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Embedded Programming with Modern C++

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Understand how to coordinate multiple threads in a C++ program by using condition variables to wait and notify threads. Learn the roles of std::unique_lock and std::lock_guard, how to check predicates safely, and manage complex waiting workflows to ensure proper synchronization in concurrent programming.

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Example

C++
// conditionVariable.cpp
#include <iostream>
#include <condition_variable>
#include <mutex>
#include <thread>
std::mutex mutex_;
std::condition_variable condVar;
bool dataReady{false};
void doTheWork(){
  std::cout << "Processing shared data." << std::endl;
}
void waitingForWork(){
    std::cout << "Worker: Waiting for work." << std::endl;
    std::unique_lock<std::mutex> lck(mutex_);
    condVar.wait(lck, []{ return dataReady; });
    doTheWork();
    std::cout << "Work done." << std::endl;
}
void setDataReady(){
    {
      std::lock_guard<std::mutex> lck(mutex_);
      dataReady = true;
    }
    std::cout << "Sender: Data is ready."  << std::endl;
    condVar.notify_one();
}
int main(){
  std::cout << std::endl;
  std::thread t1(waitingForWork);
  std::thread t2(setDataReady);
  t1.join();
  t2.join();
  std::cout << std::endl;
  
}

Explanation

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