command line > date +%j

[cassie99]

Hello.

My dilemma:
I would like to create a function that returns the UNIX system date with a julian day format (date +%j). Since it doesn't look like I can use:

int jul;
jul=system("date +%j"
return jul;

Any ideas on what I could use to make this work? Thanks in advance.

Cassie

 

[newmangj]

What about the following code snippet...

#include <time.h>

int get_julian()
{
static int julian;
struct tm * ttm;
time_t t;

t=time(NULL);
ttm=localtime(&t);
julian=(((ttm->tm_year+1900)%100)*1000)+(ttm->tm_yday+1);
return julian;
}


Cheers - Gavin

 

[cassie99]

Thanks Gavin. Your post is very similar to what I ended up using.

//get julian day
int getJulianDay()
{
time_t d1;
struct tm *f;
time(&d1);

f = localtime(&d1);
int jul;
jul = (f->tm_yday)+1;
return jul;
}

Regards,
Cassie