#include <time.h>

time_t time(time_t *t);

#include <time.h>
main(){
  int seconds = time((time_t*)NULL);
  printf("%d\n", seconds);
}

9.73E+08

#include <time.h>

struct tm *gmtime(const time_t *timep);

struct tm{
  int tm_sec; //代表目前秒數(shù), 正常范圍為0-59, 但允許至61 秒
  int tm_min; //代表目前分?jǐn)?shù), 范圍0-59
  int tm_hour; //從午夜算起的時(shí)數(shù), 范圍為0-23
  int tm_mday; //目前月份的日數(shù), 范圍01-31
  int tm_mon; //代表目前月份, 從一月算起, 范圍從0-11
  int tm_year; //從1900 年算起至今的年數(shù)
  int tm_wday; //一星期的日數(shù), 從星期一算起, 范圍為0-6
  int tm_yday; //從今年1 月1 日算起至今的天數(shù), 范圍為0-365
  int tm_isdst; //日光節(jié)約時(shí)間的旗標(biāo)
};

#include <time.h>
main(){
  char *wday[] = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
  time_t timep;
  struct tm *p;
  time(&timep);
  p = gmtime(&timep);
  printf("%d%d%d", (1900+p->tm_year), (1+p->tm_mon), p->tm_mday);
  printf("%s%d;%d;%d\n", wday[p->tm_wday], p->tm_hour, p->tm_min, p->tm_sec);
}

2000/10/28 Sat 8:15:38