Practical application of multiprocessing systems

  With the advent of accessible multiprocessing systems has arisen at users: how to use power of computer technics. At use of the ordinary software the quantity of processors of system basically stands idle.
  As practical example can serve, for example transformation of musical files flacogg. It is possible, for example to use console inquiry:

for i in *.flac ; do oggenc --quality=10 "$i" ; done

  But at a considerable quantity of files standing idle processors slightly cause irritation. To estimate power of productive technics the parallel software is necessary.
  It is offered to use the good program in language Lisp2D which starts in parallel converting of the files concluded in directories. The quantity of simultaneously started problems will be always equal to quantity of processors.

(('freemans defclass) defvar
  n signal  lock  nwaitsignal)
('freemans  defmethod freemans  ()
  (nil  setq
    n (nil  nprocs)
    signal  ('signal  newobject)
    lock  ('lock  newobject)
    nwaitsignal (0  copy)))
('freemans  defmethod enter ()
  (lock progn
    (nil  when  (n  = 0)
      (nwaitsignal  +=  1)
      (signal wait  lock))
    (n  -=  1)))
('freemans  defmethod exit  ()
  (lock progn
    (n  +=  1)
    (nil  when  (nwaitsignal  >  0)
      (nwaitsignal  -=  1)
      (signal send))))
('string  defmethod flactoogg (q  freemans)
  (nil  let (s  (d  ('dir newobject this)))
    (nil  while ('s set (d  read))
      (nil  let ((fullname  (this + "/" s)) stat  type)
        ('stat  set (fullname stat))
        (nil  if  (nil  statp stat)
          ('type  set (stat file-type)))
        (nil  cond
          ((s = "."))
          ((s = ".."))
          ((type  = 'regular)
            (nil  let ((ss  (s  size)))
              (nil  if  (ss > 5)
                (nil  when  (((s  part  (ss - 5)) lower)  = ".flac")
                  (freemans enter)
                  (nil  fork
                    (nil  if  (0  = ("oggenc"  system  ("--quality="  + q)  fullname))
                      (fullname unlink)
                      (cerr writeln "crash oggenc for " fullname))
                    (freemans exit))))))
          ((type  = 'directory)
            (fullname flactoogg q freemans)))))
    (d  close)))
("."  flactoogg (arg first) ('freemans  newobject))

  High-grade loading of processors by useful work becomes result of use of in parallel started processes. And huge economy of personal time.