How do I use std::lock_guard in C++?

How do I use std::lock_guard in C++?

You can use std::lock_guard to manage mutexes automatically. It locks the mutex when created and unlocks it when destroyed.

Can you show me a simple example?

Sure! Here's a basic example:

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

std::mutex mtx;

void printThreadSafe(int id) {
    std::lock_guard<std::mutex> lock(mtx);
    std::cout << "Thread " << id << " is running." << std::endl;
}

int main() {
    std::thread t1(printThreadSafe, 1);
    std::thread t2(printThreadSafe, 2);
    t1.join();
    t2.join();
    return 0;
}

What happens if I forget to unlock the mutex?

If you forget to unlock the mutex, it can lead to deadlocks or resource contention, causing your program to hang.

Are there any alternatives to std::lock_guard?

Yes, alternatives include std::unique_lock, which offers more flexibility, and std::scoped_lock, which can lock multiple mutexes.