// 系统开机时间(毫秒)
+ (int) getSystemUptimeByMillisecond {
const int64_t kOneMillion = 1000 * 1000;
static mach_timebase_info_data_t s_timebase_info;
if (s_timebase_info.denom == 0) {
(void) mach_timebase_info(&s_timebase_info);
}
return (int)((mach_absolute_time() * s_timebase_info.numer) / (kOneMillion * s_timebase_info.denom));
}