[ntp:questions] Getting SNTP to accept large corrections

Michael Deutschmann michael at talamasca.ocis.net
Sat Jan 19 03:14:27 UTC 2008

On Thu, 17 Jan 2008, Christopher Nelson wrote:
> It's an embedded system.  The one I manufacture today can have today
> (or this year) in it but I'll never touch it again to change the
> initial time setting.  One thought I had was periodically write the
> time to a file and use that file to initialize the clock at startup
> before using NTP.

If your system uses a 32-bit time_t, you shouldn't have to worry about
this.  If your system hasn't been built yet, obviously it will never
experience a time earlier than 2008-01-19T03:00Z, and it will break anyway
after 2038-01-19T03:14Z.  That should be enough to nail down which NTP era
to use.

(Interesting -- as I write this it is almost exactly 30 years from the
End of Unix Time.)

If you do have 64-bit time_t, why not just read your filesystem's
timestamp on the drift file?

---- Michael Deutschmann <michael at talamasca.ocis.net>

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