0x01 主要涉及对象
- struct timespec
struct timespec
{
__time_t tv_sec; /* Seconds. */
__syscall_slong_t tv_nsec; /* Nanoseconds. */
};
- struct tm
struct tm
{
int tm_sec; /* Seconds. [0-60] (1 leap second) */
int tm_min; /* Minutes. [0-59] */
int tm_hour; /* Hours. [0-23] */
int tm_mday; /* Day. [1-31] */
int tm_mon; /* Month. [0-11] */
int tm_year; /* Year - 1900. */
int tm_wday; /* Day of week. [0-6] */
int tm_yday; /* Days in year.[0-365] */
int tm_isdst; /* DST. [-1/0/1]*/
# ifdef __USE_MISC
long int tm_gmtoff; /* Seconds east of UTC. */
const char *tm_zone; /* Timezone abbreviation. */
# else
long int __tm_gmtoff; /* Seconds east of UTC. */
const char *__tm_zone; /* Timezone abbreviation. */
# endif
};
- localtime_r
完成 tm 向 timespec 的转换
0x02 使用例:
#include <sys/stat.h>
#include <time.h>
char *cc_time_2_str(struct timespec ts) {
struct tm t;
char *buf = (char *) malloc(64);
strftime(buf, 64, "%Y-%m-%d %H:%M:%S", localtime_r(&ts.tv_sec, &t));
return buf;
}
struct timespec *cc_get_system_time() {
struct timespec *curr_time = (struct timespec *) malloc(sizeof(struct timespec));
if (clock_gettime(CLOCK_REALTIME, curr_time) != 0)
exit(1);
return curr_time;
}
int main(int argc, char *argv[]) {
struct timespec *now = cc_get_system_time();
char *now_str = cc_time_2_str(*now);
printf("time now is %s\n", now_str);
free(now_str);
free(now);
exit(0);
}
为了方便使用, 函数设计时,还是习惯在函数内部返回一个malloc 指针, 外部 free 即可.
