How do I use std::lock in multithreading?

How do I use std::lock in multithreading?

You can use std::lock to prevent deadlocks by locking multiple mutexes at once. Would you like an example?

Yes, please provide an example of using std::lock.

Sure! Here's a simple example:

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

std::mutex m1, m2;

void threadFunc1() {
    std::lock(m1, m2);
    std::lock_guard<std::mutex> lg1(m1, std::adopt_lock);
    std::lock_guard<std::mutex> lg2(m2, std::adopt_lock);
    // Critical section
}

void threadFunc2() {
    std::lock(m1, m2);
    std::lock_guard<std::mutex> lg1(m1, std::adopt_lock);
    std::lock_guard<std::mutex> lg2(m2, std::adopt_lock);
    // Critical section
}

What happens if I don't use std::lock?

If you don't use std::lock, you risk encountering deadlocks or race conditions, which can lead to unpredictable behavior.