Re: #define SOMETHING some_value

[Matt Wette]

> On Jun 10, 2017, at 1:31 AM, Catonano <address@hidden> wrote:
> 
> The Freexl documentation states that I should call freexl_get_info like this
> 
> freexl_get_info(&handler, FREEXL_BIFF_SHEET_COUNT, &outcome);
> 
> Now, FREEXL_BIFF_SHEET_COUNT is defined in the header file like this
> 
> /** Information query for BIFF sheet count */
> #define FREEXL_BIFF_SHEET_COUNT        32010
> 
> But at the REPL, when I call my procedure like this
> 
> scheme@(freexl common)> (freexl-open "resources/Lavoro_P.xls")
> $1 = #<pointer 0x1227f50>
> scheme@(freexl common)> (freexl-get-info $1 32010)
> 
> I get
> 
> ERROR: Throw to key `get-info-error' with args `(error-code -3)'.
> 
> That is, an exception is being raised, as you can see in this excerpt of my
> code
> 
> (define freexl-get-info
>  (let* ((ptr     (freexl-func "freexl_get_info"))
>         (proc    (pointer->procedure int ptr (list '* unsigned-int '*))))
>    (lambda (handle-ptr what)
>      (let* ((outcome-ptr (bytevector->pointer (make-bytevector (sizeof
> unsigned-int))))
>         (result (proc handle-ptr what outcome-ptr)))
>    (if (not (= result 0))
>        (throw 'get-info-error 'error-code result) <-- THIS IS THE
> EXCEPTION BEING RAISED
>        outcome-ptr)
>    ))))
> 
> How do I deal with these #define'd things ?
> 
> I tried with both unsigned-int and uint16
> 
> Thanks in advance

Yea.  I may have steered you wrong before. (I didn’t look back.)  The argument 
signature might need to be (list ‘* unsigned-short ‘*) rather than your current 
one with unsigned-int.