Question

I have a question regarding Shared Objects (or DLLs). I am working on a plugin loader for my game engine. I need one question answered before starting to do that, though.

If I load the data using an external function can I unload my shared object?

Here is a little code snippet:

//The Plugin:
class PythonScriptingPlugin : public Plugin {
    void * system;
public:
    PythonScriptingPlugin() {
        system = new PythonScriptingSystem;     
    }

    void * get() { return system; } //derived

};

extern "C" {

    Plugin * libLoadPlugin() {
        return new PythonScriptingPlugin;

    }

}

//main app:
void * loadPlugin() {

    void * handle = dlopen(Base::fs()->file("plugins", "libPythonScriptingPlugin.so"), RTLD_LAZY | RTLD_GLOBAL);
    typedef (void*)(*loader)();
    loader * libLoadPlugin = dlsym(handle, "libLoadPlugin");

    void * data = libLoadPlugin()->get();
    dlclose(handle);
    return data;

}

Will data get dereferenced when I call dclose?

Answer 1

No, allocated memory remains, but you will not be able to call any function from that plugin/dll. That makes your object useless.