linux 獲取當前時間，精確到毫秒

void sysTime(void)
{
 struct timeval tv;
 struct timezone tz;
 struct tm *t;
 
 gettimeofday(&tv, &tz);




 t = localtime(&tv.tv_sec);




 printf("time_now:%d-%d-%d %d:%d:%d.%ld
", 1900+t->tm_year, 1+t->tm_mon, t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec, tv.tv_usec);
}