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C to VB 5 porting

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I'm having trouble converting a 3rd party example program from C to VB (5 Pro), they don't support VB :+(

C code
unsigned char *GlobalBlock = (unsigned char *)new unsigned char[5000];

Where GlobalBlock is used in the initialisation function
SAFEInitGlobal(GlobalBlock);

and the function prototype is
extern "C" short __declspec(dllexport) WINAPI SAFEInitGlobal(unsigned char*);

My C is very rusty so any help will be much appreciated.

Well Have a good winter holiday one and all.

MATT

ASKER CERTIFIED SOLUTION

prozak

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muffinthedog

mbaker123,
should be able to call it like the following but by the name of the function, it seems it's just allocating global memory. Do you have the body of the function?

Declare Function SAFEInitGlobal Lib "Whatever" (lpChar As Any) As Integer

Dim bte(5000) As Byte
Dim ret As Long
ret = SAFEInitGlobal(bte(0))

prozak

Actually I pretty sure that muffinthedog's comment will not work. VB uses OLE SAFEARRAYs to store data in an array. Unlike C the memory is managed by windows and when you pass an array to a C function, you're not passing the block of elements. Your passing a pointer to a SAFEARRAY structure. I can pretty much guarantee that it will crash if you do it that way (passing an array of bytes).

muffinthedog

Worked for me... passed a pointer to an array of bytes, kinda like a pointer to an array of characters...

prozak

I stand corrected :)

mbaker123

ASKER

Cheers I'll give that a try
Festive stuff
Matt

muffinthedog

mbaker123...
just noticed I wrote Dim ret as long.....
should be Integer... sorry, just playing...