doc/sources/c++/main.cpp


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#include "polygon.h"

#include <iostream>
#include <dlfcn.h>

int main()
{
    using std::cout;
    using std::cerr;

    // load the triangle library
    void* triangle = dlopen("./triangle.so", RTLD_LAZY);
    
    if (!triangle)
    {
        cerr << "Cannot load library: " << dlerror() << '\n';
        return 1;
    }

    // load the symbols
    create_t* create_triangle = (create_t*) dlsym(triangle, "create");
    destroy_t* destroy_triangle = (destroy_t*) dlsym(triangle, "destroy");
    
    if (!create_triangle || !destroy_triangle)
    {
        cerr << "Cannot load symbols: " << dlerror() << '\n';
        return 1;
    }

    // create an instance of the class
    polygon* poly = create_triangle();

    // use the class
    poly->set_side_length(7);
        cout << "The area is: " << poly->area() << '\n';

    // destroy the class
    destroy_triangle(poly);

    // unload the triangle library
    dlclose(triangle);
    
    return 0;
}