Re: unable to set time very far in the future

[David Brownlee <abs%absd.org@localhost>]

On Sun, 16 Oct 2022 at 15:34, Jan Schaumann <jschauma%netmeister.org@localhost> wrote:
>
> RVP <rvp%SDF.ORG@localhost> wrote:
> > On Sat, 15 Oct 2022, Jan Schaumann wrote:
> >
> > > - I just can't _set_ the clock to any value above
> > > 68719476736.  Anybody know why?
> > >
> >
> > There is a check in the kernel. In sys/kern/kern_time.c:
> >
> >     190         /*
> >     191          * The time being set to an unreasonable value will cause
> >     192          * unreasonable system behaviour.
> >     193          */
> >     194         if (ts->tv_sec < 0 || ts->tv_sec > (1LL << 36))
> >     195                 return EINVAL;
> >
> > And, `date 414708200732.17' == (1<<36) + 1 secs.
>
> Cool, thanks!
>
> Do we have examples of what this "unreasonable system
> behaviour" might be, and how we ended up picking this
> particular value?

Absent any functional change, could we factor this out to a #define
for future code spelunkers?

Possibly switching to a more human friendly number such as 4000AD (or
4004AD if we port NetBSD to the spindizzy)

David