Re: c-wrapper: performance problem

Hi Jens,

On 2008/04/11, at 3:52, Jens Thiele wrote:
> I stumbled across a performance problem:
> Converting some c byte array (char*) to a u8vector is really slow. It
> semms the bytes are copied byte for byte in scheme. But maybe my
> approach is just plain wrong?

You're right, the cast method has not been optimized for uvector yet.
If you want to use bulk copy, you can use memcpy as you do in C, such  
like the code below.

(define buf (make-u8vector 100))
;; ary is C byte array.
(memcpy buf ary 100)

An uvector is used in pointer context, the pointer of the uvector's  
storage is passed to C function.

--
KOGURO, Naoki <naoki <at> koguro.net>

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