Alex,
If you want the DLL to work with a chunk of memory that VFP knows about VFP has to send an address of the buffer to the DLL. Your stack address that the DLL tried to send to VFP was outside the memory VFP can access thus protection violation.
declare integer TheDLL in mydll string @ cBuffer
cBuffer = space(30)
? TheDLL( &cBuffer )
int TheDLL( char * VFPBuffer )
{
strcpy( VFPBuffer, "Hi VFP" );
return strlen( VFPBuffer );
}
On my site is another article under Q&A, General that talks about structs and VFP.
>>If you need something, lemme know.
>
>I know the offer wasn't for me, but still... :-)
>
>Let me sound ridiculous for a little bit ok? You're all alowed to laugh a bit but you have to pay me a beer.
>
>Thanks to all of you, who gave me very nice pointers (so to speak <g>), I can finally make VFP chew the DLL. But that's for simple values...
>Let the fun begin:
>
>The C code:
>
>typedef struct tst_stru
>{
> int iVal;
>} TST_STRU;
>
>TST_STRU getstru()
>{
> TST_STRU local_struct;
> local_struct.iVal = 154;
> return (local_struct);
>}
>>
>And the Fox code:
>
>Declare String getstru In DLLTest
>
>? getstru
>
>
>Now... This (why am I not surprised?
) crashes VFP. Why?
