[Wisp-cvs] wisp/users/pisi whiptail.wisp,NONE,1.1

[<pi...@us...>]

Update of /cvsroot/wisp/wisp/users/pisi
In directory sc8-pr-cvs1:/tmp/cvs-serv18507

Added Files:
	whiptail.wisp 
Log Message:
capture-alternate for whiptail

--- NEW FILE: whiptail.wisp ---
;;; alternate pipe reader 
;;; whiptail prints selected items to stderr
;;; and requires stdout to be a tty (in case i want to see anything, what i do)
;;; solution - make an alternate pipe reader
;;; should this be incorporated to unix.wim someday/somehow ?

(use unix files syscalls semiraw-files)

(define (make-pipe-close-hook pid)
  (lambda (port read? write?)
	(if (and read? write?)
    	(begin
       (sys:close (file-descriptor port))
       ; FIXME: the fd slot should be NULLed too.
       (sys:waitpid pid 0)))))
                                    

(define (pipe-alternate-from proc (num 2))
  (let* ((pipe (sys:pipe))
         (child (sys:fork)))
    
    (if (zero? child)
      ; child
      (begin
        (sys:close (car pipe))
        (sys:dup2 (cdr pipe) num)
        (sys:close (cdr pipe))
        (dedicated proc))
      ; parent
      (begin
        (sys:close (cdr pipe))
        (my res (make-instance <old-file>)
          (init-input-file res (car pipe) (make-pipe-close-hook child))
          res)))))

(define (capture-alternate-lines proc num)
  (my p (pipe-alternate-from proc num)
    (hold (read-all-lines p)
      (close-input-port p))))

;;; test
(write (capture-alternate-lines "whiptail --noitem --separate-output --title Test --menu Select 20 20 10  tag1 item1 tag2 item2" 2))
(newline)
(write (capture-alternate-lines "whiptail --noitem --separate-output --title Test --checklist checkbox 20 40 10  tag1 on tag2 on \"long tag1\" on \"long tag2\" on" 2))
(newline)