How do I use mutexes in C++?

How do I use mutexes in C++?

Mutexes in C++ are used to protect shared data from being accessed by multiple threads simultaneously. You can use the std::mutex class from the <mutex> header.

Can you show me a simple example?

Sure! Here's a basic example:

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

std::mutex mtx;
int shared_data = 0;

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

int main() {
    std::thread t1(increment);
    std::thread t2(increment);
    t1.join();
    t2.join();
    std::cout << "Shared data: " << shared_data << std::endl;
    return 0;
}

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 mutexes?

Yes, alternatives include using std::lock_guard for automatic locking and unlocking, or using higher-level abstractions like std::shared_mutex for shared access.