Threads usage problem with classes

[misfit382]

Hi,
I have encountered a problem using threads with the help of classes. I have been using sample codes so far as well as browsing the forum, but unfortunately I cannot find an answer to this problem.
Following the guide about threads I got something like this

Unfortunately I don't understand why a function of void type not belonging to a class passes in the compilation without any problem, but in the other direction it doesn't.

I apologize for bothering you with probably simple problems and for my poor English

Thanks

[Josh]

Is port_scanner::test2 a static function?

You might need to add & in front of test2, i.e. &test2 or maybe &port_scanner::test2.

Maybe try to create a simple example and post the code so we can test it.

[misfit382]

11 minutes ago, Josh said:

Is port_scanner::test2 a static function?

Maybe try to create a simple example and post the code so we can test it.

Sure, here u go with main.cpp file - should be enough to show the problem. I can't afford to use static functions in this case.

#include "UltraEngine.h"

using namespace UltraEngine;

class testclass {
private:
    void test2(const int start, const int size);
    void test();
};

void testclass::test2(const int start, const int size)
{
    int i;
    for (int num = start; num <= start + size; num++) {
        //something here
    }
}

void testclass::test() {
    int thread_count = 40;
    int range = 65535;
    vector<shared_ptr<Thread> > threads(thread_count);
    for (int n = 0; n < thread_count; ++n)
    {
        threads[n] = CreateThread(bind((test2), range / thread_count * n, range / thread_count), true);
    }
    for (int n = 0; n < 40; ++n)
    {
        threads[n]->Wait();
    }
}
int main(int argc, const char* argv[])
{
  
    return 0;
}

 

[Josh]

Just make declare the function like this in the header and it will work:

static void test2(const int start, const int size);

If it is a method for a specific object then you will need to use a lambda function, which would be something like this:

auto o = make_shared<testclass>();
int start = range / thread_count * n;
int size = range / thread_count;
threads[n] = CreateThread([o, start, size]() {o->test2(start, size); }, true);

[misfit382]

Thanks, lambda solves everything