  alterartor   :

~ look-* ---  ,  
     .     
         woo- 
      . stdin/stdout/stderr 
        . ( 
    look-tty    ).   look --- ӣ 
        .

~ woocache ---  / woo.   
           (,
         woocache    
       ).  stdin/stdout/stderr 
        "" ,  stdin 
     ,  stdout  ,  stderr ģ
       .   "" 

~ chooser ---   woo -> hoo. 
        commander. stdin/stdout/stderr
        "" . commander
       ,   stdin  ,
       stdin chooser, stdout   stdin
     "" .     
     commander  .

~ brook ---    
     hoo    .  stderr
        ,      stderr
       (  executor).

~ executor ---   c  .
      . ""  
      starter, ..      
      .   "" .

~ probe ---      . 
          (  ) 
      .   .

~ starter ---   pipe-line.  
       .     ģ
     3      . stdin/stdout/stderr
            ,
           
            .
            
      ,     
      .       
        :
     
     %root ---      , 
      starter.

     %drop ---     
        .

