diff --git a/scsh/tty.scm b/scsh/tty.scm
index cf8327c..1fc2684 100644
--- a/scsh/tty.scm
+++ b/scsh/tty.scm
@@ -100,7 +100,8 @@
 
 
 (define (sleazy-call/file tty opener proc)
-  (if (string? tty) (opener tty proc)
+  (if (string? tty) 
+      (opener tty (lambda (port) (sleazy-call/fdes port proc)))
       (sleazy-call/fdes tty proc)))
 
 ;;; (tty-info [fd/port/fname])
@@ -121,7 +122,9 @@
 		      (decode-baud-rate ospeed-code) ospeed-code
 		      (char->ascii (string-ref control-chars ttychar/min))
 		      (char->ascii (string-ref control-chars ttychar/time))))
-     (sleazy-call/fdes fdport (lambda (fd) (%tty-info fd control-chars))))))
+     (sleazy-call/file fdport 
+                       call-with-input-file
+                       (lambda (fd) (%tty-info fd control-chars))))))
 
 (import-os-error-syscall %tty-info (fdes control-chars) 
   "scheme_tcgetattr")
@@ -168,8 +171,9 @@
 	(cc (tty-info:control-chars info))
 	(is (%tty-info:input-speed-code  info))
 	(os (%tty-info:output-speed-code info)))
-    (sleazy-call/fdes 
+    (sleazy-call/file
      fdport
+     call-with-input-file
      (lambda (fd)
        (%set-tty-info fd option
 		      cc
@@ -203,10 +207,12 @@
 ;;; Send a break on the serial line.
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-(define (send-tty-break fdport . maybe-duration)
-  (sleazy-call/fdes fdport
-    (lambda (fdes)
-      (%send-tty-break-fdes fdes (:optional maybe-duration 0)))))
+(define (send-tty-break . args)
+  (let-optionals args ((tty (current-output-port))
+                       (duration 0))
+    (sleazy-call/file tty call-with-output-file
+                      (lambda (fdes)
+                        (%send-tty-break-fdes fdes duration)))))
 
 (import-os-error-syscall %send-tty-break-fdes (fdes duration) 
   "sch_tcsendbreak")
@@ -214,12 +220,15 @@
 ;;; Drain the main vein.
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-(define (drain-tty fdport)
-  (cond ((integer? fdport) (%tcdrain fdport))	; File descriptor.
-	((fdport? fdport)			; Scheme port -- flush first.
-	 (force-output fdport)
-	 (sleazy-call/fdes fdport %tcdrain))
-	(else (error "Illegal argument to DRAIN-TTY" fdport))))
+(define (drain-tty . maybe-tty)
+  (let ((tty (:optional maybe-tty (current-output-port))))
+    (cond ((integer? tty) (%tcdrain tty)) ; File descriptor.
+          ((fdport? tty)                ; Scheme port -- flush first.
+           (force-output tty)
+           (sleazy-call/fdes tty %tcdrain))
+          ((string? tty)                ; file name
+           (sleazy-call/file tty call-with-output-file %tcdrain))
+          (else (error "Illegal argument to DRAIN-TTY" tty)))))
 
 (import-os-error-syscall %tcdrain (fdes) "sch_tcdrain")
 
@@ -228,13 +237,21 @@
 ;;; Note that the magic %flush-tty/foo constants must be defined before this
 ;;; file is loaded due to the flush-tty/foo definitions below.
 
-(define (make-tty-flusher flag)
-  (lambda (fdport)
-    (sleazy-call/fdes fdport (lambda (fdes) (%tcflush fdes flag)))))
+(define (make-input-tty-flusher flag)
+  (lambda maybe-tty
+    (sleazy-call/file (:optional maybe-tty (current-input-port))
+		      call-with-input-file
+		      (lambda (fdes) (%tcflush fdes flag)))))
 
-(define flush-tty/input  (make-tty-flusher %flush-tty/input))
-(define flush-tty/output (make-tty-flusher %flush-tty/output))
-(define flush-tty/both   (make-tty-flusher %flush-tty/both))
+(define (make-output-tty-flusher flag)
+  (lambda maybe-tty
+    (sleazy-call/file (:optional maybe-tty (current-output-port))
+		      call-with-output-file
+		      (lambda (fdes) (%tcflush fdes flag)))))
+
+(define flush-tty/input  (make-input-tty-flusher  %flush-tty/input))
+(define flush-tty/output (make-output-tty-flusher %flush-tty/output))
+(define flush-tty/both   (make-input-tty-flusher  %flush-tty/both))
 
 (import-os-error-syscall %tcflush (fdes flag) "sch_tcflush")
 
@@ -243,14 +260,22 @@
 ;;; Note that the magic %tcflow/foo constants must be defined before this
 ;;; file is loaded due to the definitions below.
 
-(define (make-flow-controller action)
-  (lambda (fdport)
-    (sleazy-call/fdes fdport (lambda (fdes) (%tcflow fdes action)))))
+(define (make-input-flow-controller action)
+  (lambda maybe-tty
+    (sleazy-call/file (:optional maybe-tty (current-input-port))
+		      call-with-input-file
+		      (lambda (fdes) (%tcflow fdes action)))))
 
-(define start-tty-output (make-flow-controller %tcflow/start-out))
-(define stop-tty-output  (make-flow-controller %tcflow/stop-out))
-(define start-tty-input  (make-flow-controller %tcflow/start-in))
-(define stop-tty-input   (make-flow-controller %tcflow/stop-in))
+(define (make-output-flow-controller action)
+  (lambda maybe-tty
+    (sleazy-call/file (:optional maybe-tty (current-output-port))
+		      call-with-output-file
+		      (lambda (fdes) (%tcflow fdes action)))))
+
+(define start-tty-output (make-output-flow-controller %tcflow/start-out))
+(define stop-tty-output  (make-output-flow-controller %tcflow/stop-out))
+(define start-tty-input  (make-input-flow-controller %tcflow/start-in))
+(define stop-tty-input   (make-input-flow-controller %tcflow/stop-in))
 
 (import-os-error-syscall %tcflow (fdes action) "sch_tcflow")
 
@@ -275,8 +300,8 @@
 ;;; Set/Get tty process group
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-(define (set-tty-process-group port/fd proc-group)
-  (sleazy-call/fdes port/fd
+(define (set-tty-process-group port/fd/fname proc-group)
+  (sleazy-call/file port/fd/fname call-with-input-file
     (lambda (fd)
       (%set-tty-process-group fd (if (integer? proc-group)
 				     proc-group
@@ -284,8 +309,8 @@
 
 (import-os-error-syscall %set-tty-process-group (fdes pid) "sch_tcsetpgrp")
 
-(define (tty-process-group port/fd)
-  (sleazy-call/fdes port/fd %tty-process-group))
+(define (tty-process-group port/fd/fname)
+  (sleazy-call/file port/fd/fname call-with-input-file %tty-process-group))
 
 (import-os-error-syscall %tty-process-group (fdes) "sch_tcgetpgrp")