Is it OK to modify _TOD_Ticks_per_second?

Joel Sherrill <> joel.sherrill at
Tue Mar 9 20:50:51 UTC 2004

Till Straumann wrote:
> I'm thinking about synchronizing the system clock
> with NTP. One obvious method which avoids leaps
> back in time would be letting a feedback loop
> control the clock tick rate.
> There is no API to set the system clock rate.
> Do you think it would be easy to add one to
> set _TOD_Ticks_per_second? Or are there silent
> assumptions that the clock rate never changes
> (even by small amounts)?

find . -type f | xargs -e grep TOD_Ticks_per_second

shows that it is only used a handful of places and
I think it is OK.  There is a chance some math
on alarm or ualarm might be negatively impacted but
the risk looks minor.

> -- Till

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