diff --git a/scheme/ikarus.io.ss b/scheme/ikarus.io.ss
index 8fcfcbc..20a842f 100644
--- a/scheme/ikarus.io.ss
+++ b/scheme/ikarus.io.ss
@@ -1863,15 +1863,15 @@
                [else
                 ($bytevector-set! s i x)
                 (let f ([p p] [s s] [start i] [i 1] [c c])
-                  (let ([x (get-u8 p)])
-                    (cond
-                      [(eof-object? x) i]
-                      [else
-                       ($bytevector-set! s ($fx+ start i) x)
-                       (let ([i ($fxadd1 i)])
-                         (if ($fx= i c)
-                             i
-                             (f p s start i c)))])))])))]
+                  (cond
+                    [($fx= i c) i]
+                    [else
+                     (let ([x (get-u8 p)])
+                       (cond
+                         [(eof-object? x) i]
+                         [else
+                          ($bytevector-set! s ($fx+ start i) x)
+                          (f p s start ($fx+ i 1) c)]))]))])))]
         [($fx= c 0) 0]
         [else (die 'get-bytevector-n! "count is negative" c)])))
 
diff --git a/scheme/last-revision b/scheme/last-revision
index 41cca09..2e5f524 100644
--- a/scheme/last-revision
+++ b/scheme/last-revision
@@ -1 +1 @@
-1815
+1817
diff --git a/scheme/tests/io.ss b/scheme/tests/io.ss
index d022eea..364aa9c 100755
--- a/scheme/tests/io.ss
+++ b/scheme/tests/io.ss
@@ -706,8 +706,21 @@
            (put-bytevector p '#vu8(0)))
          (assert (equal? (e) (make-bytevector (* 86 2) 0))))))
 
+  (define (test-get-bytevector-n)
+    (let ((p (open-bytevector-input-port '#vu8(1 2 3 4 5 6 7 8 9)))
+          (buf (make-bytevector 10 #xff)))
+      (let ([buf1 
+             (begin
+               (printf "going to read 5 bytes: ~s\n" (get-bytevector-n! p buf 0 5))
+               (printf "result: ~s\n" buf)
+               (bytevector-copy buf))])
+          (printf "going to read 1 byte: ~s\n" (get-bytevector-n! p buf 5 1))
+          (printf "result: ~s\n" buf)
+          (unless (bytevector=? buf '#vu8(1 2 3 4 5 6 #xff #xff #xff #xff))
+           (error 'test "the data is not correct" buf1 buf)))))
 
   (define (run-tests)
+    (test-get-bytevector-n) 
     (test-custom-binary-input-ports)
     (test-custom-binary-output-ports)
     (run-exhaustive-tests)