I am trying to call a functor in std thread and trying to find the data member value after thread complete. But it is not showing expected output, here I think I am missing something, can anyone figure out what is that. The code sample is as below.
#include <iostream>
#include <thread>
using namespace std;
class A
{
int value;
public:
A() { value=0;}
void operator () (int a, int b)
{
value = a+b;
cout << "func called\n";
}
void showValue() { cout << value << "\n"; }
};
int main()
{
A threadfunc;
thread t1(threadfunc, 4, 5);
t1.join();
//threadfunc(4,5);
threadfunc.showValue();
//cout<<"Hello World";
return 0;
}
The output of above code is
func called
0
expected output
func called
9
