Getting the current timestamp in C

The following program is used for getting the timestamp in C

#include <stdio.h>

#include <time.h>

int main ()

{

  time_t rawtime;

  struct tm * timeinfo;

  time ( &rawtime );

  timeinfo = localtime ( &rawtime );

  printf ( "Current local time and date: %s", asctime (timeinfo) );

  return 0;

}

struct tm is defined in time.h .It has the following fields:

struct tm {
int tm_sec; /* Seconds (0-60) */
int tm_min; /* Minutes (0-59) */
int tm_hour; /* Hours (0-23) */
int tm_mday; /* Day of the month (1-31) */
int tm_mon; /* Month (0-11) */
int tm_year; /* Year - 1900 */
int tm_wday; /* Day of the week (0-6, Sunday = 0) */
int tm_yday; /* Day in the year (0-365, 1 Jan = 0) */
int tm_isdst; /* Daylight saving time */
};

localtime is used to convert the information which is present in rawtime structure to structure tm.rawtime structure has the value which is equal to number of seconds elapsed from 1970-01-01.

asctime converts the structure tm into a null terminated string