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GetProcAddress fails

Yours3lf (91)
Hi,

I'm developing a non-mfc application that uses a dll file (which I made too).
when I try to load the dll file LoadLibrary is successful (does not return NULL), however GetProcAddress fails (returns NULL).
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if(hook_setup_func == NULL)

{

  HINSTANCE hook_instance;



  if(((hook_instance = LoadLibrary(_T("hook.dll"))) != NULL) && 

     ((hook_uninstall_func = (hook_uninstall_type)GetProcAddress(hook_instance,"hook_uninstall")) != NULL) && 

     ((hook_install_func = (hook_install_type)GetProcAddress(hook_instance,"hook_install")) != NULL))

  {

    if((hook_setup_func = (hook_setup_type)GetProcAddress(hook_instance,"hook_setup")) == NULL)

    {

      throw std::runtime_error("Couldn't install the hook, case 1");

    }

  }

  else

  {

//this throws error
    throw std::runtime_error("Couldn't install the hook, case 2");

  }

}


here's the corressponding declaration:
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typedef void (*hook_setup_type)(HWND, BOOL);
typedef BOOL (*hook_install_type)();
typedef void (*hook_uninstall_type)();
hook_setup_type hook_setup_func;
hook_install_type hook_install_func;
hook_uninstall_type hook_uninstall_func;


and in the dll file:
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__declspec(dllexport) void hook_setup(HWND hwnd, BOOL use_the_hook);

__declspec(dllexport) BOOL hook_install();

__declspec(dllexport) void hook_uninstall();


EDIT:
error code is 127

any ideas why it fails?

Best regards,
Yours3!f
Last edited on
anonymous23323124 (1383)
Have you put the DLL lines inside
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extern "C" {

}


Otherwise, the symbol names are "scrambled" by the compiler (they have a load of numbers and symbols stuck on depending on return type, etc). Thus they are not called what you expect without the extern "C" bit.
Yours3lf (91)
thank you Xander314, extern "C" solved the problem :)
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