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Comment by gpderetta

12 hours ago

You can go full circle and also make operations on a mutex asynchronous. Hence the realization that message passing and shared memory are truly dual.

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gpderetta

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mgaunard  12 hours ago

The very idea of a mutex is that it is synchronous. You wait until you can acquire the mutex.

If it's asynchronous, it's not a mutex anymore, or it's just used to synchronously setup some other asynchronous mechanism.

  • gpderetta  11 hours ago

    A mutex is a way to guarantee mutual exclusion nothing more nothing less; You can recover synchronous behaviour if you really want:

        synchronized<Something> something;
    ...
    co_await something.async_visit([&](Something& x) {
        /* critical section here */ 
    });

    • mgaunard  10 hours ago

      that isn't a mutex, that's delegating work asynchronously and delegating something else to run when it is complete (the implicitly defined continuation through coroutines).

      In systems programming parlance, a mutex is a resource which can be acquired and released, acquired exactly once, and blocks on acquire if already acquired.

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