Simon Kelley <simon@thekelleys.org.uk> writes:

> That would be possible: it would require care to make it work in the
> face of the system time being warped by NTP. Best way may  be to use
> times() rather than time()

Good point. Since the availability of reliable time is what we're
waiting for, perhaps a large jump in the system clock could be taken to
mean it has been achieved and taken as a signal to exit the grace
period? With a timer for the case where the time is already accurate, of
course. This would make it rather specific to this use case, though...

-Toke