Async messages to a thread.

[John Colvin]

On Monday, 29 July 2013 at 16:19:03 UTC, lindenk wrote:
>> void foo(Tid parent) {
>>    bool run = true;
>>    while(run)
>>    {
>>         //do_some_blocking_function();
>>         receiveTimeout(dur!"msecs"(0),
>>             (string s){if(s == "STAHP!") run = false;}
>>         );
>>    }
>>
>>    // clean up
>>    send(parent, "done");
>> }
>>
>>
>> void main()
>> {
>>    auto tid = spawn(&foo, thisTid);
>>
>>    // do stuff / wait for some condition
>>
>>    send(tid, "STAHP!");
>>    auto msg = receiveOnly!(string)();
>>    assert(msg == "done");
>> }
>
> Ah, no I mean, what if do_some_blocking_function blocks for 
> some indeterminate amount of time. I would like it to exit even 
> when it is currently blocking (as it could be unpredictable 
> when it will stop blocking).

The blocking function could start in a new thread and do a 
receiveTimeout periodically, or you could make it stateful (if 
necessary) and return periodically and be restarted if it hasn't 
been asked to stop (which is just a very ugly and rudimentary 
version of what you'd want to do with fibers).

Or, if you don't care about making a mess, just kill the thread I 
guess.