        ,
      (head),    -
      .     -
   ,      NULL.  -
      ,    
.       ,  
    .     -
      ,     -
  . ,     , 
          . 
     .

     Linux

  Linux       -
 .    ,     -
,        ,   
  ,      !  ,
       .    
      .   -
      ,   -
   .      -
       ,      
,     .     
  .  ,     -
 .       
     .     
  .

   ,        , 
. ,         
( task_struct      ).

  

       .    
         , 
  .      2.1  -
      .    
   .     -
        .

        <linux/list. h>, a
      .

struct list_head {

struct list head *next, *prev;

};

      list_head.  
,  ,      . ,

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