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digitalmars.D.learn - Unable to set static data member of a class (results in default value

reply Enjoys Math <enjoysmath gmail.com> writes:
I have:

class DataSignal : Thread
{
public:
    static int dataReadDelay;

    void run() {
        while (true) {
            Thread.sleep(dur!"msecs"(dataReadDelay));
            // Read in the new file data
        }
    }
}


in main I have:

DataSignal.dataReadDelay = 8000;

// initialize a bunch of signals


Then when each thread is running they sleep for 0 seconds, and I 
can verify that dataReadDelay is staying at 0.  I have 
initialized it no where else.  This seems like a major bug.
Aug 27 2017
parent reply Adam D. Ruppe <destructionator gmail.com> writes:
On Sunday, 27 August 2017 at 22:21:11 UTC, Enjoys Math wrote:

    static int dataReadDelay;


That's thread-local. Use shared to make it shared across all 
threads, and/or initialize it in the same thread as the use.


See:
https://dlang.org/migrate-to-shared.html
https://tour.dlang.org/tour/en/multithreading/thread-local-storage
Aug 27 2017
parent Jonathan M Davis via Digitalmars-d-learn writes:
On Sunday, August 27, 2017 22:29:46 Adam D. Ruppe via Digitalmars-d-learn 
wrote:

 On Sunday, 27 August 2017 at 22:21:11 UTC, Enjoys Math wrote:

    static int dataReadDelay;


 That's thread-local. Use shared to make it shared across all
 threads, and/or initialize it in the same thread as the use.


 See:
 https://dlang.org/migrate-to-shared.html
 https://tour.dlang.org/tour/en/multithreading/thread-local-storage


Yeah, so the thread with main in it should have the value set, but for every
other thread, it would be default-initialized. If you're just looking to set
it that one value for all threads and not change it, I'd suggest that you
just set it directly and make it immutable - or use enum, so it's a manifest
constant. If you want to change it though, you will need to use shared and
deal with protecting it appropriately when accessing it.

- Jonathan M Davis
Aug 27 2017