,        Unix  Linux -
         32768
(    short int).     -
   pid  .

    ,     -
  ,      -
.   32768     ,  
     .    -
,       ,   
  :     ,
  .        -
   ,      -
            //
sys/kernel/pid max.

          
  task_struct.  ,    , -
  ,     task_struct. ,
        , -
    ,       current.
         -
 .       task_struct -
,    ,    ,  -
   .   ,   
  ,     ,  
,   thread_info    .    -
  thread_info,        task_struct
.

  86   current   
13         thread_info.  -
      current_thread_info (). 
     .

movl $-8192, %
andl %esp, %eax

   current   
  task   thread_info:

current_thread_info()->task;

         
PowerPC (    RISC-  IBM), 
   current     2. 
     ,  ,    
86,      .     
       ,    
        .

  49