How do you call pthread_create() on a non-static member function from outside a class

Question

I would like to be able to create a thread of a non-static member function of a class from outside the class without having to call a static helper function. Is this possible? I know that non-static member functions usually have a 'this' parameter added implicitly but how would one be able to explicitly add 'this' to the function call within the pthread_create() call? This needs to be done using pthread. An example of what I would like to achieve is shown in the code below

class A
{
    void* nonStaticFunction()
    {
        cout<<"Hi"<<endl;
        return NULL;
    }
}

typedef void* (*THREADFUNCPTR)(void*);

int main()
{
    A* a = new A();
    pthread_t pthread;
    pthread_create(&pthread,NULL,(THREADFUNCPTR) &A::nonStaticFunction,a);
    return 0;
}