How to convert epoch time to year

Question

I have time in epoch format.
I just want to retrieve Year from it.

how should we do it in c or c++ ?

Actually i have time since epoch in seconds and i need to calculate age depending on it.
So input will be seconds since epoch and out put should be Age based on current date.

Thanks,
PP.

Answer 1

Using the gmtime or localtime functions to convert the time_t to a struct tm. Then you can use the tm_year field of the struct to get the year.

Or for offline use, you can use a web converter, like this.

Edit:

Sample code:

time_t nowEpoch = time(NULL);
struct tm* nowStruct = gmtime(&nowEpoch);
int year = nowStruct->tm_year + 1900;

Answer 2

In C timestamps (ie: seconds from epoch) are usually stored in time_t, while human-wise dates are stored in structure tm. You need a function that converts time_ts in tms.

gmtime or localtime are two C standard function that do your job.

struct tm *date = gmtime( your_time );
printf( "Year = %d\n", date->tm_year );

Warning that these functions are not thread-safe. You'll find a reentrant version on POSIX systems (linux, mac os x, ...): gmtime_r and localtime_r