#!/usr/local/bin/scsh -s
!#

;;; Add the numbers of kb of free and used disk space for all the volumes
;;; reported by df(1)

(define (df-free+used)
  (let ((df-read (field-reader)))
    (exec-epf 
     (| (df)
        (begin 
          (read-line) ; skip first line of df
          (awk (df-read) (line fields)
               ((used-kb 0) (free-kb 0))
               (#t (values (+ used-kb (string->number (nth fields 2)))
                             (+ free-kb (string->number (nth fields 3)))))
               (after
                (values `('used-mb ,(/ used-kb 1024.0))
                        `('free-mb ,(/ free-kb 1024.0))))))))))

(receive 
 (used-list free-list) 
 (df-free+used)
 (format #t "Es sind ~A MB belegt und noch ~A MB frei~%"
         (cadr used-list)
         (cadr free-list)))