[epoch time] unix timestamp 쯤?

 

What is epoch time?

The Unix epoch (or Unix time or POSIX time or Unix timestamp) is the number of seconds that have elapsed since January 1, 1970 (midnight UTC/GMT), not counting leap seconds (in ISO 8601: 1970-01-01T00:00:00Z). Literally speaking the epoch is Unix time 0 (midnight 1/1/1970), but 'epoch' is often used as a synonym for 'Unix time'. Many Unix systems store epoch dates as a signed 32-bit integer, which might cause problems on January 19, 2038 (known as the Year 2038 problem or Y2038).  

Human readable time	Seconds
1 hour	3600 seconds
1 day	86400 seconds
1 week	604800 seconds
1 month (30.44 days)	2629743 seconds
1 year (365.24 days)	31556926 seconds

 

 

How to get the current epoch time in ...

PHP	time()
Python	import time first, then time.time()
Ruby	Time.now (or Time.new). To display the epoch: Time.now.to_i
Perl	time
Java	long epoch = System.currentTimeMillis()/1000;
C#	var epoch = (DateTime.UtcNow - new DateTime(1970, 1, 1)).TotalSeconds;
Objective-C	[[NSDate date] timeIntervalSince1970]; (returns double) or NSString *currentTimestamp = [NSString stringWithFormat:@"%f", [[NSDate date] timeIntervalSince1970]];
C++11	double now = std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()).count();
VBScript/ASP	DateDiff("s", "01/01/1970 00:00:00", Now())
AutoIT	_DateDiff('s', "1970/01/01 00:00:00", _NowCalc())
Delphi	Epoch := DateTimetoUnix(Now); Tested in Delphi 2010.
R	as.numeric(Sys.time())
Erlang	calendar:datetime_to_gregorian_seconds(calendar:universal_time())-719528*24*3600.
MySQL	SELECT unix_timestamp(now())
PostgreSQL	SELECT extract(epoch FROM now());
SQLite	SELECT strftime('%s', 'now');
Oracle PL/SQL	SELECT (SYSDATE - TO_DATE('01/01/1970 00:00:00', 'MM-DD-YYYY HH24:MI:SS')) * 24 * 60 * 60 FROM DUAL
SQL Server	SELECT DATEDIFF(s, '1970-01-01 00:00:00', GETUTCDATE())
JavaScript	Math.round(new Date().getTime()/1000.0) getTime() returns time in milliseconds.
Visual FoxPro	DATETIME() - {^1970/01/01 00:00:00} Warning: time zones not handled correctly
Adobe ColdFusion	<cfset epochTime = left(getTickcount(), 10)>
Tcl/Tk	clock seconds
Unix/Linux Shell	date +%s
PowerShell	get-date (get-date).touniversaltime() -uformat "%s"
Other OS's	Command line: perl -e "print time" (If Perl is installed on your system)

 

Convert from human readable date to epoch

PHP	strtotime("15 November 2012") (converts most English date texts) or: date_create('01/15/2010')->format('U') (PHP5 DateTime class)
Python	import time first, then int(time.mktime(time.strptime('2000-01-01 12:34:00', '%Y-%m-%d %H:%M:%S'))) - time.timezone
Ruby	Time.local(year, month, day, hour, minute, second, usec ) (or Time.gm for GMT/UTC input). To display add .to_i
Perl	Use the Perl Epoch routines
Java	long epoch = new java.text.SimpleDateFormat("MM/dd/yyyy HH:mm:ss").parse("01/01/1970 01:00:00").getTime() / 1000;
VBScript/ASP	DateDiff("s", "01/01/1970 00:00:00", time field)
AutoIT	_DateDiff('s', "1970/01/01 00:00:00", "YYYY/MM/DD HH:MM:SS")
Delphi	Epoch := DateTimeToUnix(StrToDateTime(myString));
C	Use the C Epoch Converter routines
R	as.numeric(as.POSIXct("MM/dd/yyyy HH:mm:ss", origin="1970-01-01"))
MySQL	SELECT unix_timestamp(time) Time format: YYYY-MM-DD HH:MM:SS or YYMMDD or YYYYMMDD More on using Epoch timestamps with MySQL
PostgreSQL	SELECT extract(epoch FROM date('2000-01-01 12:34')); With timestamp: SELECT EXTRACT(EPOCH FROM TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-08'); With interval: SELECT EXTRACT(EPOCH FROM INTERVAL '5 days 3 hours');
SQLite	SELECT strftime('%s',timestring);
SQL Server	SELECT DATEDIFF(s, '1970-01-01 00:00:00', time field)
JavaScript	Use the JavaScript Date object
Unix/Linux Shell	date +%s -d"Jan 1, 1980 00:00:01" Replace '-d' with '-ud' to input in GMT/UTC time.

 

Convert from epoch to human readable date

PHP	date(output format, epoch); Output format example: 'r' = RFC 2822 date
Python	import time first, then time.strftime("%a, %d %b %Y %H:%M:%S +0000", time.localtime(epoch)) Replace time.localtime with time.gmtime for GMT time.
Ruby	Time.at(epoch)
Perl	Use the Perl Epoch routines
Java	String date = new java.text.SimpleDateFormat("MM/dd/yyyy HH:mm:ss").format(new java.util.Date (epoch*1000));
VBScript/ASP	DateAdd("s", epoch, "01/01/1970 00:00:00")
AutoIT	_DateAdd("s", $EpochSeconds , "1970/01/01 00:00:00")
Delphi	myString := DateTimeToStr(UnixToDateTime(Epoch)); Where Epoch is a signed integer.
C	Use the C Epoch Converter routines
Objective-C	NSDate * myDate = [NSDate dateWithTimeIntervalSince1970:epoch]; NSLog(@"%@", date);
R	as.POSIXct(epoch, origin="1970-01-01", tz="GMT")
MySQL	FROM_UNIXTIME(epoch, optional output format) Default output format is YYY-MM-DD HH:MM:SS. If you need support for negative timestamps: DATE_FORMAT(DATE_ADD(FROM_UNIXTIME(0), interval -315619200 second),"%Y-%m-%d") (replace -315619200 with epoch)
PostgreSQL	PostgreSQL version 8.1 and higher: SELECT to_timestamp(epoch);  Older versions: SELECT TIMESTAMP WITH TIME ZONE 'epoch' + epoch * INTERVAL '1 second';
SQLite	SELECT datetime(epoch_to_convert, 'unixepoch'); or local timezone: SELECT datetime(epoch_to_convert, 'unixepoch', 'localtime');
Oracle PL/SQL	SELECT to_date('01-JAN-1970','dd-mon-yyyy')+(1326357743/60/60/24) from dual Replace 1326357743 with epoch.
SQL Server	DATEADD(s, epoch, '1970-01-01 00:00:00')
Microsoft Excel	=(A1 / 86400) + 25569 Format the result cell for date/time, the result will be in GMT time (A1 is the cell with the epoch number). For other time zones: =((A1 +/- time zone adjustment) / 86400) + 25569.
Crystal Reports	DateAdd("s", {EpochTimeStampField}-14400, #1/1/1970 00:00:00#) -14400 used for Eastern Standard Time. See Time Zones.
JavaScript	Use the JavaScript Date object
Tcl/Tk	clock format 1325376000
Unix/Linux Shell	date -d @1190000000 Replace 1190000000 with your epoch, needs recent version of 'date'. Replace '-d' with '-ud' for GMT/UTC time.
PowerShell	Function get-epochDate ($epochDate) { [timezone]::CurrentTimeZone.ToLocalTime(([datetime]'1/1/1970').AddSeconds($epochDate)) }, then use: get-epochDate 1279152364. Works for Windows PowerShell v1 and v2
Other OS's	Command line: perl -e "print scalar(localtime(epoch))" (If Perl is installed) Replace 'localtime' with 'gmtime' for GMT/UTC time.

 

 

 

상기 내용은 여기에...   http://www.epochconverter.com/      웹 페이지에서 epoch 값 과 date 를 바로 converting 할 수 있다.