DR>Thanks Dan Larson for your msg about 16-BIT TO 32-BIT CALLBAC, on
DR>Wednesday, 11-09-1994!

DL> Is there a proper typ
DL> 
DL> casting from 16-bit void to 32 bit void or other types? I would
DL> have a lot of work ahead of me if I had to edit all of those headers
DL> to  

DR>If you are in a 32 bit compiler, then to cast a 16bit pointer to a 32
DR>bit pointer would be:

DR>VOID*    _Seg16    p16Pointer;
DR>VOID*    p32Pointer;

DR>p32Pointer = p16Pointer;

This compiler thinks the void * parameter is 32-bit and will thunk it from 32 t

16 even though it is already actually 16 bit since the dll is passing it to the
call back routine. If I replaced the p16Pointer with the void * param, the
compiler does no thunking because it thinks the void * param is already 32-bit.


DR>It should be that simple. Since the types of both are known from their
DR>declarations, the compiler should correctly do the cast. I guess you
DR>could always be more explicit (which would also make the code more self
DR>documenting)

DR>p32Pointer = (VOID*)p16Pointer;

DR>But, technically speaking, that would be redudant. If this does not
DR>work for you, then I think maybe your compiler (which one??) is not a
DR>happy camper (or I am very confused, which is always another option.)

I am using IBM Cset++ 2.01. Maybe I am doing something wrong, but the IS my
first attempt at modifying headers from and existing 16-bit DLL. So far I have
changed all func prototypes from far pascal to _Far16 _Pascal, then all pointer

inside data structures to _Seg16 * instead of far *, as well as pointer to
pointers. 

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