لود کردن کتابخانه ها در gcc و برنامه نویسی کراس پلتفرم

#ifndef USE_PRECOMPILED_HEADERS
#ifdef WIN32
#include <direct.h>
#include <windows.h>
#else
#include <sys/types.h>
#include <dlfcn.h>
#endif
#include <iostream>
#endif

    using namespace std;

#ifdef WIN32
    HINSTANCE lib_handle;
#else
    void *lib_handle;
#endif

    // Where retType is the pointer to a return type of the function
    // This return type can be int, float, double, etc or a struct or class.

    typedef retType* func_t;  

    // load the library -------------------------------------------------
#ifdef WIN32
    string nameOfLibToLoad("C:\opt\lib\libctest.dll");
    lib_handle = LoadLibrary(TEXT(nameOfLibToLoad.c_str()));
    if (!lib_handle) {
        cerr << "Cannot load library: " << TEXT(nameOfDllToLoad.c_str()) << endl;
    }
#else
    string nameOfLibToLoad("/opt/lib/libctest.so");
    lib_handle = dlopen(nameOfLibToLoad.c_str(), RTLD_LAZY);
    if (!lib_handle) {
        cerr << "Cannot load library: " << dlerror() << endl;
    }
#endif

...
...
...

    // load the symbols -------------------------------------------------
#ifdef WIN32
    func_t* fn_handle = (func_t*) GetProcAddress(lib_handle, "superfunctionx");
    if (!fn_handle) {
        cerr << "Cannot load symbol superfunctionx: " << GetLastError() << endl;
    }
#else
    // reset errors
    dlerror();

    // load the symbols (handle to function "superfunctionx")
    func_t* fn_handle= (func_t*) dlsym(lib_handle, "superfunctionx");
    const char* dlsym_error = dlerror();
    if (dlsym_error) {
        cerr << "Cannot load symbol superfunctionx: " << dlsym_error << endl;
    }
#endif

...
...
...

    // unload the library -----------------------------------------------

#ifdef WIN32
    FreeLibrary(lib_handle);
#else
    dlclose(lib_handle);
#endif