VB -> DLL Sending Function Pointer [Bad Calling Convention]

[gameschild]

Getting a bad calling convention when calling a DLL from C++ with a long as parameter, yet it works fine for other functions!

C++ code for the DLL

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extern "C" MY_API void SetCallBackStatusNotify(FARPROC theCallBack);
extern "C" MY_API void SetCallBackStatusNotifyA(long theCallBack);


Module code in VB

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Declare Function SetCallBackStatusNotifyA Lib "C:\x\y.dll" (ByVal func As Long)

Public Function callBackStatus(stype As Integer, sid As Integer)
    MsgBox "woot"
End Function

Public Function FARPROC(x As Long) As Long
    FARPROC = x
End Function


Calling Code in Visual Basic form

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Dim l As Long

l = FARPROC(AddressOf callBackStatus)
Call SetCallBackStatusNotifyA(l)


Any help would be great!

[Adron]

Try:

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Declare Sub SetCallBackStatusNotifyA Lib "C:\x\y.dll" (ByVal func As Long)

[gameschild]

the problem was the __stdcall && __cdecl problem so it only worked when running from compiled code not the IDE. however, now, when it calls back to a function callbackStatusNotify(ByVal x as long,ByVal y as long) there is a memory access problem.

tried changing byval/byref but no joy.

[dxoigmn]

the problem was the __stdcall && __cdecl problem so it only worked when running from compiled code not the IDE. however, now, when it calls back to a function callbackStatusNotify(ByVal x as long,ByVal y as long) there is a memory access problem.

tried changing byval/byref but no joy.

Show us callbackStatusNotify() code?

[Adron]

the problem was the __stdcall && __cdecl problem so it only worked when running from compiled code not the IDE. however, now, when it calls back to a function callbackStatusNotify(ByVal x as long,ByVal y as long) there is a memory access problem.

tried changing byval/byref but no joy.

I have never heard of __stdcall vs __cdecl having a solution in compiling the code. I do know that it typically fails if you tell it that the function will return a Variant instead of telling it it will return nothing at all.