Loading functions from `dll` or `so`

gistfile1.txt

/// compiling:
/// g++ -std=c++0x -o example example.cpp -I./libtool/include/ -L./libtool/lib/ -lltdl
///

#include <cstdio>
#include <iostream>
#include <memory>
#include <ltdl.h>

int main()
{
    lt_dlinit();
    lt_dlhandle handle = lt_dlopen("example_dll.dll");

    if (handle == nullptr)
        return 1;

    const char* error;

    lt_dlerror();

    std::function<void(const char*)> hello = reinterpret_cast<void(__stdcall *)(const char*)>(lt_dlsym(handle, "hello@4"));
    if ((error = lt_dlerror()) != nullptr)
    {
        std::cout << "Error: " << error << std::endl;
        return 2;
    }

    hello("World");

    std::function<int(int)> Double = reinterpret_cast<int(*)(int)>(lt_dlsym(handle, "Double"));
    if ((error = lt_dlerror()) != nullptr)
    {
        std::cout << "Error: " << error << std::endl;
        return 2;
    }

    std::cout << Double(333) << std::endl;

    std::function<void(void)> CppFunc = reinterpret_cast<void(*)(void)>(lt_dlsym(handle, "_Z7CppFuncv"));
    if ((error = lt_dlerror()) != nullptr)
    {
        std::cout << "Error: " << error << std::endl;
        return 2;
    }

    CppFunc();

    std::cout << "END OF TEST" << std::endl;

    lt_dlclose(handle);
    lt_dlexit();
    return 0;
}