daysinmonth
lmdays = daysinmonth(t);
daycount = daysinmonth(t);
t->tm_mday = daysinmonth(t);
if (val > 0 && val <= daysinmonth(t))
days += daysinmonth[m-1];
ml = daysinmonth[m];
static const u_char daysinmonth[] = {31,28,31,30,31,30,31,31,30,31,30,31};