boost 实现读写锁

#include <boost/thread/shared_mutex.hpp>
#include <boost/thread/locks.hpp>

using BoostMutexWR = boost::shared_mutex;
using BoostLockW = boost::unique_lock<BoostMutexWR>;
using BoostLockR = boost::shared_lock<BoostMutexWR>;

void usingLockWR()
{
    BoostMutexWR m_bstm;    // 创建一个互斥对象

    // 1. 加读锁，对象析构时自动释放锁资源
    {
        BoostLockR lockR(m_bstm);
    }

    // 2. 加写锁，对象析构时自动释放锁资源
    {
        BoostLockW lockW(m_bstm);
    }
}