Re: Struck with CopyMemory API

> Sounds like you either forgot a ByVal or used one where it shouldn't be. If you're
> copying data where you shouldn't be, that's a pretty classic *KaBoom!* scenario. (On
> NT systems, any address <&10000 is definitely off-limits, btw.)

You may want to try validating your read/write pointers:

'***
Private Declare Function IsBadReadPtr Lib "Kernel32.dll" (ByRef lp As Any, ByVal ucb As Long) As Long
Private Declare Function IsBadWritePtr Lib "Kernel32.dll" (ByRef lp As Any, ByVal ucb As Long) As Long

....

Private Function IsValidReadPtr(ByVal inPtr As Long, Optional ByVal inSize As Long = 1) As Boolean
IsValidReadPtr = IsBadReadPtr(ByVal inPtr, inSize) = 0
End Function

Private Function IsValidWritePtr(ByVal inPtr As Long, Optional ByVal inSize As Long = 1) As Boolean
IsValidWritePtr = IsBadWritePtr(ByVal inPtr, inSize) = 0
End Function
'***

Use them something like this:

'***
Dim MyVar As Long

Debug.Print IsValidReadPtr(VarPtr(MyVar)) ' True
Debug.Print IsValidWritePtr(VarPtr(MyVar)) ' True
Debug.Print IsValidReadPtr(0) ' False
Debug.Print IsValidWritePtr(0) ' False
'***

Hope this helps,

Mike


- Microsoft Visual Basic MVP -
E-Mail: EDais@xxxxxxxx
WWW: Http://EDais.mvps.org/


.

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