#include <cstdlib>
#include <iostream>
#include <windows.h>
#include "AtUsbHid.h"

using namespace std;

int main(int argc, char *argv[])
{
    HINSTANCE hLib = NULL;
    hLib =LoadLibrary(AT_USB_HID_DLL);
    if(hLib == NULL){
        cout << "boing\n";
    }
    loadFuncPointers(hLib);

    system("PAUSE");
    return EXIT_SUCCESS;
}

und das ist die AtUsbHid.h:

#ifndef _ATUSBHID_H_
#define _ATUSBHID_H_

// Error codes.
#define ERROR_USB_DEVICE_NOT_FOUND          0xE0000001
#define ERROR_USB_DEVICE_NO_CAPABILITIES    0xE0000002

// name of the DLL to be loaded
#define AT_USB_HID_DLL "AtUsbHid"

// Implement the DLL export/import mechanism and allow a C-written program
// to use our DLL.
#ifdef ATUSBHID_EXPORTS
#define ATUSBHID_API extern "C" __declspec(dllexport)
#else
#define ATUSBHID_API extern "C" __declspec(dllimport)
#endif

// This macro function calls the C runtime's _beginthreadex function.
// The C runtime library doesn't want to have any reliance on Windows' data
// types such as HANDLE. This means that a Windows programmer needs to cast
// values when using _beginthreadex. Since this is terribly inconvenient,
// this macro has been created to perform the casting.
typedef unsigned(__stdcall *PTHREAD_START)(void *);

#define chBEGINTHREADEX(psa, cbStack, pfnStartAddr, \
   pvParam, fdwCreate, pdwThreadId)                 \
      ((HANDLE)_beginthreadex(                      \
         (void *)        (psa),                     \
         (unsigned)      (cbStack),                 \
         (PTHREAD_START) (pfnStartAddr),            \
         (void *)        (pvParam),                 \
         (unsigned)      (fdwCreate),               \
(unsigned *)(pdwThreadId)))

// Allow applications not built with Microsoft Visual C++ to link with our DLL.
#define STDCALL __stdcall

// These macros make calling our DLL functions through pointers easier.
#define DECLARE_FUNCTION_POINTER(FUNC)  PF_##FUNC lp##FUNC=NULL;
#define LOAD_FUNCTION_POINTER(DLL,FUNC) lp##FUNC = (PF_##FUNC)GetProcAddress(DLL, #FUNC);
#define ADDR_CHECK(FUNC) if (lp##FUNC == NULL) {fprintf(stderr,"%s\n", "Error: Cannot get address of function."); return FALSE;}
#define DYNCALL(FUNC) lp##FUNC

///////////////////////////////////////////////////////////////////////////////
typedef BOOLEAN (STDCALL *PF_findHidDevice)(const UINT VendorID, const UINT ProductID);
typedef void    (STDCALL *PF_closeDevice)(void);
typedef BOOLEAN (STDCALL *PF_writeData)(UCHAR* buffer);
typedef BOOLEAN (STDCALL *PF_readData)(UCHAR* buffer);
typedef int     (STDCALL *PF_hidRegisterDeviceNotification)(HWND hWnd);
typedef void    (STDCALL *PF_hidUnregisterDeviceNotification)(HWND hWnd);
typedef int     (STDCALL *PF_isMyDeviceNotification)(DWORD dwData);
typedef BOOLEAN (STDCALL *PF_startBootLoader)(void);
typedef BOOLEAN (STDCALL *PF_setFeature)(UCHAR type,UCHAR direction, unsigned int length);
///////////////////////////////////////////////////////////////////////////////

// Exported functions prototypes.

///////////////////////////////////////////////////////////////////////////////
ATUSBHID_API BOOLEAN STDCALL findHidDevice(const UINT VendorID, const UINT ProductID);

//  Closes the USB device and all handles before exiting the application.
ATUSBHID_API void    STDCALL closeDevice(void);

ATUSBHID_API BOOLEAN STDCALL writeData(UCHAR* buf);

ATUSBHID_API BOOLEAN STDCALL readData(UCHAR* buffer);

ATUSBHID_API int     STDCALL hidRegisterDeviceNotification(HWND hWnd);

ATUSBHID_API void    STDCALL hidUnregisterDeviceNotification(HWND hWnd);

ATUSBHID_API int     STDCALL isMyDeviceNotification(DWORD dwData);

ATUSBHID_API BOOLEAN STDCALL setFeature(UCHAR type,UCHAR direction, unsigned int length);

///////////////////////////////////////////////////////////////////////////////

#ifndef ATUSBHID_EXPORTS

DECLARE_FUNCTION_POINTER(findHidDevice);
DECLARE_FUNCTION_POINTER(closeDevice);
DECLARE_FUNCTION_POINTER(writeData);
DECLARE_FUNCTION_POINTER(readData);
DECLARE_FUNCTION_POINTER(hidRegisterDeviceNotification);
DECLARE_FUNCTION_POINTER(hidUnregisterDeviceNotification);
DECLARE_FUNCTION_POINTER(isMyDeviceNotification);
DECLARE_FUNCTION_POINTER(setFeature);

// this function call all function available in the DLL *
static bool loadFuncPointers(HINSTANCE hLib)
{
    LOAD_FUNCTION_POINTER(hLib, findHidDevice);
    ADDR_CHECK(findHidDevice);

	LOAD_FUNCTION_POINTER(hLib, closeDevice);
    ADDR_CHECK(closeDevice);

	LOAD_FUNCTION_POINTER(hLib, writeData);
    ADDR_CHECK(writeData);

	LOAD_FUNCTION_POINTER(hLib, readData);
    ADDR_CHECK(readData);

	LOAD_FUNCTION_POINTER(hLib, hidRegisterDeviceNotification);
	ADDR_CHECK(hidRegisterDeviceNotification);

	LOAD_FUNCTION_POINTER(hLib, hidUnregisterDeviceNotification);
	ADDR_CHECK(hidUnregisterDeviceNotification);

	LOAD_FUNCTION_POINTER(hLib, isMyDeviceNotification);
	ADDR_CHECK(isMyDeviceNotification);

	LOAD_FUNCTION_POINTER(hLib, setFeature);
	ADDR_CHECK(setFeature);

    return true;
}

#endif

#endif  // _ATUSBHID_H_

Compiliert wird ohne Problem. beim laufen gibt es dann folgende Ausgabe:
boing
Error: Cannot get address of function.
Kann mir da jemand weiterhelfen? Programmier erst wieder seit kurzen C++ und das bissche Wissen,was ich mal hatte, ist wieder total eingerostet. *nerv*

bei

// name of the DLL to be loaded
#define AT_USB_HID_DLL "AtUsbHid.dll" // <- .dll nicht vergessen

Und du solltest sicherstellen, dass die Datei auch tatsächlich so heißt.

gruß
Martin

Im Zweifelsfall bitte auch folgende Hinweise beachten:
C/C++ Forum :: FAQ - Sonstiges :: Wohin mit meiner Frage?

Dieses Posting wurde automatisch erzeugt.

Bezüglich der defines: Das is schon ziemlich schlimm, aber du solltes mal die Atmel Firmware für den Micocontroller sehen. Da wird hin und her definiert...GRAUSAM. Was die sich dabei wohl gedacht haben.

Bezüglich des Verschiebens; habs eigentlich ganz bewusst nicht in das WinApi-Forum gesetz, weil es ja keine Windows-Library ist, aber gut, wenn die Moderatoren meinen, es passt hier besser, ist mir das auch recht.

Besten Dank nochmal!

Also "C++" ist mit Sicherheit das falscheste Forum überhaupt

http://www.henkessoft.de/C++/WinAPI/WinAPI Kapitel 1 bis 6/api6.htm