UsePointers

Declare Function CallWindowProc& Lib "user32" _
Alias "CallWindowProcA" (ByVal lpPrevWndFunc&, _
ByVal hWnd&, ByVal Msg&, ByVal wParam&, _
ByVal lParam&)

Declare Sub CopyMemory Lib "kernel32" _
Alias "RtlMoveMemory" (lpvDest As Any, _
lpvSource As Any, ByVal cbCopy As Long)

Option Explicit
'____________________________________________________________


Private Function StripStringFromPointer$(ByVal lpString&, _
ByVal nStrLen&)
Dim Info$
Info = String$(nStrLen, vbNullChar)
CopyMemory ByVal StrPtr(Info), ByVal lpString, nStrLen * 2
StripStringFromPointer = Info
End Function
'____________________________________________________________


Private Function GetAddress(Addr&)
GetAddress = Addr
End Function
'____________________________________________________________


Private Function MyFunction&(ByVal lpString&, _
ByVal nStrLen&, ByVal param3&,
ByVal param4&)
Debug.Print StripStringFromPointer(lpString, nStrLen)
End Function
'____________________________________________________________


Public Sub Main()
Dim FunctAddr&, Info$
Info = "Holy Smoke"
FunctAddr = GetAddress(AddressOf MyFunction)
CallWindowProc FunctAddr, StrPtr(Info), CLng(Len(Info)), 0&, 0&
End
End Sub