What does boost::condition_variable::timed_wait() return on spurious wakeups?

Question

Returns: false if the call is returning because the time specified by abs_time was reached, true otherwise.

But what is returned if there is a spurious wakeup?

Yes :-) It is just that it seems to return false for me. I was wondering if anybody has actually observed what happens. — Torleif, Jan 12 '11 at 14:51
The wording in the documentation I think is wrong, "natural instinct" tells you that it MUST return false, otherwise the function would yield a false positive (i.e. you'd might think that the condition really had been set). — Robert, Jul 02 '12 at 14:56

score 5 · Accepted Answer · answered Jan 12 '11 at 14:59

5

If the condition variable could figure that it is a spurious wake-up there would be no need to return, would it?

You need to check if the data protected by the mutex and the condition variable has changed to detect a spurious wake-up. The condition variable can not do that for you.

answered Jan 12 '11 at 14:59

Maxim Egorushkin

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Ok, I guess that means that it can return both true or false on a spurious wakeup. – Torleif Jan 13 '11 at 06:42
@Torleif Nope, there are no spurious timeouts. – Maxim Egorushkin Feb 21 '19 at 16:15

What does boost::condition_variable::timed_wait() return on spurious wakeups?

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