SECS_PER_MIN
tmp->tm_min = (int)(rem / SECS_PER_MIN);
tmp->tm_sec = (int)(rem % SECS_PER_MIN);
#define SECS_PER_HOUR (SECS_PER_MIN * 60)
dtime->ts_min = sec / SECS_PER_MIN;
sec -= dtime->ts_min * SECS_PER_MIN;