diff --git a/bin/ikarus b/bin/ikarus
index 0d7cd41..9cbe757 100755
Binary files a/bin/ikarus and b/bin/ikarus differ
diff --git a/bin/ikarus-runtime.c b/bin/ikarus-runtime.c
index 216d410..1bdeda7 100644
--- a/bin/ikarus-runtime.c
+++ b/bin/ikarus-runtime.c
@@ -480,6 +480,7 @@ ikp ik_uuid(ikp str){
 }
 
 
+#if 0
 ikp ik_read(ikp fdptr, ikp bufptr, ikp lenptr){
   int fd = unfix(fdptr);
   int len = unfix(lenptr);
@@ -491,7 +492,7 @@ ikp ik_read(ikp fdptr, ikp bufptr, ikp lenptr){
   }
   return fix(bytes);
 }  
-
+#endif
 
 ikp ik_write(ikp fdptr, ikp idx, ikp str){
   fprintf(stderr, "IK_WRITE\n");
@@ -782,8 +783,8 @@ ikrt_close_file(ikp fd, ikpcb* pcb){
   }
 }
 
-ikp
-ikrt_read(ikp fd, ikp buff, ikpcb* pcb){
+static ikp
+ikrt_read_to_string(ikp fd, ikp buff, ikpcb* pcb){
   int bytes =
     read(unfix(fd), string_data(buff), unfix(ref(buff, off_string_length)));
   ikp fbytes = fix(bytes);
@@ -795,6 +796,30 @@ ikrt_read(ikp fd, ikp buff, ikpcb* pcb){
   }
 }
 
+static ikp
+ikrt_read_to_bytevector(ikp fd, ikp buff, ikpcb* pcb){
+  int bytes =
+    read(unfix(fd), buff+off_bytevector_data, unfix(ref(buff, off_bytevector_length)));
+  ikp fbytes = fix(bytes);
+  if (bytes == unfix(fbytes)){
+    return fbytes;
+  } else {
+    fprintf(stderr, "ERR: ikrt_read: too big\n");
+    exit(-1);
+  }
+}
+
+ikp ikrt_read(ikp fd, ikp buff, ikpcb* pcb){
+  if(tagof(buff) == string_tag){
+    return ikrt_read_to_string(fd,buff,pcb);
+  } else {
+    return ikrt_read_to_bytevector(fd,buff,pcb);
+  }
+}
+
+
+
+
 #if 0
   if(bytes == -1){
     fprintf(stderr, "ERR=%s (%d)\n", strerror(errno), errno);
diff --git a/src/ikarus.boot b/src/ikarus.boot
index c418edb..9720221 100644
Binary files a/src/ikarus.boot and b/src/ikarus.boot differ
diff --git a/src/ikarus.collect.ss b/src/ikarus.collect.ss
index 54e19d3..bf8ffe9 100644
--- a/src/ikarus.collect.ss
+++ b/src/ikarus.collect.ss
@@ -3,7 +3,7 @@
   (export do-overflow do-overflow-words do-vararg-overflow collect
           do-stack-overflow)
   (import 
-    (ikarus) 
+    (except (ikarus) collect)
     (ikarus system $fx))
 
 (define do-overflow
diff --git a/src/ikarus.io-ports.ss b/src/ikarus.io-ports.ss
index 824ef55..ad29203 100644
--- a/src/ikarus.io-ports.ss
+++ b/src/ikarus.io-ports.ss
@@ -52,7 +52,7 @@
   ;;;
   (define $make-input-port
     (lambda (handler buffer)
-      ($make-port/input handler buffer 0 ($string-length buffer) #f 0 0)))
+      ($make-port/input handler buffer 0 (string-length buffer) #f 0 0)))
   ;;;
   (define make-input-port
     (lambda (handler buffer)
@@ -64,7 +64,7 @@
   ;;;
   (define $make-output-port
     (lambda (handler buffer)
-      ($make-port/output handler #f 0 0 buffer 0 ($string-length buffer))))
+      ($make-port/output handler #f 0 0 buffer 0 (string-length buffer))))
   ;;;
   (define make-output-port
     (lambda (handler buffer)
@@ -77,8 +77,8 @@
   (define $make-input/output-port
     (lambda (handler input-buffer output-buffer)
        ($make-port/both handler
-                  input-buffer 0 ($string-length input-buffer)
-                  output-buffer 0 ($string-length output-buffer))))
+                  input-buffer 0 (string-length input-buffer)
+                  output-buffer 0 (string-length output-buffer))))
   ;;;
   (define make-input/output-port
     (lambda (handler input-buffer output-buffer)
@@ -151,7 +151,7 @@
       (if (input-port? p)
           (if (fixnum? i)
               (if ($fx>= i 0)
-                  (if ($fx<= i ($string-length ($port-input-buffer p)))
+                  (if ($fx<= i (string-length ($port-input-buffer p)))
                       (begin
                         ($set-port-input-index! p 0)
                         ($set-port-input-size! p i))
@@ -177,7 +177,7 @@
       (if (output-port? p)
           (if (fixnum? i)
               (if ($fx>= i 0)
-                  (if ($fx<= i ($string-length ($port-output-buffer p)))
+                  (if ($fx<= i (string-length ($port-output-buffer p)))
                       (begin
                         ($set-port-output-index! p 0)
                         ($set-port-output-size! p i))
diff --git a/src/ikarus.io-primitives.unsafe.ss b/src/ikarus.io-primitives.unsafe.ss
index b395847..fcd81c9 100644
--- a/src/ikarus.io-primitives.unsafe.ss
+++ b/src/ikarus.io-primitives.unsafe.ss
@@ -14,7 +14,7 @@
       (let ([idx (port-output-index p)])
         (if ($fx< idx ($port-output-size p))
             (begin
-              ($string-set! ($port-output-buffer p) idx c)
+              (string-set! ($port-output-buffer p) idx c)
               ($set-port-output-index! p ($fxadd1 idx)))
             (($port-handler p) 'write-char c p)))))
 
@@ -24,7 +24,7 @@
         (if ($fx< idx ($port-input-size p))
             (begin
               ($set-port-input-index! p ($fxadd1 idx))
-              ($string-ref ($port-input-buffer p) idx))
+              (string-ref ($port-input-buffer p) idx))
             (begin
               (($port-handler p) 'read-char p))))))
 
@@ -32,7 +32,7 @@
     (lambda (p)
       (let ([idx ($port-input-index p)])
         (if ($fx< idx ($port-input-size p))
-            ($string-ref ($port-input-buffer p) idx)
+            (string-ref ($port-input-buffer p) idx)
             (($port-handler p) 'peek-char p)))))
 
   (define $unread-char
@@ -42,7 +42,7 @@
                  ($fx< idx ($port-input-size p)))
             (begin
               ($set-port-input-index! p idx)
-              ($string-set! ($port-input-buffer p) idx c))
+              (string-set! ($port-input-buffer p) idx c))
             (($port-handler p) 'unread-char c p)))))
 
   (define $reset-input-port!
diff --git a/src/ikarus.io.input-files.ss b/src/ikarus.io.input-files.ss
index 69bf2ca..e59fbf4 100644
--- a/src/ikarus.io.input-files.ss
+++ b/src/ikarus.io.input-files.ss
@@ -57,7 +57,7 @@
                (if ($fx< idx ($port-input-size p))
                    (begin
                      ($set-port-input-index! p ($fxadd1 idx))
-                     ($string-ref ($port-input-buffer p) idx))
+                     (string-ref ($port-input-buffer p) idx))
                    (if open?
                        (let ([bytes
                               (foreign-call "ikrt_read" 
@@ -78,7 +78,7 @@
                (error 'peek-char "~s is not an input port" p))
              (let ([idx ($port-input-index p)])
                (if ($fx< idx ($port-input-size p))
-                   ($string-ref ($port-input-buffer p) idx)
+                   (string-ref ($port-input-buffer p) idx)
                    (if open?
                        (let ([bytes
                               (foreign-call "ikrt_read" fd
@@ -101,7 +101,7 @@
                         ($fx< idx ($port-input-size p)))
                    (begin
                      ($set-port-input-index! p idx)
-                     ($string-set! ($port-input-buffer p) idx c))
+                     (string-set! ($port-input-buffer p) idx c))
                    (if open?
                        (error 'unread-char "port ~s is closed" p)
                        (error 'unread-char "too many unread-chars"))))]
diff --git a/src/ikarus.io.input-strings.ss b/src/ikarus.io.input-strings.ss
index 4e9bf76..df9fe5e 100644
--- a/src/ikarus.io.input-strings.ss
+++ b/src/ikarus.io.input-strings.ss
@@ -41,7 +41,7 @@
                (if ($fx< idx ($port-input-size p))
                    (begin
                      ($set-port-input-index! p ($fxadd1 idx))
-                     ($string-ref ($port-input-buffer p) idx))
+                     (string-ref ($port-input-buffer p) idx))
                    (if open?
                        (eof-object)
                        (error 'read-char "port ~s is closed" p))))]
@@ -50,7 +50,7 @@
                (error 'peek-char "~s is not an input port" p))
              (let ([idx ($port-input-index p)])
                (if ($fx< idx ($port-input-size p))
-                   ($string-ref ($port-input-buffer p) idx)
+                   (string-ref ($port-input-buffer p) idx)
                    (if open?
                        (eof-object)
                        (error 'peek-char "port ~s is closed" p))))]
@@ -62,7 +62,7 @@
                         ($fx< idx ($port-input-size p)))
                    (begin
                      ($set-port-input-index! p idx)
-                     ($string-set! ($port-input-buffer p) idx c))
+                     (string-set! ($port-input-buffer p) idx c))
                    (if open?
                        (error 'unread-char "port ~s is closed" p)
                        (error 'unread-char "too many unread-chars"))))]
diff --git a/src/ikarus.io.output-files.ss b/src/ikarus.io.output-files.ss
index 4ebad95..1e43c47 100644
--- a/src/ikarus.io.output-files.ss
+++ b/src/ikarus.io.output-files.ss
@@ -70,7 +70,7 @@
                      (let ([idx ($port-output-index p)])
                         (if ($fx< idx ($port-output-size p))
                             (begin
-                              ($string-set! ($port-output-buffer p) idx c)
+                              (string-set! ($port-output-buffer p) idx c)
                               ($set-port-output-index! p ($fxadd1 idx)))
                             (if open?
                               (begin
diff --git a/src/ikarus.io.output-strings.ss b/src/ikarus.io.output-strings.ss
index d68bee3..16b1fa8 100644
--- a/src/ikarus.io.output-strings.ss
+++ b/src/ikarus.io.output-strings.ss
@@ -38,18 +38,18 @@
   (define concat 
     (lambda (str i ls)
       (let ([n (sum i ls)])
-        (let ([outstr ($make-string n)])
+        (let ([outstr (make-string n)])
           (let f ([n (copy outstr str i n)] [ls ls])
             (if (null? ls)
                 outstr
                 (let ([a ($car ls)])
-                  (f (copy outstr a ($string-length a) n) ($cdr ls)))))))))
+                  (f (copy outstr a (string-length a) n) ($cdr ls)))))))))
 
   (define sum 
     (lambda (ac ls)
       (cond
         [(null? ls) ac]
-        [else (sum ($fx+ ac ($string-length ($car ls))) ($cdr ls))])))
+        [else (sum ($fx+ ac (string-length ($car ls))) ($cdr ls))])))
   
   (define copy
     (lambda (dst src n end)
@@ -59,7 +59,7 @@
           [($fx= si 0) di]
           [else
            (let ([di ($fxsub1 di)] [si ($fxsub1 si)])
-             ($string-set! dst di ($string-ref src si))
+             (string-set! dst di (string-ref src si))
              (f di si))]))))
   
   (define make-output-string-handler
@@ -75,7 +75,7 @@
                      (let ([idx ($port-output-index p)])
                         (if ($fx< idx ($port-output-size p))
                             (begin
-                              ($string-set! ($port-output-buffer p) idx c)
+                              (string-set! ($port-output-buffer p) idx c)
                               ($set-port-output-index! p ($fxadd1 idx)))
                             (if open?
                               (begin
@@ -83,7 +83,7 @@
                                   (cons (string-copy (port-output-buffer p))
                                         buffer-list))
                                 ($set-port-output-size! p 
-                                  ($string-length ($port-output-buffer p)))
+                                  (string-length ($port-output-buffer p)))
                                 ($write-char c p))
                               (error 'write-char "port ~s is closed" p))))
                      (error 'write-char "~s is not an output-port" p))