C语言如何开发简单的插件

#include "polygon.h"
#include <stdlib.h>
#include <dlfcn.h>

int main()
{
    typedef CPolygon* create_t();

    void * handle = dlopen("./triangle.so", RTLD_LAZY);

    if( !handle )
    {
    std::cerr << dlerror() << std::endl;
    exit(1);
    }

    create_t * create_triangle = (create_t *)dlsym(handle, "create");

    CPolygon * pObj = create_triangle();

    if( 0 != pObj )
    {
    pObj->area();
    }

    delete pObj;

    dlclose(handle);
    return 0;
}