[plt-scheme] FFI and MD5

Woodhouse, Gregory J. skrev:
> Well, that's a Unicode string, and if it is encoded as UTF-8, then it's not surprising that the likes of 1d are encoded a single bytes, but higher valued codepoints are encoded as multiple bytes. Just a guess.  

For a second, I thought, you had the solution, but ...

If I use list->bytes instead of integer->string, then I get:

   (define (md5 d)
     (let ([md (MD5 d #f)])
       (let loop ([i 0] [cs '()])
         (if (= i 16)
             (list->bytes (reverse cs))
             (loop (+ i 1) (cons (ptr-ref md _byte i) cs))))))

I get:

   > (md5 #"")
   #"\324\35\214\331\217\0\262\4\351\200\t\230\354\370B~"

and I was expecting:

    #"d41d8cd98f00b204e9800998ecf8427e"

-- 
Jens Axel Søgaard