C++11 multithreading with class member function [duplicate]

Answer 1

You need to pass two things: a pointer-to-member, and the object. You cannot call a non-static member function (like Gamma) in C++ without an object. The correct syntax would be:

std::thread gamma_thread(&Beta::Gamma, // the pointer-to-member
                         my_beta,      // the object, could also be a pointer
                         5);           // the argument

You can think of my_beta here as being the first argument to Gamma(), and 5 as the second.

Answer 2

You need to name the function, then pass the object on which to call it as an explicit implicit this parameter. :)

std::thread gamma_thread(&Beta::Gamma, my_beta, 5);

This is a bit of an abstraction leak, granted.

Answer 3

You have multiple problems in your program

1. As your compile error says, you need to pass the address of the function &Beta::Gamma.
2. You need to pass the object as a parameter considering this is an implicit parameter of a member function

Modified source

#include <thread>
#include <iostream>

class Beta
{
public:
    void Gamma(int y)
    {
        while (true)
        {
            std::cout << y << std::endl;
        }
    }
};

int main()
{
    Beta my_beta;
    std::thread gamma_thread(&Beta::Gamma, my_beta, 5);
    gamma_thread.join();

    return 0;
}