Re: NetBSD-10.0_BETA: clock: unknown CMOS layout

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Fri, 23 Dec 2022 10:20:27 -0000 (UTC)
    From:        mlelstv%serpens.de@localhost (Michael van Elst)
    Message-ID:  <to3vdb$2bl$1%serpens.de@localhost>

  | The message says that no century information is found in the CMOS RAM,
  | the hardware clock itself seems to keep only 2 year digits. The century
  | is then deduced as 1900 if the year number is less than 70 and 2000
  | otherwise.

I would hope that it is the other way around, if >=70, assume 1900,
and if < 70, assume 2000 (which is why 22 now will produce 2022).

  | This heuristic will fail 2030.

2070 would be more likely.    But given how very unlikely it is now
that anyone is ever going to (legitimately - people doing weird things
can deal with the issues) boot a system in the 20th century, ever again,
then perhaps we should be altering the heuristic to assume all years
are 21st century for now, and then in another 50 years or so, if systems
still exist with this issue, and we are still measuring civil time the same
way, change the heuristic again so that 22nd century years will work
with a similar boundary to what was used for 20th/21st century years,
until sometime into the 22nd century, where it can start assuming all
boots occur in that period (and so on, for as long as this is needed).

kre