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.
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 <...