Re: set handle to NULL

Kevin,

At 10:57 PM -0600 8/13/02, Kevin Rosenberg wrote:
>On Mon, Aug 12, 2002 at 11:11:29PM -0400, John DeSoi wrote:
>>      isc_db_handle   newdb = NULL;          /* database handle */
>>      isc_tr_handle   trans = NULL;          /* transaction handle */
>[...]
>  >     if (isc_dsql_execute_immediate(status, &newdb, &trans, 0, create_db, 1,
>>                                     NULL))
>
>I think you need to make a void-pointer object, then set the value of
>that object to 0, then pass the address of the objet. This way,
>isc_dsql_execute_immediate can store some value in the storage that
>you allocated for the object.


So

(setf newdb (uffi:allocate-foreign-object :pointer-void))
(setf (uffi:deref-pointer newdb) 0)


Then call isc_dsql_execute_immediate with (uffi:pointer-address 
newdb) ? I also tried passing another pointer:

(fli:make-pointer :address (uffi:pointer-address newdb))

I always get a processor fault error.


I have the db-handle parameter typed as (* isc-db-handle) and

(uffi:def-foreign-type isc-db-handle :pointer-void)



I get the "bad db handle" error if I create the handle like this:

(setf newdb (uffi:allocate-foreign-object (:pointer isc-db-handle))


So I'm assuming the part I'm missing is getting it set to NULL. What 
is the correct way to do this? Sorry if I'm being dense. All the C 
pointer stuff makes me really like Lisp :)

Thanks,


John DeSoi, Ph.D.