adjday
return !val || adjday(t, '+', val, mk);
return !val || adjday(t, '-', val, mk);
return adjday(t, '-', t->tm_wday - val, mk);
return adjday(t, '+', val - t->tm_wday, mk);
if (!adjday(t, '+', days, 0))
if (!adjday(t, '-', days, 0))
if (!adjday(t, type, val, 1))