Not having read the C++ synchronisation primitives before, this async task queue is probably incorrect. But nevertheless, let's have a quick go at employing it — in a hideously thread unsafe fashion — for audio generation. What can possibly go wrong?

Concurrency/AsyncTaskQueue.hpp

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+//
+//  AsyncTaskQueue.hpp
+//  Clock Signal
+//
+//  Created by Thomas Harte on 07/10/2016.
+//  Copyright © 2016 Thomas Harte. All rights reserved.
+//
+
+#ifndef AsyncTaskQueue_hpp
+#define AsyncTaskQueue_hpp
+
+#include <memory>
+#include <thread>
+#include <list>
+#include <condition_variable>
+
+namespace Concurrency {
+
+class AsyncTaskQueue {
+
+	public:
+		AsyncTaskQueue();
+		~AsyncTaskQueue();
+
+		void enqueue(std::function<void(void)> function);
+		void synchronise();
+
+	private:
+		std::unique_ptr<std::thread> thread_;
+
+		std::mutex queue_mutex_;
+		std::list<std::function<void(void)>> pending_tasks_;
+		std::condition_variable processing_condition_;
+		bool should_destruct_;
+};
+
+}
+
+#endif /* Concurrency_hpp */