diff --git a/gash/pipe.scm b/gash/pipe.scm
index b095622..a3564ec 100644
--- a/gash/pipe.scm
+++ b/gash/pipe.scm
@@ -82,25 +82,77 @@
            (and src (close src))))))
 
 
-(define (pipeline fg? . commands)
-  (let ((job (new-job)))
-    (if (> (length commands) 1)
-        (let loop ((src (spawn-source fg? job (car commands)))
-                   (commands (cdr commands)))
-          (if (null? (cdr commands))
-              (spawn-sink fg? job src (car commands))
-              (loop (spawn-filter fg? job src (car commands))
-                    (cdr commands))))
-        (spawn-sink fg? job #f (car commands)))
-    (if fg? (wait job))))
+(define* (spawn fg? job command #:optional (input '()) (output 0))
+  ;;(format #t "spawn: ~a ~a\n" (length input) output)
+  (let* ((ofd (iota output 1)) ;; output file descriptors 1, ...
+	 (count (length input))
+	 (start (1+ output))
+	 (ifd (cond
+	       ((= count 0) '())
+	       ((= count 1) '(0))
+	       ((#t (cons 0 (iota (1- count) start))))))
+	 (ifd (if (pair? input) (cons 0 ifd) ifd))
+	 ;;(foo (format #t "ifd: ~a\n" ifd))
+	 ;;(foo (format #t "ofd: ~a\n" ofd))
+	 (pipes (map (lambda (. _) (pipe)) ofd))
+	 (r (map car pipes))
+	 (w (map cdr pipes))
+	 (pid (primitive-fork)))
+      (cond ((= 0 pid)
+	     (setup-process fg? job)
+	     (map close r)
+	     (map move->fdes w ofd)
+	     (map move->fdes input ifd)
+             (if (procedure? command)
+		 (begin
+		   (when (pair? input)
+		     (close-port (current-input-port))
+		     (set-current-input-port (car input)))
+		   (when (pair? w)
+		     (close-port (current-output-port))
+		     (set-current-output-port (car w)))
+		   (command)
+		   (exit 0))
+		 (exec* command)))
+            (#t
+             (job-add-process fg? job pid command)
+             (map close w)
+             r))))
 
-;;(pipeline #t (list "sleep" "10"))
+(define (pipeline+ fg? open? . commands)
+  (let* ((job (new-job))
+	 (ports (if (> (length commands) 1)
+		   (let loop ((input (spawn fg? job (car commands) '() 1)) ;; spawn-source
+			      (commands (cdr commands)))
+		     (if (null? (cdr commands))
+			 (spawn fg? job (car commands) input (if open? 1 0)) ;; spawn-sink
+			 (loop (spawn fg? job (car commands) input 1) ;; spawn-filter
+			       (cdr commands))))
+		   (spawn fg? job (car commands) `((current-input-port))))))
+    (if fg? (wait job) (values job ports))))
+
+(define (pipeline fg? . commands)
+  (apply pipeline+ (cons* fg? #f commands)))
+
+;;(pipeline #f '("head" "-c128" "/dev/urandom") '("tr" "-dc" "A-Z0-9") (lambda () (display (read-string))))
+;;(pipeline #f '("head" "-c128" "/dev/urandom") '("tr" "-dc" "A-Z0-9") '("cat"))
 ;;(pipeline #f (lambda () (display 'foo)) '("grep" "o") '("tr" "o" "e"))
-(pipeline #f
-	  (lambda () (display "bin\nboot\nroot\ntoot\nusr\nvar"))
-	  ;;'("tr" "o" "e")
-	  (lambda () (display (string-map (lambda (c) (if (eq? c #\o) #\e c)) (read-string))))
-	  (lambda () (display (read-string)) (newline)))
+
+;; (pipeline #f
+;; 	  (lambda () (display "\nbin\nboot\nroot\nusr\nvar"))
+;; 	  '("tr" "u" "a")
+;; 	  (lambda () (display (string-map (lambda (c) (if (eq? c #\o) #\e c)) (read-string))))
+;; 	  '("cat")
+;; 	  (lambda () (display (read-string))))
+
+;; (receive (job ports)
+;;     (pipeline+ #f #t
+;; 	      (lambda () (display "\nbin\nboot\nroot\nusr\nvar"))
+;; 	      '("tr" "u" "a")
+;; 	      (lambda () (display (string-map (lambda (c) (if (eq? c #\o) #\e c)) (read-string))))
+;; 	      '("cat"))
+;;   (display (read-string (car ports))))
+
 
 (define (pipeline->string . commands)
   (let* ((fg? #f)
@@ -117,6 +169,18 @@
     (wait job)
     output))
 
+;; _
+;;  \
+;;   -
+;; _/
+
+;; (display (pipeline->string
+;;   (lambda () (display "\nbin\nboot\nroot\nusr\nvar"))
+;;   '("tr" "u" "a")
+;;   (lambda () (display (string-map (lambda (c) (if (eq? c #\o) #\e c)) (read-string))))
+;;   '("cat")
+;;   (lambda () (display (read-string)) (newline))))
+
 (define (substitute . commands)
   (string-trim-right
    (string-map (lambda (c)