SECDAY
clock_secs_to_ymdhms(reg * SECDAY, &dt);
SXICMS4(sc, sc->sc_yymmdd, 0xffff, tv->tv_sec / SECDAY);
days = secs / SECDAY;
rsec = secs % SECDAY;
if (deltat < 2 * SECDAY)
(long long)(deltat / SECDAY));
#define SECYR (SECDAY * 365)