Boost中的多个读者,单个写入器锁

#include<boost/thread.hpp>
#include<iostream>
#include<vector>

boost::shared_mutex m;
std::vector<int> v;

void reader() {
    boost::shared_lock<boost::shared_mutex> lock(m);
    std::cout << "Reader: " << v.size()<< std::endl;
}

void writer() {
    boost::unique_lock<boost::shared_mutex> lock(m);
    v.push_back(42);
    std::cout << "Writer: " << v.size()<< std::endl;
}

int main() {
    boost::thread_group group;

    for (int i = 0; i < 10; ++i) {
        group.create_thread(reader);
    }

    group.create_thread(writer);
    group.join_all();

    return 0;
}