Timestamp - confusion with daylight saving time


 
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# 1  
Timestamp - confusion with daylight saving time

Hello!
I'm currently working on a climatological dataset that uses unix-timestamp and a real date like 28/03/2004 02:45:00 h. in spring the unix-timestamp follows its continuos mode but in the column of the real date the time jumps one hour forward (e.g. from 1:59:59 to 3:00:00). i think this is ok if the real time would show central european daylight saving time.
BUT:
in autumn the unix-timestamp follows further its continuous mode and the real time as well: i.e. that the time does not step back again one hour.
in the next spring the real time jumps again one hour forward.
Wouldn't this mean that my data loses every year one hour in spring?
Has anyone an excel-tool that enables me to verify the to different datasets while beeing sure that the real time does not change when daylight saving time is usually applied?

thanks in advance
# 2  
Quote:
Originally Posted by softmachine
in autumn the unix-timestamp follows further its continuous mode and the real time as well: i.e. that the time does not step back again one hour.
Excuse me?

Code:
$ cat timetool.c
#include <stdlib.h>
#include <time.h>

main(argc,argv)
char **argv;
{
        long start, now;
        char buff[100];
        struct tm *tm;
        start=atoi(argv[1]);
        for(now=start; now < (start + 18 * 600); now+=600) {
                tm=localtime(&now);
                strftime(buff,100, "%A  %b %e, %Y  %H:%M %Z", tm);
                printf(" %13d   =  %s \n", now, buff);
        }

}
$ ./timetool 1130647000
    1130647000   =  Sunday  Oct 30, 2005  00:36 EDT
    1130647600   =  Sunday  Oct 30, 2005  00:46 EDT
    1130648200   =  Sunday  Oct 30, 2005  00:56 EDT
    1130648800   =  Sunday  Oct 30, 2005  01:06 EDT
    1130649400   =  Sunday  Oct 30, 2005  01:16 EDT
    1130650000   =  Sunday  Oct 30, 2005  01:26 EDT
    1130650600   =  Sunday  Oct 30, 2005  01:36 EDT
    1130651200   =  Sunday  Oct 30, 2005  01:46 EDT
    1130651800   =  Sunday  Oct 30, 2005  01:56 EDT
    1130652400   =  Sunday  Oct 30, 2005  01:06 EST
    1130653000   =  Sunday  Oct 30, 2005  01:16 EST
    1130653600   =  Sunday  Oct 30, 2005  01:26 EST
    1130654200   =  Sunday  Oct 30, 2005  01:36 EST
    1130654800   =  Sunday  Oct 30, 2005  01:46 EST
    1130655400   =  Sunday  Oct 30, 2005  01:56 EST
    1130656000   =  Sunday  Oct 30, 2005  02:06 EST
    1130656600   =  Sunday  Oct 30, 2005  02:16 EST
    1130657200   =  Sunday  Oct 30, 2005  02:26 EST
$

 

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