time, POSIX time – is a time representation system that measures the number of seconds that passed since 1970 (the beginning of the Unix era - 1 January 1970 00:00:00 GMT Epoch).
The actual number of seconds elapsed since the beginning of the Unix age (Epoch) is higher by & nbsp; the number of leap seconds from due to the difference between the time measured by the time patterns (the minimum slower time) and the natural solar time.
The leap seconds are therefore added to systems that distribute accurate time signals (e.g., DCF77, NTP) to synchronize the universal time coordinated with the average solar time.
In the Unix and operating systems, the time is shown as a 32-bit number of seconds that have passed since the early 1970s. The time interval is therefore limited by a value of 2 147 483 647.
First billion seconds "Unix billennium" from the beginning of the Unix era passed September 9, 2001, at 01:46:40 GMT. Unix systems were resistant to the so-called the problem of the year 2000. However, the 32-bit Unix time will run out on January 19, 2038 at & nbsp; 03:14:07 UTC - what can be called the problem of the year 2038.
POSIX, epoch, Linux Time Stamp, ISO 8601, UNIX Time Stamp, online convert, unix billennium: 1 000 000 000, 2001-09-09 01:46:40 (GMT)
Date format ISO 8601
In the ISO 8601 standard, dates can be presented in three different ways: calendar dates, cleaning dates and weekly dates. The standard is based on the Gregorian calendar.
The Polish equivalent is the standard PN-EN 28601: 2002
Calendar date
The year is recorded using four digits. The starting date year 0001 means 1 year A.D., Year 0000 means 1 year B. C. A year -0001 means 2 years. B. C.
The day is counted consecutively each month and the date is saved in the format YYYY-MM-DD where YYYY is the year, MM is the sequence number of the month and DD is the sequence number of the day.
Time during the day is saved with & nbsp; seconds accuracy in & nbsp; form HH: MM: SS.
The full calendar date saved in the ISO 8601 format has the form: YYYY-MM-DD HH:MM:SS.
Date of ordinal
On the ordinal date there is no division into months, and each day is recorded as the next yearly YYYY-DDD (2005-002 means 2 January day of 2005, and 2012-366 means December 31, 2012, where 2012 is a leap year)
Weekly date
Date saved in a weekly format has the form 2015W053 which means the fifth week, the 3rd day of the week, Wednesday (W).
