>Monotonic clocks are guaranteed to not go backward. A sudden warp 35
>seconds into the future when you have timers set for 15 and 20
>seconds into the future is still ugly....
I don't have the POSIX specs handy, but I see no reason we could not let
it use a warpless monotonic clock.
The problem of timeouts going wild when time is being warped applies
to syscalls using relative timeouts as well. Even when a relative
timeout is wanted, it is usually transformed (via gettimeofday or
similar) to an absolute timeout:
T = some_clock() + dT
timeout = dT
loop:
poll(..., timeout)
if (poll did not time out):
now = some_clock()
timeout = MAX(0, T - now)
goto loop
This kind of code is very common, because the timeout is usually the
time to some event in the future. If some_clock() is subject to
warping (which is the case when gettimeofday() is used), then you have
the problem again.
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