Demo of thread reclamation crashes w/o hooking world/Del

test.cpp

#include <thread>
#include <memory>
#include <atomic>

using namespace std;
using namespace std::chrono_literals;

atomic<bool> should_quit;

struct wrapper {
	thread th;
	wrapper(thread&& th) : th(move(th)) {}
	~wrapper() { should_quit.store(true); th.join(); }
};

unique_ptr<wrapper> handle;
atomic<int> message;

extern "C" const char* start() {
	handle = make_unique<wrapper>(thread([](){
		for (int i = 1; i < 10; ++i) {
			message.store(i);
			this_thread::sleep_for(1s);
			if (should_quit.load()) {
				return;
			}
		}
		message.store(-1);
	}));
	return "";
}

extern "C" const char* update() {
	static char buf[128];
	int msg = message.load();
	if (msg == 0) {
		return "...";
	} else if (msg == -1) {
		return "";
	} else {
		message.store(0);
		sprintf(buf, "%d", msg);
		return buf;
	}
}

extern "C" const char* stop() {
	handle.reset();
	return "";
}

test.dm

#define DLL @"test.dll"

/client/verb/Go()
	src << "starting"
	call(DLL, "start")()
	var/r
	while ((r = call(DLL, "update")()))
		if (r != "...")
			src << "progress: [r]"
		sleep (1)
	src << "done"

/client/verb/Reboot_Badly()
	world.Reboot()

/client/verb/Reboot_Safely()
	call(DLL, "stop")()
	world.Reboot()