book: reword timer bit

This commit is contained in:
Darin Morrison 2015-03-31 14:14:04 -06:00
parent 80bf31dd51
commit 9ba7974b35

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@ -280,13 +280,15 @@ it returns an `Result<T, E>`, and because this is just an example, we `unwrap()`
it to get a reference to the data. Real code would have more robust error handling
here. We're then free to mutate it, since we have the lock.
This timer bit is a bit awkward, however. We have picked a reasonable amount of
time to wait, but it's entirely possible that we've picked too high, and that
we could be taking less time. It's also possible that we've picked too low,
and that we aren't actually finishing this computation.
Lastly, while the threads are running, we wait on a short timer. But
this is not ideal: we may have picked a reasonable amount of time to
wait but it's more likely we'll either be waiting longer than
necessary or not long enough, depending on just how much time the
threads actually take to finish computing when the program runs.
Rust's standard library provides a few more mechanisms for two threads to
synchronize with each other. Let's talk about one: channels.
A more precise alternative to the timer would be to use one of the
mechanisms provided by the Rust standard library for synchronizing
threads with each other. Let's talk about one of them: channels.
## Channels