diff --git a/scsh/scsh-interfaces.scm b/scsh/scsh-interfaces.scm
index 7e199b1..a208b96 100644
--- a/scsh/scsh-interfaces.scm
+++ b/scsh/scsh-interfaces.scm
@@ -597,8 +597,8 @@
 	  run/sexps*
 	  run/strings*
 
-	  char-filter
-	  string-filter))
+	  make-char-port-filter
+	  make-string-port-filter))
 
 
 (define-interface scsh-version-interface
diff --git a/scsh/scsh.scm b/scsh/scsh.scm
index 3e74c45..37815dc 100644
--- a/scsh/scsh.scm
+++ b/scsh/scsh.scm
@@ -887,7 +887,7 @@
 ;; Loop until EOF reading characters or strings and writing (FILTER char)
 ;; or (FILTER string). Useful as an arg to FORK or FORK/PIPE.
 
-(define (char-filter filter)
+(define (make-char-port-filter filter)
   (lambda ()
     (let lp ()
       (let ((c (read-char)))
@@ -895,7 +895,7 @@
 	    (begin (write-char (filter c))
 		   (lp)))))))
 
-(define (string-filter filter . maybe-buflen)
+(define (make-string-port-filter filter . maybe-buflen)
   (let* ((buflen (:optional maybe-buflen 1024))
 	 (buf (make-string buflen)))
     (lambda ()