Question

time.h中如何调用系统时间？

例如我要知道现在几点，不打印其他；
打印星期，不打印其他；。。。。

Answer 1

time_t nTimer = time(NULL);
struct tm *pTm = localtime(nTimer);

tm 结构里保存了时间的各种信息（年月日时分秒等）
The fields of the structure type tm store the following values, each of which is an int:
tm_sec

Seconds after minute (0 – 59).
tm_min

Minutes after hour (0 – 59).
tm_hour

Hours after midnight (0 – 23).
tm_mday

Day of month (1 – 31).
tm_mon

Month (0 – 11; January = 0).
tm_year

Year (current year minus 1900).
tm_wday

Day of week (0 – 6; Sunday = 0).
tm_yday

Day of year (0 – 365; January 1 = 0).
tm_isdst

Positive value if daylight saving time is in effect; 0 if daylight saving time is not in effect; negative value if status of daylight saving time is unknown. If the TZ environment variable is set, the C run-time library assumes rules appropriate to the United States for implementing the calculation of daylight-saving time (DST).