What are shared mutexes in C++?

What are shared mutexes in C++?

Shared mutexes in C++ allow multiple threads to read shared data simultaneously while ensuring exclusive access for writing.

How do I implement a shared mutex in my code?

You can implement a shared mutex using std::shared_mutex from the <shared_mutex> header. Use lock_shared() for reading and lock() for writing.

Can you give me a code example?

Sure! Here's a simple example:

#include <iostream>
#include <shared_mutex>
#include <thread>

std::shared_mutex mtx;
int shared_data = 0;

void read_data() {
    std::shared_lock<std::shared_mutex> lock(mtx);
    std::cout << "Data: " << shared_data << std::endl;
}

void write_data(int value) {
    std::unique_lock<std::shared_mutex> lock(mtx);
    shared_data = value;
}

This code demonstrates reading and writing with a shared mutex.

What are the advantages of using shared mutexes?

The main advantage is improved performance in read-heavy scenarios, as multiple threads can read concurrently without blocking each other.