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).
source http://www.epochconverter.com/
```js //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 or when cmd line perl -e “print 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 (Tested in Delphi 2010) Epoch := DateTimetoUnix(Now);
//R as.numeric(Sys.time())
//Erlang calendar:datetime_to_gregorian_seconds(calendar:universal_time())-719528243600.
//MySQL SELECT unix_timestamp(now())
//PostgreSQL SELECT extract(epoch FROM now());
//SQLite SELECT strftime(‘%s’, ‘now’);
//Oracle PL/SQL (still using oracle?) 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 (getTime() returns time in milliseconds.) Math.round(new Date().getTime()/1000.0)
//Visual FoxPro (Warning: time zones not handled correctly) DATETIME() - {^1970/01/01 00:00:00}
//Adobe ColdFusion <cfset epochtime=”left(getTickcount(),” 10)=””>
//Tcl/Tk clock seconds
//Unix/Linux Shell date +%s
//PowerShell get-date (get-date).touniversaltime() -uformat “%s” ```</cfset></std::chrono::milliseconds>
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