shared_mutex

README.md

< C++17

run shared_mutex.cc -lboost_system -lboost_thread -lpthread -std=c++14

C++17

CXX=g++-6 run shared_mutex.cc -lpthread -std=c++17

shared_mutex.cc

#include <chrono>
#include <thread>

#if __cplusplus > 201402L
#include <shared_mutex>
#else
#include <boost/thread/shared_mutex.hpp>
#endif

#if __cplusplus > 201402L
std::shared_mutex m;
#else
boost::shared_mutex m;
#endif

bool running = true;
int x = 0;

void read() {
#if __cplusplus > 201402L
	std::shared_lock<std::shared_mutex> lock(m);
#else
	boost::shared_lock<boost::shared_mutex> lock(m);
#endif
	printf("starting reading\n");
	printf("%d\n", x);
	printf("ending reading\n");
}

void write() {
#if __cplusplus > 201402L
	std::unique_lock<std::shared_mutex> lock(m);
#else
	boost::unique_lock<boost::shared_mutex> lock(m);
#endif
	printf("starting writing\n");
	x++;
	printf("ending writing\n");
}

int main() {
	printf("__cplusplus: %ld\n", __cplusplus);

	std::thread read_thread([]() {
		while (running) {
			read();
			std::this_thread::sleep_for(std::chrono::seconds(1));
		}
	});

	std::thread write_thread([]() {
		while (running) {
			write();
			std::this_thread::sleep_for(std::chrono::seconds(2));
		}
	});

	std::this_thread::sleep_for(std::chrono::seconds(10));

	running = false;
	read_thread.join();
	write_thread.join();
	printf("OK\n");
}