Blocking Issues

To make my point clear, you have to use a condition variable in combination with a predicate. If you don’t, your program may become a victim of a spurious wakeup or lost wakeup.

If you use a condition variable without a predicate, the notifying thread may send its notification before the waiting thread is waiting. Therefore, the waiting thread waits forever. This phenomenon is called a lost wakeup.

Here is the program.

Blocking condition variables

 1 // conditionVariableBlock.cpp
 2 
 3 #include <iostream>
 4 #include <condition_variable>
 5 #include <mutex>
 6 #include <thread>
 7 
 8 std::mutex mutex_;
 9 std::condition_variable condVar;
10 
11 bool dataReady;
12 
13 
14 void waitingForWork(){
15 
16     std::cout << "Worker: Waiting for work." << std::endl;
17 
18     std::unique_lock<std::mutex> lck(mutex_);
19     condVar.wait(lck);                          
20     // do the work
21     std::cout &lt...