What are some examples of using mutex in programming?

What are some examples of using mutex in programming?

Mutex, or mutual exclusion, is used to prevent concurrent access to shared resources. For example, in a multi-threaded application, you can use a mutex to ensure that only one thread can modify a variable at a time.

Can you give me a code example of using a mutex in C++?

Sure! Here's a simple example:

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

std::mutex mtx;
int shared_variable = 0;

void increment() {
    mtx.lock();
    ++shared_variable;
    mtx.unlock();
}

int main() {
    std::thread t1(increment);
    std::thread t2(increment);
    t1.join();
    t2.join();
    std::cout << "Shared Variable: " << shared_variable << std::endl;
}

This code ensures that the shared_variable is safely incremented by multiple threads.

What happens if I forget to unlock the mutex?

If you forget to unlock the mutex, it can lead to a deadlock situation where other threads are unable to access the shared resource, causing your program to hang.

Are there alternatives to using mutex for thread safety?

Yes, alternatives include using read-write locks, atomic operations, or higher-level abstractions like concurrent data structures.