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Subject: Re: How to import C pointers to structures?
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On 19-May-14 16:44, Adam Beneschan wrote:
>> You generally *can't*  do a real/meaningful import w/o knowing the
>> layout.
>
> I'm not sure that's quite true ... there are lots of situations
> where you simply want to "pass through" a pointer, e.g. in
> callback situations, where a function sets up a callback and says
> "when you do the callback, please pass this pointer to it"; and
> whoever registers the callback will take the pointer, store it
> somewhere, and use it when it's needed, without ever trying to
> look at what it points to.

While those are /common/ cases, I would be hesitant to call them 
/general/ cases.

> Unfortunately, I don't see the equivalent of "void *" anywhere in
> Interfaces.C, which is what the sort of thing you'd want.  You
> could probably use Interfaces.C.Strings.chars_ptr (the equivalent
> of "char *").

Instantiate Interfaces.C.Pointers on a null-record or, perhaps, 
System.Address?