diff --git a/scheme/ikarus.io.ss b/scheme/ikarus.io.ss
index 20fa47a..2971628 100644
--- a/scheme/ikarus.io.ss
+++ b/scheme/ikarus.io.ss
@@ -2610,7 +2610,10 @@
       (let ([rv (foreign-call "ikrt_readdir" 
                    (directory-stream-pointer x))])
         (cond
-          [(eqv? rv 0) #f]
+          [(fixnum? rv)
+           (close-directory-stream x #f)
+           (io-error who (directory-stream-filename x) rv)]
+          [(not rv) #f]
           [else (utf8->string rv)])))
 
     (define close-directory-stream
diff --git a/scheme/last-revision b/scheme/last-revision
index 1351198..4f5ed40 100644
--- a/scheme/last-revision
+++ b/scheme/last-revision
@@ -1 +1 @@
-1762
+1763
diff --git a/src/ikarus-io.c b/src/ikarus-io.c
index 2f8b0dc..d8277d5 100644
--- a/src/ikarus-io.c
+++ b/src/ikarus-io.c
@@ -391,11 +391,12 @@ ikrt_opendir(ikptr dirname, ikpcb* pcb){
 ikptr
 ikrt_readdir(ikptr ptr, ikpcb* pcb){
   DIR* d = (DIR*) ref(ptr, off_pointer_data);
+  errno = 0;
   struct dirent* ent = readdir(d);
   if (ent == NULL){
-    return 0;
+    return (errno ? ik_errno_to_code() : false_object);
   }
-  int len = ent->d_namlen;
+  int len = strlen(ent->d_name);
   ikptr bv = ik_safe_alloc(pcb, align(disp_bytevector_data+len+1))
              + bytevector_tag;
   ref(bv, -bytevector_tag) = fix(len);