diff --git a/collects/r6rs/private/readtable.ss b/collects/r6rs/private/readtable.ss
index 1615e6dab0..08c7f3fb7f 100644
--- a/collects/r6rs/private/readtable.ss
+++ b/collects/r6rs/private/readtable.ss
@@ -277,6 +277,10 @@
                                     col pos
                                     (and pos (+ 1 len)))))]
                             [(or (eq? char #\tab)
+                                 ;(eq? char #\newline)
+                                 ;(eq? char #\return)
+                                 ;(eq? char #\u85)
+                                 ;(eqv? char #\u2028)
                                  (eq? (char-general-category char) 'zs))
                              (let ([wm (regexp-match-positions #px"^(?:\t|\\p{Zs})*(?:\r\n|\r\u85|[\r\n\u85\u2028])(?:\t|\\p{Zs})*"
                                                                bytes 
@@ -285,7 +289,7 @@
                                    (cons (subbytes bytes bpos (caar m)) ; drop matched part
                                          (loop (cdar wm)))
                                    ;; This is an eof error if there's only intraline whitespace
-                                   ((if (regexp-match #px"^(?:\t|\\p{Zs})*$" bytes (+ 1 bpos))
+                                   ((if (regexp-match? #px"^(?:\t|\\p{Zs})*$" bytes (+ 1 bpos))
                                         raise-read-eof-error
                                         raise-read-error)
                                     "missing <line ending> after `\\<intraline-whitespace>'"
@@ -348,7 +352,7 @@
                                (map
                                 (lambda (s)
                                   (format "|\\p{~a}" s))
-                                '(Lu Lt Lm Lo Mn Nl No Pd Pc Po Sc Sm Sk So Co)))
+                                '(Ll Lu Lt Lm Lo Mn Nl No Pd Pc Po Sc Sm Sk So Co)))
                               1)
                              "))")))
     (define special-initial "[!$%&*/:<=>?^_~]")
@@ -444,10 +448,13 @@
                              (regexp-match #px"^(?:\\\\x[0-9a-fA-F]+;|[^\\\\\\s\\[\\]()#\";,'`])*" port))
                          '(#""))))])
     (cond
-     [(regexp-match rx:number thing)
+     [(regexp-match? #rx#"^[a-zA-Z!$%&*/:<=>?^_~][a-zA-Z0-9+!$%&*/:<=>?^_~.@-]*$" thing)
+      ;; Simple symbol:
+      (string->symbol (bytes->string/utf-8  thing))]
+     [(regexp-match? rx:number thing)
       (let ([n (string->number 
                 (bytes->string/utf-8
-                 ;; MzScheme doesn't hanel mantissa widths, so strip them out:
+                 ;; MzScheme doesn't handle mantissa widths, yet, so strip them out:
                  (regexp-replace* #rx#"[|][0-9]+"
                                   thing
                                   #"")))])
@@ -455,7 +462,7 @@
           (error 'r6rs-parser "number didn't convert: ~e" thing))
         n)]
      [(and (not num?)
-           (regexp-match rx:id thing))
+           (regexp-match? rx:id thing))
       (string->symbol
        (bytes->string/utf-8 
         (let loop ([t thing])
diff --git a/collects/r6rs/private/records-core.ss b/collects/r6rs/private/records-core.ss
index a30ae39978..369f1c9e2a 100644
--- a/collects/r6rs/private/records-core.ss
+++ b/collects/r6rs/private/records-core.ss
@@ -41,7 +41,6 @@
 	  record? record-rtd)
   (import (rnrs base (6))
           (rnrs lists (6))
-          (rnrs io simple (6)) ;; REMOVEME 
 	  (r6rs private vector-types))
   
   (define make-field-spec cons)
diff --git a/collects/rnrs/arithmetic/info.ss b/collects/rnrs/arithmetic/info.ss
new file mode 100644
index 0000000000..de01082fe1
--- /dev/null
+++ b/collects/rnrs/arithmetic/info.ss
@@ -0,0 +1 @@
+#lang setup/infotab
\ No newline at end of file
diff --git a/collects/rnrs/base-6.ss b/collects/rnrs/base-6.ss
index 97cd501a00..800c6ff7aa 100644
--- a/collects/rnrs/base-6.ss
+++ b/collects/rnrs/base-6.ss
@@ -11,7 +11,7 @@
 (provide 
 
  ;; 11.2
- (rename-out [r5rs:define define]
+ (rename-out [r6rs:define define]
              [r6rs:define-syntax define-syntax])
 
  ;; 11.4.1
@@ -128,6 +128,7 @@
  
  ;; 11.11
  char? char=? char<? char>? char<=? char>=?
+ integer->char char->integer
 
  ;; 11.12
  string?
@@ -153,8 +154,9 @@
  assertion-violation assert
 
  ;; 11.15
- (rename-out [r5rs:apply apply])
- call-with-current-continuation call/cc
+ (rename-out [r5rs:apply apply]
+             [r6rs:call/cc call-with-current-continuation]
+             [r6rs:call/cc call/cc])
  values call-with-values
  dynamic-wind
 
@@ -306,7 +308,7 @@
 
 (define-syntax-rule (assert expr)
   (unless expr
-    (assrtion-violation #f "assertion failed")))
+    (assertion-violation #f "assertion failed")))
 
 ;; ----------------------------------------
 ;; quasiquote generalization
@@ -314,6 +316,16 @@
 (define-generalized-qq r6rs:quasiquote 
   quasiquote unquote unquote-splicing)
 
+;; ----------------------------------------
+;; define
+
+(define-syntax (r6rs:define stx)
+  (syntax-case stx ()
+    [(_ id) 
+     (identifier? #'id)
+     #'(define id (void))]
+    [(_ . rest) #'(r5rs:define . rest)]))
+
 ;; ----------------------------------------
 ;; define-syntax: wrap a transformer to
 ;;  ensure that the result of an expansion is
@@ -358,3 +370,42 @@
        (procedure-arity v))
       v))
 
+;; ----------------------------------------
+
+(define detect-tail-key (gensym))
+
+(define (mk-k full-k tag)
+  (lambda args 
+    (if (continuation-prompt-available? tag)
+        (abort-current-continuation
+         tag
+         (lambda () (apply values args)))
+        (apply full-k args))))
+
+(define (r6rs:call/cc f)
+  (unless (and (procedure? f)
+               (procedure-arity-includes? f 1))
+    ;; let call/cc report the error:
+    (call/cc f))
+  ;; To support call/cc-based jumps in exception
+  ;;  handlers, we both grab a continuation and set a prompt
+  (let/cc k
+    (let ([v (make-continuation-prompt-tag 'r6rs:call/cc)]
+          [orig-key (continuation-mark-set-first #f detect-tail-key)])
+      (with-continuation-mark detect-tail-key v
+        (let ([new-key (continuation-mark-set-first #f detect-tail-key)])
+          (if (not (eq? new-key orig-key))
+              ;; Old mark surived => not tail wrt old call.
+              ;; Create an escape continuation to use for
+              ;; error escapes. Of course, we rely on the fact
+              ;; that continuation marks are not visible to EoPL
+              ;; programs.
+              (call-with-continuation-prompt
+               (lambda ()
+                 (f (mk-k k new-key)))
+               new-key)
+              ;; Old mark replaced => tail wrt old call.
+              ;; To preserve tail semantics for all but the first call
+              ;; reuse `mark' instead of creating a new escape continuation:
+              (with-continuation-mark detect-tail-key orig-key
+                (f (mk-k k orig-key)))))))))
diff --git a/collects/rnrs/io/info.ss b/collects/rnrs/io/info.ss
new file mode 100644
index 0000000000..c14a2ca411
--- /dev/null
+++ b/collects/rnrs/io/info.ss
@@ -0,0 +1 @@
+#lang setup/infotab
diff --git a/collects/rnrs/io/ports-6.ss b/collects/rnrs/io/ports-6.ss
index 30e9f897d5..61d3dedabe 100644
--- a/collects/rnrs/io/ports-6.ss
+++ b/collects/rnrs/io/ports-6.ss
@@ -1,9 +1,13 @@
 #lang scheme/base
 
+;; FIXME: newline decoding
+
 (require rnrs/enums-6
          rnrs/conditions-6
          r6rs/private/io-conds
-         scheme/port)
+         r6rs/private/readtable
+         scheme/port
+         scheme/pretty)
 
 (provide (all-from-out r6rs/private/io-conds)
          file-options
@@ -17,6 +21,7 @@
          transcoder-codec
          transcoder-eol-style
          transcoder-error-handling-mode
+         native-transcoder
          ;bytevector->string
          ;string->bytevector
          (rename-out [eof eof-object])
@@ -38,9 +43,44 @@
          open-bytevector-input-port
          open-string-input-port
          standard-input-port
-         current-input-port
+         (rename-out [r6rs:current-input-port current-input-port])
          make-custom-binary-input-port
-         make-custom-textual-input-port)
+         make-custom-textual-input-port
+         get-u8
+         lookahead-u8
+         get-bytevector-n
+         get-bytevector-n!
+         get-bytevector-some
+         get-bytevector-all
+         get-char
+         lookahead-char
+         get-string-n
+         get-string-n!
+         get-string-all
+         get-line
+         get-datum
+         output-port?
+         flush-output-port
+         output-port-buffer-mode
+         open-file-output-port
+         open-bytevector-output-port
+         call-with-bytevector-output-port
+         open-string-output-port
+         call-with-string-output-port
+         standard-output-port
+         standard-error-port
+         (rename-out [r6rs:current-output-port current-output-port]
+                     [r6rs:current-error-port current-error-port])
+         make-custom-binary-output-port
+         make-custom-textual-output-port
+         put-u8
+         put-bytevector
+         put-char
+         put-string
+         put-datum
+         open-file-input/output-port
+         make-custom-binary-input/output-port
+         make-custom-textual-input/output-port)
 
 ;; ----------------------------------------
 
@@ -53,11 +93,11 @@
 (define (buffer-mode? m)
   (enum-set-member? m (-buffer-modes none line block)))
 
-(define-enumeration eol-style (lf cr crlf nel crnel ls)
+(define-enumeration eol-style (lf cr crlf nel crnel ls none)
   -eol-styles)
 
 (define-struct codec (enc))
-(define latin-1 (make-codec "latin-1"))
+(define latin-1 (make-codec "latin1"))
 (define utf-8 (make-codec "utf-8"))
 (define utf-16 (make-codec "utf-16"))
 
@@ -87,14 +127,17 @@
                               [handling-mode 'replace])
   (unless (codec? codec)
     (raise-type-error 'make-transcoder "codec" codec))
-  (unless (enum-set-member? eol-style (-eol-styles lf cr crlf nel crnel ls))
-    (raise-type-error 'make-transcoder "'lf, 'cr, 'crlf, 'nel, 'crnel, or 'ls" eol-style))
+  (unless (enum-set-member? eol-style (-eol-styles lf cr crlf nel crnel ls none))
+    (raise-type-error 'make-transcoder "'lf, 'cr, 'crlf, 'nel, 'crnel, 'ls, or 'none" eol-style))
   (unless (enum-set-member? handling-mode (-handling-modes ignore raise replace))
     (raise-type-error 'make-transcoder "'ignore, 'raise, or 'replace" eol-style))
   (make-transcoder codec eol-style handling-mode))
 
+(define utf8-transcoder 
+  (make-transcoder utf-8 'none '?))
+
 (define (native-transcoder)
-  (make-transcoder utf-8))
+  utf8-transcoder)
 
 ;; ----------------------------------------
 
@@ -196,6 +239,11 @@
      (set! disconnected? #t)
      port)))
 
+;; For merging two kinds of ports:
+(define-struct dual-port (in out)
+  #:property prop:input-port 0
+  #:property prop:output-port 1)
+
 ;; R6RS functions that generate binary ports wrap them with `binary-...-port'
 ;; structures, so that the binary ports can be "closed" by `transcoded-port'.
 (define-struct binary-input-port (port disconnect get-pos set-pos!)
@@ -215,6 +263,7 @@
 
 (define (port-transcoder port)
   (cond
+   [(dual-port? port) (port-transcoder (dual-port-in port))]
    [(textual-input-port? port) (textual-input-port-transcoder port)]
    [(textual-output-port? port) (textual-output-port-transcoder port)]
    [(input-port? port) #f]
@@ -224,30 +273,46 @@
 (define (textual-port? v)
   (if (port? v)
       (or (textual-input-port? v)
-          (textual-output-port? v))
+          (textual-output-port? v)
+          (and (dual-port? v) 
+               (textual-port? (dual-port-in v))))
       (raise-type-error 'textual-port? "port" v)))
 
 (define (binary-port? v)
   (if (port? v)
       (not (or (textual-input-port? v)
-               (textual-output-port? v)))
+               (textual-output-port? v)
+               (and (dual-port? v) 
+                    (textual-port? (dual-port-in v)))))
       (raise-type-error 'binary-port? "port" v)))
 
 (define (wrap-binary-input-port p get-pos set-pos!)
   (let-values ([(p disconnect) (make-disconnectable-input-port p)])
     (make-binary-input-port p disconnect get-pos set-pos!)))
 
+(define (wrap-binary-output-port p get-pos set-pos!)
+  (let-values ([(p disconnect) (make-disconnectable-output-port p)])
+    (make-binary-output-port p disconnect get-pos set-pos!)))
+
+(define (wrap-binary-input/output-port p get-pos set-pos!)
+  (let-values ([(p disconnect) (make-disconnectable-input-port p)]
+               [(out-p out-disconnect) (make-disconnectable-output-port p)])
+    (make-binary-input/output-port p disconnect get-pos set-pos!
+                                   out-p out-disconnect)))
+
 (define (transcode-input p t)
   (let ([p (if (binary-input-port? p)
                ((binary-input-port-disconnect p))
                p)])
-    (reencode-input-port p 
-                         (codec-enc (transcoder-codec t))
-                         (case (transcoder-error-handling-mode t)
-                           [(raise) #f]
-                           [(ignore) #""]
-                           [(replace) (string->bytes/utf-8 "\uFFFD")])
-                         #t)))
+    (if (eq? t utf8-transcoder)
+        p
+        (reencode-input-port p 
+                             (codec-enc (transcoder-codec t))
+                             (case (transcoder-error-handling-mode t)
+                               [(raise) #f]
+                               [(ignore) #""]
+                               [(replace) (string->bytes/utf-8 "\uFFFD")])
+                             #t))))
 
 (define (transcode-output p t)
   (let ([p (cond
@@ -256,13 +321,15 @@
             [(binary-input/output-port? p)
              ((binary-input/output-port-out-disconnect p))]
             [else p])])
-    (reencode-output-port p 
-                          (codec-enc (transcoder-codec t))
-                          (case (transcoder-error-handling-mode t)
-                            [(raise) #f]
-                            [(ignore) #""]
-                            [(replace) (string->bytes/utf-8 "\uFFFD")])
-                          #t)))
+    (if (eq? t utf8-transcoder)
+        p
+        (reencode-output-port p 
+                              (codec-enc (transcoder-codec t))
+                              (case (transcoder-error-handling-mode t)
+                                [(raise) #f]
+                                [(ignore) #""]
+                                [(replace) (string->bytes/utf-8 "\uFFFD")])
+                              #t))))
 
 (define (transcoded-port p t)
   (unless (and (port? p)
@@ -272,13 +339,13 @@
     (raise-type-error 'transcoded-port "transcoder" t))
   (cond
    [(and (input-port? p) (output-port? p))
-    (make-textual-input/output-port (transcode-input p)
+    (make-textual-input/output-port (transcode-input p t)
                                     t 
-                                    (transcode-output p))]
+                                    (transcode-output p t))]
    [(input-port? p)
     (make-textual-input-port (transcode-input p t) t)]
    [(output-port? p)
-    (make-textual-input-port (transcode-output p t) t)]))
+    (make-textual-output-port (transcode-output p t) t)]))
 
 (define (port-has-port-position? p)
   (unless (port? p)
@@ -292,6 +359,8 @@
     (port-has-port-position? (textual-input-port-port p))]
    [(textual-output-port? p)
     (port-has-port-position? (textual-output-port-port p))]
+   [(dual-port? p)
+    (port-has-port-position? (dual-port-in p))]
    [else #t]))
 
 (define (port-position p)
@@ -304,6 +373,8 @@
     (port-position (textual-input-port-port p))]
    [(textual-output-port? p)
     (port-position (textual-output-port-port p))]
+   [(dual-port? p)
+    (port-position (dual-port-in p))]
    [else (file-position p)]))
 
 (define (port-has-set-port-position!? p)
@@ -318,6 +389,8 @@
     (port-has-set-port-position!? (textual-input-port-port p))]
    [(textual-output-port? p)
     (port-has-set-port-position!? (textual-output-port-port p))]
+   [(dual-port? p)
+    (port-has-set-port-position!? (dual-port-in p))]
    [else
     ;; FIXME
     (or (file-stream-port? p)
@@ -336,6 +409,8 @@
     (set-port-position! (textual-input-port-port p) pos)]
    [(textual-output-port? p)
     (set-port-position! (textual-output-port-port p) pos)]
+   [(dual-port? p)
+    (set-port-position! (dual-port-in p))]
    [else
     (file-position p pos)]))
 
@@ -393,13 +468,19 @@
 (define (open-string-input-port str)
   (unless (string? str)
     (raise-type-error 'open-bytevector-input-port "string" str))
-  (transcoded-port (open-input-string str) utf-8))
+  (let ([p (open-input-string str)])
+    (transcoded-port
+     (wrap-binary-input-port p
+                             (lambda () (file-position p)) 
+                             (lambda (pos) (file-position p pos)))
+     utf8-transcoder)))
 
 (define standard-input-port
   (let ([p (current-input-port)])
-    (wrap-binary-input-port p
-                            (lambda () (file-position p)) 
-                            (lambda (pos) (file-position p pos)))))
+    (lambda ()
+      (wrap-binary-input-port p
+                              (lambda () (file-position p)) 
+                              (lambda (pos) (file-position p pos))))))
 
 (define input-ports (make-hash-table 'weak))
 
@@ -410,7 +491,7 @@
      [(hash-table-get input-ports p #f)
       => ephemeron-value]
      [else
-      (let ([p2 (transcoded-port p utf-8)])
+      (let ([p2 (transcoded-port p utf8-transcoder)])
         (hash-table-put! input-ports p (make-ephemeron p p2))
         p2)])))
 
@@ -423,7 +504,7 @@
                     eof
                     v)))
             #f
-            close)])
+            (or close void))])
     (wrap-binary-input-port p
                             get-position
                             set-position!)))
@@ -448,6 +529,390 @@
                    n)))))
     get-position
     set-position!
-    close)))
+    (or close void))))
 
 ;; ----------------------------------------
+
+(define (get-u8 p)
+  (unless (binary-port? p)
+    (raise-type-error 'get-u8 "binary port" p))
+  (read-byte p))
+
+(define (lookahead-u8 p)
+  (unless (binary-port? p)
+    (raise-type-error 'lookahead-u8 "binary port" p))
+  (peek-byte p 0))
+
+(define (get-bytevector-n p cnt)
+  (unless (binary-port? p)
+    (raise-type-error 'get-bytevector-n "binary port" p))
+  (read-bytes cnt p))
+
+(define (get-bytevector-n! p bytes start end)
+  (unless (binary-port? p)
+    (raise-type-error 'get-bytevector-n! "binary port" p))
+  (read-bytes! bytes p start end))
+
+(define (get-bytevector-some p)
+  (unless (binary-port? p)
+    (raise-type-error 'get-bytevector-some "binary port" p))
+  (let ([bytes (make-bytes 4096)])
+    (let ([n (read-bytes-avail! bytes p)])
+      (if (eof-object? n)
+          n
+          (subbytes bytes 0 n)))))
+
+(define (get-bytevector-all p)
+  (unless (binary-port? p)
+    (raise-type-error 'get-bytevector-all "binary port" p))
+  (let ([p2 (open-output-bytes)])
+    (copy-port p p2)
+    (get-output-bytes p #t)))
+
+;; ----------------------------------------
+
+(define (get-char p)
+  (unless (textual-port? p)
+    (raise-type-error 'get-char "textual port" p))
+  (read-char p))
+
+(define (lookahead-char p)
+  (unless (textual-port? p)
+    (raise-type-error 'lookahead-char "textual port" p))
+  (peek-char p))
+
+(define (get-string-n p cnt)
+  (unless (textual-port? p)
+    (raise-type-error 'get-string-n "textual port" p))
+  (read-string cnt p))
+
+(define (get-string-n! p str start end)
+  (unless (textual-port? p)
+    (raise-type-error 'get-string-n! "textual port" p))
+  (read-string! str p start end))
+
+(define (get-string-all p)
+  (unless (textual-port? p)
+    (raise-type-error 'get-string-all "textual port" p))
+  (let ([p2 (open-output-bytes)])
+    (copy-port p p2)
+    (get-output-string p)))
+
+(define (get-line p)
+  (unless (textual-port? p)
+    (raise-type-error 'get-line "textual port" p))
+  (read-line p 'linefeed))
+
+(define (get-datum p)
+  (unless (textual-port? p)
+    (raise-type-error 'get-datum "textual port" p))
+  (let loop ([v (with-r6rs-reader-parameters (lambda () (read p)))])
+    (cond
+     [(pair? v) (mcons (loop (car v))
+                       (loop (cdr v)))]
+     [(vector? v) (list->vector
+                   (map loop (vector->list v)))]
+     [else v])))
+
+;; ----------------------------------------
+
+(define (flush-output-port p)
+  (flush-output p))
+
+(define (output-port-buffer-mode p)
+  (file-stream-buffer-mode p))
+
+(define (do-open-file-output-port who
+                                  filename 
+                                  options
+                                  buffer-mode
+                                  maybe-transcoder
+                                  open-output-file
+                                  file-position
+                                  wrap-binary-port)
+  (unless (enum-set=? (enum-set-universe options)
+                      (enum-set-universe (file-options)))
+    (raise-type-error who "file-options enum set" options))
+  (unless (enum-set-member? buffer-mode (-buffer-modes none line block))
+    (raise-type-error who "'none, 'line, or 'block" buffer-mode))
+  (when maybe-transcoder
+    (unless (transcoder? maybe-transcoder)
+      (raise-type-error who "transcoder or #f" maybe-transcoder)))
+  (let ([p (open-output-file filename
+                             #:exists (cond
+                                       [(or (enum-set=? options (file-options no-create no-fail no-truncate))
+                                            (enum-set=? options (file-options no-create no-truncate)))
+                                        'must-update]
+                                       [(enum-set=? options (file-options no-fail no-truncate))
+                                        'update]
+                                       [(enum-set-member? 'no-create) ; no-create, no-create + no-fail
+                                        'must-truncate]
+                                       [(enum-set-member? options 'no-fail) ; no-fail
+                                        'truncate]
+                                       [else ; no-truncate, <empty>
+                                        'error]))])
+    (file-stream-buffer-mode p buffer-mode)
+    (if maybe-transcoder
+        (transcoded-port p maybe-transcoder)
+        (wrap-binary-port p 
+                          (lambda () (file-position p)) 
+                          (lambda (pos) (file-position p pos))))))
+
+(define (open-file-output-port filename 
+                               [options (file-options)]
+                               [buffer-mode 'block]
+                               [maybe-transcoder #f])
+  (do-open-file-output-port 'open-file-output-port
+                            filename 
+                            options
+                            buffer-mode
+                            maybe-transcoder
+                            open-output-file
+                            file-position
+                            wrap-binary-output-port))
+
+(define (open-bytevector-output-port [maybe-transcoder #f])
+  (when maybe-transcoder
+    (unless (transcoder? maybe-transcoder)
+      (raise-type-error 'open-bytevector-output-port "transcoder or #f" maybe-transcoder)))
+  (let ([p (open-output-bytes)])
+    (values
+     (if maybe-transcoder
+         (transcoded-port p maybe-transcoder)
+         (wrap-binary-output-port p
+                                  (lambda () (file-position p)) 
+                                  (lambda (pos) (file-position p pos))))
+     (lambda () (get-output-bytes p #t)))))
+
+(define (call-with-bytevector-output-port proc [maybe-transcoder #f])
+  (let-values ([(p get) (open-bytevector-output-port maybe-transcoder)])
+    (proc p)
+    (close-output-port p)
+    (get)))
+
+(define (open-string-output-port)
+  (let ([p (open-output-string)])
+    (values
+     (transcoded-port p utf8-transcoder)
+     (lambda ()
+       (bytes->string/utf-8 (get-output-bytes p #t))))))
+
+(define (call-with-string-output-port proc)
+  (let-values ([(p get) (open-string-output-port)])
+    (proc p)
+    (close-output-port p)
+    (get)))
+
+(define standard-output-port
+  (let ([p (current-output-port)])
+    (lambda ()
+      (wrap-binary-output-port p
+                               (lambda () (file-position p)) 
+                               (lambda (pos) (file-position p pos))))))
+
+
+(define standard-error-port
+  (let ([p (current-error-port)])
+    (lambda ()
+      (wrap-binary-output-port p
+                               (lambda () (file-position p)) 
+                               (lambda (pos) (file-position p pos))))))
+
+(define output-ports (make-hash-table 'weak))
+
+(define (r6rs:current-output-port)
+  (convert-output-port (current-output-port)))
+
+(define (r6rs:current-error-port)
+  (convert-output-port (current-error-port)))
+
+(define (convert-output-port p)
+  (cond
+   [(textual-port? p) p]
+   [(hash-table-get output-ports p #f)
+    => ephemeron-value]
+   [else
+    (let ([p2 (transcoded-port p utf8-transcoder)])
+      (hash-table-put! output-ports p (make-ephemeron p p2))
+      p2)]))
+
+(define (make-custom-binary-output-port id write! get-position set-position! close)
+  (wrap-binary-output-port
+   (make-output-port
+    id
+    always-evt ;; assuming that it never blocks!
+    (lambda (bytes start end can-block/buffer? enable-break?)
+      (write! bytes start end))
+    (or close void)
+    #f
+    #f
+    #f
+    #f
+    void
+    0
+    #f)
+   get-position
+   set-position!))
+   
+(define (make-custom-textual-output-port id write! get-position set-position! close)
+  (transcoded-port
+   (wrap-binary-output-port
+    (make-output-port
+     id
+     always-evt ;; assuming that it never blocks!
+     (let-values ([(in out) (make-pipe)]
+                  [(c) #f]
+                  [(cvt-buffer) #f]
+                  [(buffer) #f])
+       (lambda (bytes start end can-block/buffer? enable-break?)
+         (let ([direct? (zero? (pipe-content-length in))])
+           (if (and direct?
+                    (bytes-utf-8-length bytes #f start end))
+               ;; No old bytes saved, and bytes to write form a complete
+               ;; UTF-8 encoding, so we can write directly:
+               (let ([s (bytes->string/utf-8 bytes #f start end)])
+                 (write! s 0 (string-length s)))
+               ;; Partial or need to use existing bytes, so use pipe
+               (begin
+                 (write-bytes bytes out start end)
+                 (unless buffer
+                   (set! c (bytes-open-converter "UTF-8-permissive" "UTF-8"))
+                   (set! buffer (make-bytes 4096))
+                   (set! cvt-buffer (make-bytes 4096)))
+                 (let loop ()
+                   (let ([n (peek-bytes-avail!* buffer 0 in)])
+                     (let ([more? ((pipe-content-length in) . > . n)])
+                       (let-values ([(amt used status) (bytes-convert c buffer 0 n cvt-buffer)])
+                         (when (positive? amt)
+                           (read-bytes! buffer in 0 amt)
+                           (let ([s (bytes->string/utf-8 buffer #f 0 amt)])
+                             (write! s 0 (string-length s))))
+                         (when (eq? status 'error)
+                           ;; Discard an erroneous byte
+                           (read-byte in))
+                         ;; Loop 
+                         (unless (and (eq? status 'complete)
+                                      (not more?))
+                           (loop)))))))))
+         (- end start)))
+     (or close void)
+     #f
+     #f
+     #f
+     #f
+     void
+     0
+     #f)
+    get-position
+    set-position!)
+   utf8-transcoder))
+
+;; ----------------------------------------
+
+(define (put-u8 port b)
+  (unless (binary-port? port)
+    (raise-type-error 'put-u8 "binary port" port))
+  (write-byte b port))
+
+(define (put-bytevector port bytes [start 0] [count (- (bytes-length bytes) start)])
+  (unless (binary-port? port)
+    (raise-type-error 'put-bytevector "binary port" port))
+  (write-bytes bytes port start (+ start count)))
+
+(define (put-char port ch)
+  (unless (textual-port? port)
+    (raise-type-error 'put-u8 "textual port" port))
+  (write-char ch port))
+
+(define (put-string port str [start 0] [count (- (bytes-length bytes) start)])
+  (unless (textual-port? port)
+    (raise-type-error 'put-string "textual port" port))
+  (write-string (substring str start (+ start count)) port))
+
+(define (put-datum port v)
+  (unless (textual-port? port)
+    (raise-type-error 'put-datum "textual port" port))
+  (parameterize ([print-mpair-curly-braces #f]
+                 [pretty-print-columns 'infinity]
+                 [pretty-print-size-hook
+                  (lambda (v write? p)
+                    (cond
+                     [(string? v) 
+                      (and (for/or ([c (in-string v)])
+                                   (not (or (char-graphic? c)
+                                            (char-blank? c))))
+                           (for/fold ([w 2])
+                               ([c (in-string v)])
+                             (cond
+                              [(eq? c #\") 2]
+                              [(eq? c #\\) 2]
+                              [(char-graphic? c) 1]
+                              [(char-blank? c) 1]
+                              [(eq? c #\newline) 2]
+                              [(eq? c #\return) 2]
+                              [else 9])))]
+                     [else #f]))]
+                 [pretty-print-print-hook
+                  (lambda (v write? p)
+                    (cond
+                     [(string? v) 
+                      (write-char #\" p)
+                      (for ([c (in-string v)])
+                        (cond
+                         [(eq? c #\") (display "\\\"" p)]
+                         [(eq? c #\\) (display "\\n" p)]
+                         [(char-graphic? c) (write-char c p)]
+                         [(char-blank? c) (write-char c p)]
+                         [(eq? c #\newline) (display "\\\\" p)]
+                         [(eq? c #\return) (display "\\r" p)]
+                         [else
+                          (display "\\x" p)
+                          (let ([s (format "00000~x" (char->integer c))])
+                            (display (substring s (- (string-length s) 6)) p)
+                            (write-char #\; p))]))
+                      (write-char #\" p)]))])
+    (pretty-print v port)))
+
+;; ----------------------------------------
+
+(define (open-file-input/output-port filename 
+                                     [options (file-options)]
+                                     [buffer-mode 'block]
+                                     [maybe-transcoder #f])
+  (do-open-file-output-port 'open-file-input/output-port
+                            filename 
+                            options
+                            buffer-mode
+                            maybe-transcoder
+                            (lambda (name #:exists mode)
+                              (let-values ([(in out) (open-input-output-file name #:exists mode)])
+                                (make-dual-port in out)))
+                            ;; Input and output buffering make `file-position' iffy.
+                            (if (eq? buffer-mode 'none)
+                                file-position
+                                #f)
+                            wrap-binary-input/output-port))
+
+(define (make-make-custom-input/output-port
+         make-custom-input-port
+         make-custom-output-port)
+  (lambda (id read! write! get-pos set-pos! close)
+    (let* ([closed-one? #f]
+           [close (and close
+                       (lambda ()
+                         (if closed-one?
+                             (close)
+                             (set! closed-one? #t))))])
+      (let ([in (make-custom-input-port id read! get-pos set-pos! close)]
+            [out (make-custom-output-port id write! get-pos set-pos! close)])
+        (make-dual-port in out)))))
+
+(define make-custom-binary-input/output-port
+  (make-make-custom-input/output-port
+   make-custom-binary-input-port
+   make-custom-binary-output-port))
+
+(define make-custom-textual-input/output-port
+  (make-make-custom-input/output-port
+   make-custom-textual-input-port
+   make-custom-textual-output-port))
diff --git a/collects/rnrs/io/simple-6.ss b/collects/rnrs/io/simple-6.ss
index 513e784b6f..e55b80678f 100644
--- a/collects/rnrs/io/simple-6.ss
+++ b/collects/rnrs/io/simple-6.ss
@@ -1,35 +1,66 @@
 #lang scheme/base
 
-(require r6rs/private/readtable)
+(require (prefix-in r6rs: rnrs/io/ports-6))
 
 (provide (rename-out [eof eof-object])
          eof-object?
-         call-with-input-file
-         call-with-output-file
+         (rename-out [r6rs:call-with-input-file call-with-input-file]
+                     [r6rs:call-with-output-file call-with-output-file])
          input-port?
          output-port?
-         current-input-port
-         current-output-port
-         current-error-port
-         with-input-from-file
-         with-output-to-file
-         open-input-file
-         open-output-file
+         (rename-out [r6rs:current-input-port current-input-port]
+                     [r6rs:current-output-port current-output-port]
+                     [r6rs:current-error-port current-error-port]
+                     [r6rs:with-input-from-file with-input-from-file]
+                     [r6rs:with-output-to-file with-output-to-file]
+                     [r6rs:open-input-file open-input-file]
+                     [r6rs:open-output-file open-output-file])
          close-input-port
          close-output-port
          read-char
-         peek-char
-         (rename-out [r6rs:read read])
+         (rename-out [r6rs:peek-char peek-char]
+                     [r6rs:read read])
          write-char
          newline
          display
-         write)
+         (rename-out [r6rs:write write]))
+
+(define (r6rs:call-with-input-file file proc)
+  (r6rs:call-with-port
+   (r6rs:open-input-file file)
+   proc))
+
+(define (r6rs:call-with-output-file file proc)
+  (r6rs:call-with-port
+   (r6rs:open-output-file file)
+   proc))
+
+(define (r6rs:with-input-from-file file proc)
+  (let ([p (r6rs:open-input-file file)])
+    (begin0
+     (parameterize ([current-input-port p])
+       (proc))
+     (close-input-port p))))
+
+(define (r6rs:with-output-to-file file proc)
+  (let ([p (r6rs:open-output-file file)])
+    (begin0
+     (parameterize ([current-output-port p])
+       (proc))
+     (close-output-port p))))
+
+(define (r6rs:open-input-file file)
+  (r6rs:transcoded-port (r6rs:open-file-input-port file) (r6rs:native-transcoder)))
+
+(define (r6rs:open-output-file file)
+  (r6rs:transcoded-port (r6rs:open-file-output-port file) (r6rs:native-transcoder)))
+
+(define (r6rs:peek-char [in (current-input-port)])
+  (peek-char in))
+
+(define (r6rs:read [in (r6rs:current-input-port)])
+  (r6rs:get-datum in))
+
+(define (r6rs:write v [out (r6rs:current-output-port)])
+  (r6rs:put-datum out v))
 
-(define (r6rs:read [in (current-input-port)])
-  (let loop ([v (with-r6rs-reader-parameters (lambda () (read in)))])
-    (cond
-     [(pair? v) (mcons (loop (car v))
-                       (loop (cdr v)))]
-     [(vector? v) (list->vector
-                   (map loop (vector->list v)))]
-     [else v])))
diff --git a/collects/rnrs/records/info.ss b/collects/rnrs/records/info.ss
new file mode 100644
index 0000000000..c14a2ca411
--- /dev/null
+++ b/collects/rnrs/records/info.ss
@@ -0,0 +1 @@
+#lang setup/infotab
diff --git a/collects/rnrs/unicode-6.ss b/collects/rnrs/unicode-6.ss
index 71a8829e2d..3027c0e1ce 100644
--- a/collects/rnrs/unicode-6.ss
+++ b/collects/rnrs/unicode-6.ss
@@ -19,7 +19,7 @@
  char-upper-case?
  char-lower-case?
  char-title-case?
- char-general-category
+ (rename-out [r6rs:char-general-category char-general-category])
  
  string-upcase
  string-downcase
@@ -35,3 +35,35 @@
  string-normalize-nfkd
  string-normalize-nfc
  string-normalize-nfkc)
+
+(define (r6rs:char-general-category ch)
+  (hash-table-get #hasheq((ll . Ll)
+                          (lu . Lu)
+                          (lt . Lt)
+                          (lm . Lm)
+                          (lo . Lo)
+                          (mn . Mn)
+                          (mc . Mc)
+                          (me . Me)
+                          (nl . Nl)
+                          (no . No)
+                          (nd . Nd)
+                          (zl . Zl)
+                          (zs . Zs)
+                          (zp . Zp)
+                          (pc . Pc)
+                          (pd . Pd)
+                          (ps . Ps)
+                          (pe . Pe)
+                          (pi . Pi)
+                          (pf . Pf)
+                          (po . Po)
+                          (sm . Sm)
+                          (sc . Sc)
+                          (sk . Sk)
+                          (so . So)
+                          (cf . Cf)
+                          (cn . Cn)
+                          (co . Co)
+                          (cc . Cc))
+                  (char-general-category ch)))
\ No newline at end of file
diff --git a/collects/scheme/private/kw-file.ss b/collects/scheme/private/kw-file.ss
index 2ba2b8be88..2596d8ffa7 100644
--- a/collects/scheme/private/kw-file.ss
+++ b/collects/scheme/private/kw-file.ss
@@ -12,10 +12,10 @@
            call-with-output-file*)
 
   (define exists-syms
-    '(error append update replace truncate truncate/replace))
+    '(error append update replace truncate must-truncate truncate/replace))
 
   (define exists-desc
-    "'error, 'append, 'update, 'replace, 'truncate, or 'truncate/replace")
+    "'error, 'append, 'update, 'replace, 'truncate, 'must-truncate, or 'truncate/replace")
 
   (define -open-input-file
     (let ([open-input-file (lambda (path #:mode [mode 'binary])
diff --git a/collects/scribblings/reference/file-ports.scrbl b/collects/scribblings/reference/file-ports.scrbl
index df8f73782e..c65a80a12d 100644
--- a/collects/scribblings/reference/file-ports.scrbl
+++ b/collects/scribblings/reference/file-ports.scrbl
@@ -64,7 +64,8 @@ A @tech{path} value that is the @tech{cleanse}d version of
 @defproc[(open-output-file [path path-string?]
                            [#:mode mode-flag (one-of/c 'binary 'text) 'binary]
                            [#:exists exists-flag (one-of/c 'error 'append 'update
-                                                           'replace 'truncate 'truncate/replace) 'error])
+                                                           'replace 'truncate 
+                                                           'must-truncate 'truncate/replace) 'error])
           output-port?]{
 
 Opens the file specified by @scheme[path] for output. The
@@ -86,16 +87,23 @@ Under Windows, @scheme['text] mode works only with regular files;
 attempting to use @scheme['text] with other kinds of files triggers an
 @scheme[exn:fail:filesystem] exception.
 
-The @scheme[exists-flag] argument specifies how to handle the case
-that the file already exists. 
+The @scheme[exists-flag] argument specifies how to handle/require
+files that already exist:
 
 @itemize{
 
- @item{@indexed-scheme['error] --- raise @scheme[exn:fail:filesystem].}
+ @item{@indexed-scheme['error] --- raise @scheme[exn:fail:filesystem]
+       if the file exists.}
 
- @item{@indexed-scheme['replace] --- remove the old file and write a new one.}
+ @item{@indexed-scheme['replace] --- remove the old file, if it
+       exists, and write a new one.}
 
- @item{@indexed-scheme['truncate] --- removed all old data.}
+ @item{@indexed-scheme['truncate] --- remove all old data, if the file
+       exists.}
+
+ @item{@indexed-scheme['must-truncate] --- remove all old data in an
+       existing file; if the file does not exist, the
+       @exnraise[exn:fail:filesystem].}
 
  @item{@indexed-scheme['truncate/replace] --- try @scheme['truncate];
        if it fails (perhaps due to file permissions), try
@@ -105,9 +113,10 @@ that the file already exists.
        truncating it; if the file does not exist, the
        @exnraise[exn:fail:filesystem].}
 
- @item{@indexed-scheme['append] --- append to the end of the file
-       under @|AllUnix|; under Windows, @scheme['append] is equivalent
-       to @scheme['update], except that the file position is
+ @item{@indexed-scheme['append] --- append to the end of the file,
+       whether it already exists or not; under Windows,
+       @scheme['append] is equivalent to @scheme['update], except that
+       the file is not required to exist, and the file position is
        immediately set to the end of the file after opening it.}
 
 }
diff --git a/src/mzscheme/src/port.c b/src/mzscheme/src/port.c
index e6e6ede043..554e6b0561 100644
--- a/src/mzscheme/src/port.c
+++ b/src/mzscheme/src/port.c
@@ -75,9 +75,6 @@ static int mzerrno = 0;
 # endif
 extern int osk_not_console; /* set by cmd-line flag */
 #endif
-#ifdef MAC_FILE_SYSTEM
-# include <Carbon.h>
-#endif
 #include <math.h> /* for fmod , used by default_sleep */
 #include "schfd.h"
 
@@ -189,13 +186,6 @@ typedef struct Scheme_Subprocess {
 #endif
 
 
-/******************** Mac Classic input ********************/
-
-#ifdef MAC_FILE_SYSTEM
-# define MZ_FDS
-# define MAC_FILE_HANDLES
-#endif
-
 /******************** file-descriptor I/O ********************/
 
 /* Windows/Mac I/O is piggy-backed on Unix file-descriptor I/O.  Making
@@ -235,7 +225,7 @@ typedef struct Scheme_FD {
 # include <fcntl.h>
 #endif
 
-#if defined(WINDOWS_FILE_HANDLES) || defined(MAC_FILE_HANDLES)
+#if defined(WINDOWS_FILE_HANDLES)
 # define FILENAME_EXN_E "%E"
 #else
 # define FILENAME_EXN_E "%e"
@@ -355,6 +345,7 @@ static void force_close_input_port(Scheme_Object *port);
 static Scheme_Object *text_symbol, *binary_symbol;
 static Scheme_Object *append_symbol, *error_symbol, *update_symbol;
 static Scheme_Object *replace_symbol, *truncate_symbol, *truncate_replace_symbol;
+static Scheme_Object *must_truncate_symbol;
 
 Scheme_Object *scheme_none_symbol, *scheme_line_symbol, *scheme_block_symbol;
 
@@ -386,6 +377,7 @@ scheme_init_port (Scheme_Env *env)
   REGISTER_SO(truncate_symbol);
   REGISTER_SO(truncate_replace_symbol);
   REGISTER_SO(update_symbol);
+  REGISTER_SO(must_truncate_symbol);
 
   text_symbol = scheme_intern_symbol("text");
   binary_symbol = scheme_intern_symbol("binary");
@@ -395,6 +387,7 @@ scheme_init_port (Scheme_Env *env)
   truncate_symbol = scheme_intern_symbol("truncate");
   truncate_replace_symbol = scheme_intern_symbol("truncate/replace");
   update_symbol = scheme_intern_symbol("update");
+  must_truncate_symbol = scheme_intern_symbol("must-truncate");
 
   REGISTER_SO(scheme_none_symbol);
   REGISTER_SO(scheme_line_symbol);
@@ -3649,25 +3642,6 @@ scheme_do_open_input_file(char *name, int offset, int argc, Scheme_Object *argv[
     return NULL;
   }
 
-#  ifdef MAC_FILE_SYSTEM
-  {
-    FSSpec spec;
-    SInt16 refnum;
-
-    if (scheme_mac_path_to_spec(filename, &spec)) {
-      errno = FSpOpenDF(&spec, fsRdWrShPerm, &refnum);
-      if (errno == noErr)
-	result = make_fd_input_port(refnum, scheme_make_path(filename), 1, mode[1] == 't', NULL, internal);
-      else {
-	filename_exn(name, "could not open file", filename, errno);
-	return NULL;
-      }
-    } else {
-      filename_exn(name, "could not open file", filename, 0);
-      return NULL;
-    }
-  }
-#  else
   regfile = scheme_is_regular_file(filename);
 
   fp = fopen(filename, mode);
@@ -3678,7 +3652,6 @@ scheme_do_open_input_file(char *name, int offset, int argc, Scheme_Object *argv[
   scheme_file_open_count++;
 
   result = scheme_make_named_file_input_port(fp, scheme_make_path(filename));
-#  endif
 # endif
 #endif
 
@@ -3703,7 +3676,7 @@ scheme_do_open_output_file(char *name, int offset, int argc, Scheme_Object *argv
 # endif
 #endif
   int e_set = 0, m_set = 0, i;
-  int existsok = 0;
+  int existsok = 0, must_exist = 0;
   char *filename;
   char mode[4];
   int typepos;
@@ -3731,6 +3704,10 @@ scheme_do_open_output_file(char *name, int offset, int argc, Scheme_Object *argv
     } else if (SAME_OBJ(argv[i], truncate_symbol)) {
       existsok = -1;
       e_set++;
+    } else if (SAME_OBJ(argv[i], must_truncate_symbol)) {
+      existsok = -1;
+      must_exist = 1;
+      e_set++;
     } else if (SAME_OBJ(argv[i], truncate_replace_symbol)) {
       existsok = -2;
       e_set++;
@@ -3795,7 +3772,7 @@ scheme_do_open_output_file(char *name, int offset, int argc, Scheme_Object *argv
 #ifdef USE_FD_PORTS
   /* Note: assuming there's no difference between text and binary mode */
 
-  flags = (and_read ? O_RDWR : O_WRONLY) | O_CREAT;
+  flags = (and_read ? O_RDWR : O_WRONLY) | (must_exist ? 0 : O_CREAT);
 
   if (mode[0] == 'a')
     flags |= O_APPEND;
@@ -3861,12 +3838,17 @@ scheme_do_open_output_file(char *name, int offset, int argc, Scheme_Object *argv
 # ifdef WINDOWS_FILE_HANDLES
   if (!existsok)
     hmode = CREATE_NEW;
-  else if (existsok < 0)
-    hmode = OPEN_ALWAYS;
-  else if (existsok  == 1)
+  else if (existsok < 0) {
+    if (must_exist)
+      hmode = TRUNCATE_EXISTING;
+    else
+      hmode = OPEN_ALWAYS;
+  } else if (existsok  == 1) {
+    /* assert: !must_exist */
     hmode = CREATE_ALWAYS;
-  else if (existsok  == 2)
-    hmode = OPEN_ALWAYS;
+  } else if (existsok == 2) {
+    hmode = OPEN_EXISTING;
+  }
 
   fd = CreateFileW(WIDE_PATH(filename),
 		   GENERIC_WRITE | (and_read ? GENERIC_READ : 0),
@@ -3948,50 +3930,6 @@ scheme_do_open_output_file(char *name, int offset, int argc, Scheme_Object *argv
   }
 
 
-#  ifdef MAC_FILE_SYSTEM
-  {
-    FSSpec spec;
-    SInt16 refnum;
-    int creating = 0;
-
-    if (scheme_mac_path_to_spec(filename, &spec)) {
-      if (existsok == 1) {
-	/* In case it's there: */
-	FSpDelete(&spec);
-      }
-
-      errno = FSpCreate(&spec, 'MrEd', 'TEXT', smSystemScript);
-      if (errno == dupFNErr) {
-	if (!existsok) {
-	  scheme_raise_exn(MZEXN_FAIL_FILESYSTEM_EXISTS,
-			   "%s: file \"%q\" exists", name, filename);
-	  return NULL;
-	}
-      } else
-	creating = 1;
-      errno = FSpOpenDF(&spec, fsRdWrShPerm, &refnum);
-      if ((errno == noErr) && (existsok < 0)) {
-	/* truncate or truncate/replace */
-	SetEOF(refnum, 0);
-      }
-
-      if (errno == noErr) {
-	if (creating)
-	  scheme_file_create_hook(filename);
-
-	scheme_file_open_count++;
-	return make_fd_output_port(refnum, scheme_make_path(filename), 1, mode[1] == 't', and_read);
-      } else {
-	filename_exn(name, "could not open file", filename, errno);
-	return NULL;
-      }
-    } else {
-      filename_exn(name, "could not open file", filename, 0);
-      return NULL;
-    }
-  }
-#  else
-
   if (and_read) {
     scheme_raise_exn(MZEXN_FAIL_UNSUPPORTED,
 		     "%s: not supported on this platform",
@@ -4041,7 +3979,6 @@ scheme_do_open_output_file(char *name, int offset, int argc, Scheme_Object *argv
   scheme_file_open_count++;
 
   return scheme_make_file_output_port(fp);
-#  endif
 # endif
 #endif
 }
@@ -4659,9 +4596,6 @@ fd_byte_ready (Scheme_Input_Port *port)
 
     return 0;
 #else
-# ifdef MAC_FILE_HANDLES
-    return 1;
-# else
     int r;
     DECL_FDSET(readfds, 1);
     DECL_FDSET(exnfds, 1);
@@ -4697,7 +4631,6 @@ fd_byte_ready (Scheme_Input_Port *port)
 # endif
 
     return r;
-# endif
 #endif
   }
 }
@@ -4865,17 +4798,6 @@ static long fd_get_string_slow(Scheme_Input_Port *port,
       }
     }
 #else
-# ifdef MAC_FILE_HANDLES
-    {
-      SInt32 cnt = target_size;
-
-      errno = FSRead(fip->fd, &cnt, target + target_offset);
-      if (!cnt && (errno != eofErr))
-        bc = -1;
-      else
-        bc = cnt;
-    }
-# else
     if (fip->regfile) {
       do {
         bc = read(fip->fd, target + target_offset, target_size);
@@ -4898,7 +4820,6 @@ static long fd_get_string_slow(Scheme_Input_Port *port,
         bc = 0;
       }
     }
-# endif
 #endif
 
     if (!none_avail) {
@@ -5010,16 +4931,10 @@ fd_close_input(Scheme_Input_Port *port)
   }
 #else
   if (!fip->refcount || !*fip->refcount) {
-# ifdef MAC_FILE_HANDLES
-    FSClose(fip->fd);
-# else
-    {
-      int cr;
-      do {
-	cr = close(fip->fd);
-      } while ((cr == -1) && (errno == EINTR));
-    }
-# endif
+    int cr;
+    do {
+      cr = close(fip->fd);
+    } while ((cr == -1) && (errno == EINTR));
   }
 #endif
 
@@ -5033,11 +4948,8 @@ fd_need_wakeup(Scheme_Input_Port *port, void *fds)
 
 #ifdef WINDOWS_FILE_HANDLES
 #else
-# ifdef MAC_FILE_HANDLES
-# else
   void *fds2;
   int n;
-# endif
 #endif
 
   fip = (Scheme_FD *)port->port_data;
@@ -5065,13 +4977,10 @@ fd_need_wakeup(Scheme_Input_Port *port, void *fds)
     scheme_add_fd_handle((void *)fip->fd, fds, 0);
   }
 #else
-# ifdef MAC_FILE_HANDLES
-# else
   n = fip->fd;
   MZ_FD_SET(n, (fd_set *)fds);
   fds2 = MZ_GET_FDSET(fds, 2);
   MZ_FD_SET(n, (fd_set *)fds2);
-# endif
 #endif
 }
 
@@ -5676,9 +5585,6 @@ fd_write_ready (Scheme_Object *port)
   } else
     return 1; /* non-blocking output, such as a console, or haven't written yet */
 #else
-# ifdef MAC_FILE_HANDLES
-  return 1;
-# else
   {
     DECL_FDSET(writefds, 1);
     DECL_FDSET(exnfds, 1);
@@ -5699,7 +5605,6 @@ fd_write_ready (Scheme_Object *port)
 
     return sr;
   }
-# endif
 #endif
 }
 
@@ -5712,11 +5617,8 @@ fd_write_need_wakeup(Scheme_Object *port, void *fds)
 
 #ifdef WINDOWS_FILE_HANDLES
 #else
-# ifdef MAC_FILE_HANDLES
-# else
   void *fds2;
   int n;
-# endif
 #endif
 
   op = scheme_output_port_record(port);
@@ -5728,14 +5630,11 @@ fd_write_need_wakeup(Scheme_Object *port, void *fds)
   else
     scheme_add_fd_nosleep(fds);
 #else
-# ifdef MAC_FILE_HANDLES
-# else
   n = fop->fd;
   fds2 = MZ_GET_FDSET(fds, 1);
   MZ_FD_SET(n, (fd_set *)fds2);
   fds2 = MZ_GET_FDSET(fds, 2);
   MZ_FD_SET(n, (fd_set *)fds2);
-# endif
 #endif
 }
 
@@ -6088,17 +5987,6 @@ static long flush_fd(Scheme_Output_Port *op,
 	}
       }
 #else
-# ifdef MAC_FILE_HANDLES
-      {
-	SInt32 put = buflen - offset;
-	errsaved = FSWrite(fop->fd, &put, bufstr + offset);
-	if (errsaved != noErr)
-	  len = -1;
-	else
-	  len = put;
-	full_write_buffer = 0;
-      }
-# else
       int flags;
 
       flags = fcntl(fop->fd, F_GETFL, 0);
@@ -6112,7 +6000,6 @@ static long flush_fd(Scheme_Output_Port *op,
       fcntl(fop->fd, F_SETFL, flags);
 
       full_write_buffer = (errsaved == EAGAIN);
-# endif
 #endif
 
       if (len < 0) {
@@ -6272,16 +6159,10 @@ fd_close_output(Scheme_Output_Port *port)
   }
 #else
   if (!fop->refcount || !*fop->refcount) {
-# ifdef MAC_FILE_HANDLES
-    FSClose(fop->fd);
-# else
-    {
-      int cr;
-      do {
-	cr = close(fop->fd);
-      } while ((cr == -1) && (errno == EINTR));
-    }
-# endif
+    int cr;
+    do {
+      cr = close(fop->fd);
+    } while ((cr == -1) && (errno == EINTR));
   }
 #endif
 
diff --git a/src/mzscheme/src/portfun.c b/src/mzscheme/src/portfun.c
index c45435eaa4..22ba493b46 100644
--- a/src/mzscheme/src/portfun.c
+++ b/src/mzscheme/src/portfun.c
@@ -4075,7 +4075,7 @@ display_write(char *name,
     Scheme_Object *a[2];
 
     a[0] = argv[0];
-    a[1] = port;
+    a[1] = (Scheme_Object *)port;
 
     h = op->print_handler;
 
diff --git a/src/mzscheme/src/print.c b/src/mzscheme/src/print.c
index 4f6fbc8b1d..cf91c486fe 100644
--- a/src/mzscheme/src/print.c
+++ b/src/mzscheme/src/print.c
@@ -841,7 +841,7 @@ print_to_port(char *name, Scheme_Object *obj, Scheme_Object *port, int notdispla
   char *str;
   long len;
   
-  op = (Scheme_Output_Port *)port;
+  op = scheme_output_port_record(port);
   if (op->closed)
     scheme_raise_exn(MZEXN_FAIL, "%s: output port is closed", name);