lock_guard加锁

#include <iostream>
#include <mutex>
#include <thread>

void msg_func()
{
   std::mutex mutex;

   while(1)
   {
      std::lock_guard<std::mutex> guard(mutex);

      std::cout << "do something" << std::endl;

      std::chrono::milliseconds second(1000);
      std::this_thread::sleep_for(second);
   }
}

int main()
{
   std::thread mythread(&msg_func);
   getchar();

   return 0;
}

$ g++ lock_guard.cpp -std=c++11 -pthread

$ ./a.out 
do something
do something