使用C的库函数获取当前本地时间

1. tm结构体

struct tm {
inttm_sec;
/* seconds after the minute [0-60] */

int tm_min;/* minutes after the hour [0-59] */

int tm_hour;/* hours since midnight [0-23] */

int tm_mday;/* day of the month [1-31] */

int tm_mon;/* months since January [0-11] */

int tm_year;/* years since 1900 */

int tm_wday;/* days since Sunday [0-6] */

int tm_yday;/* days since January 1 [0-365] */

int tm_isdst;/* Daylight Savings Time flag */

long tm_gmtoff;/* offset from CUT in seconds */

char *tm_zone;/* timezone abbreviation */

};

2. 使用localtime获取本地时间，具体代码如下

//获取当前时间，采用C的库函数，返回值不需要外部释放，效率方面比使用OC的NSDate类高效3-4倍

- (struct tm*)getTime

{

//时间格式

struct timeval ticks;

gettimeofday(&ticks, nil);

time_t now;

struct tm* timeNow;

time(&now);

timeNow = localtime(&now);

timeNow->tm_gmtoff = ticks.tv_usec/1000; //毫秒



timeNow->tm_year += 1900; //tm中的tm_year是从1900至今数

timeNow->tm_mon += 1; //tm_mon范围是0-11



return timeNow;

}