Method set

src/fl/channels/driver.h:106–113

        }

        void set(PollNeededCallback callback) FL_NOEXCEPT {
            if (callback.callback == nullptr) {
                clear();
                return;
            }
            Snapshot* snapshot = new Snapshot(callback); // ok bare allocation
            retire(mSnapshot.exchange(snapshot, fl::memory_order_acq_rel));
        }

        void clear() FL_NOEXCEPT {
            retire(mSnapshot.exchange(nullptr, fl::memory_order_acq_rel));