MAX_POSIX_TIME
CTASSERT(MAX_POSIX_TIME <= INT64_MAX - INT_MAX * SECS_PER_DAY);
CTASSERT((MAX_POSIX_TIME - MIN_POSIX_TIME) / SECS_PER_DAY <= INT_MAX);
return MIN_POSIX_TIME <= time && time <= MAX_POSIX_TIME;