Calculate date based on another date + number of minutes

[Golan]

Hi all,

I need to write a code which gets a date (in format 'YYYYMMDDhh24MISS')
and number of seconds (X), and returns the date (again in format
'YYYYMMDDHH24MISS') that is X seconds prior to the first date.
Any ideas?

Thanks in advance

 

[Richard Heathfield]

Golan said:

Hi all,

I need to write a code which gets a date (in format 'YYYYMMDDhh24MISS')
and number of seconds (X), and returns the date (again in format
'YYYYMMDDHH24MISS') that is X seconds prior to the first date.
Any ideas?

I suggest you take a long hard look at the standard library functions
prototyped in <time.h>, and then attempt a solution of your own. If you get
stuck, post your best-effort code and maybe we can help you fix it.

 

[Frederick Gotham]

Golan posted:

Hi all,

I need to write a code which gets a date (in format 'YYYYMMDDhh24MISS')
and number of seconds (X), and returns the date (again in format
'YYYYMMDDHH24MISS') that is X seconds prior to the first date.
Any ideas?

Thanks in advance

Well you might want to start by using half a brain cell and breaking the
string up:

#include <string.h>

void Process(char const *p)
{
char year[4+1],month[2+1],day[2+1],
hour[2+1],hour_type[2+1],mins[2+1],secs[2+1];

#define SIZE(arr) (sizeof(arr)/sizeof*(arr))

#define COPY_ADV(x) (\
memcpy((x),p,SIZE((x))-1) \
, (x)[SIZE((x))-1] = 0 \
, p += SIZE((x))-1 )


COPY_ADV(year);
COPY_ADV(month);
COPY_ADV(day);
COPY_ADV(hour);
COPY_ADV(hour_type);
COPY_ADV(mins);
COPY_ADV(secs);

/* Now do some more stuff */

#undef SIZE
#undef COPY_ADV
}

 

[dcorbit]

Hi all,

I need to write a code which gets a date (in format 'YYYYMMDDhh24MISS')
and number of seconds (X), and returns the date (again in format
'YYYYMMDDHH24MISS') that is X seconds prior to the first date.
Any ideas?

Thanks in advance

http://sourceforge.net/projects/aptimelib
http://sourceforge.net/projects/yest
http://sourceforge.net/projects/jday

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Others go down to the wheel store and buy a shiny new wheel.

I just traipse on over to Sourceforge. They're giving wheels away.