Megatest

	     (begin
	       (set! best     (cons disk-num dirpath))
	       (set! bestsize freespc)))))
     (map car disks))
    (if (and best (> bestsize minsize))
	best
	#f))) ;; #f means no disk candidate found

;; convert a spec string to a list of vectors #( rx  action rx-string )
(define (common:spec-string->list-of-specs spec-string actions)
  (let ((spec-strings  (string-split-fields "\\s*;\\s*" spec-string #:infix))
	(actions-regex (regexp (conc "^(.*)\\s+(" (string-intersperse (map conc actions) "|") ")"))))
    (filter
     (lambda (x) x)
     (map (lambda (s)
	    (let ((m (string-match actions-regex s)))
	      (if m
		  (vector (regexp (cadr m))(string->symbol (caddr m))(cadr m))
		  (begin
		    (debug:print 0 *default-log-port* "WARNING: Unrecognised rule \"" s "\" in clean-up specification.")
		    #f))))
	  spec-strings))))
  
;; given a list of specs rx . rule and a file return the first matching rule
;; 
(define (common:file-find-rule fname rules) ;; rule is vector #( rx action rx-string)
  (let loop ((rule   (car rules))
	     (tail   (cdr rules)))
    (let ((rx (vector-ref rule 0))
	  (rn (vector-ref rule 1))) ;; rule name
      (if (string-match rx fname)
	  rule ;; return the whole rule so regex can be printed etc.
	  (if (null? tail)
	      #f
	      (loop (car tail)(cdr tail)))))))

;; given a spec apply some rules to a directory
;;
;;  WARNING: This function will REMOVE files - be sure your spec and path is correct!
;;
;; spec format:
;;   file-regex1 action; file-regex2 action; ...
;; e.g.
;;   .*\.log$ keep; .* remove
;;   --> keep all .log files, remove everything else
;; limitations:
;;   cannot have a rule with ; as part of the spec
;;   not very flexible, would be nice to return binned file names?
;; supported rules:
;;   keep     - keep this file
;;   remove   - remove this file
;;   compress - compress this file
;;
(define (common:dir-clean-up path spec-string #!key (compress "gzip")(actions '(keep remove compress))(remove-empty #f))
  (let* ((specs         (common:spec-string->list-of-specs spec-string actions))
	 (keepers       (make-hash-table))
	 (directories   (make-hash-table)))
    (find-files 
     path
     action: (lambda (p res)
	       (let ((rule  (common:file-find-rule p specs)))
		 (cond
		  ((directory? p)(hash-table-set! directories p #t))
		  (else
		   (case (vector-ref rule 1)
		     ((keep)(hash-table-set! keepers p rule))
		     ((remove)
		      (print "Removing file " p)
		      (delete-file p))
		     ((compress)
		      (print "Compressing file " p)
		      (system (conc compress " " p)))
		     (else
		      (print "No match for file " p))))))))
    (if remove-empty
	(for-each
	 (lambda (d)
	   (if (null? (glob (conc d "/.*")(conc d "/*")))
	       (begin
		 (print "Removing empty directory " d)
		 (delete-directory d))))
	 (sort (hash-table-keys directories) (lambda (a b)(> (string-length a)(string-length b))))))
    ))

;;======================================================================
;; E N V I R O N M E N T   V A R S
;;======================================================================
(define (bb-check-path #!key (msg "check-path: "))
  (let ((path (or (get-environment-variable "PATH") "none")))
    (debug:print-info 0 *default-log-port* (conc msg" : $PATH="path))