<title>Unix overview CHAP04</title>



     4

          



      㦥  뫮 祭   2,  䠩  ⥬ UNIX  㭨-
 .  ᮤন ଠ, 室    
⮣, ⮡   䠩, ਬ, ࠢ ᮡ⢥  䠩, ࠢ
㯠   䠩, ࠧ 䠩  ᯮ  䠩  䠩 -
.    䠩, ᯮ ⪮ ।  ⥬-
 맮   䠩 ப ᨬ,  㯠    ⢥
⠢    䠩.    ⠢  筮 । 䠩,
 祬  ⥬ ८ࠧ     䠩.
      饭 ᠭ ७  䠩   樮
⥬  UNIX,  ᫥饩   ᬠਢ 饭  樮
⥬, 易  ࠡ⪮ 䠩.  4.1 ᠥ   ࠡ
  , ࠧ 4.2 - ७   䠩   -
⮢, 易  ⥭   ஬ ଠ樨 䠩.  ࠧ 4.3
᫥ ஥ ⠫ -  ,   ࣠-
뢠 䠩 ⥬   娨 䠩, ࠧ 4.4 ᮤন 
८ࠧ  짮⥫᪨ 䠩  .  ࠧ 4.5  
 㯥࡫,   ࠧ 4.6  4.7 ।⠢  -
  䠩 ᪮ ᮢ  ᪮ . ,  ࠧ 4.8 
  㣨 ⨯ 䠩  ⥬,      䠩 ன.
    , ᠭ  ⮩ , ஢   ࠢ   -
  ࠢ   襬, ᬮ७묨  ।饩  (㭮
4.1).  iget 頥 ᫥   ஢  ᮢ  
 뢠   ᪠, ᯮ  ,   iput
᢮  .  bmap ⠭ ࠬ , 易 
饭  䠩.  namei ८ࠧ ⠢    짮⥫-
᪮ 䠩   , ᯮ  iget, iput 

        ࠡ  䠩 ⥬   ஢
    +--------------------+------------------+-----------------+
    |       namei        |                  |                 |
    +--------------------+  alloc    free   |  ialloc  ifree  |
    | iget   iput   bmap |                  |                 |
    +--------------------+------------------+-----------------+
    +---------------------------------------------------------+
    |              ࠡ  ࠬ                 |
    +---------------------------------------------------------+
    |    getblk     brelse     bread     breada     bwrite    |
    +---------------------------------------------------------+

             㭮 4.1.  䠩 ⥬


bmap.   alloc  free 뤥  ᢮ ᪮   䠩-
,  ialloc  ifree   ᢮  䠩 .



        4.1 

        4.1.1 ।

       ᪥  ᪮ ଥ    뢠    

                                     59

  ०, 祬    ࠡ. ᪮    ᥡ
᫥騥 :
  * 䨪  䠩. ࠢ ᮡ⢥ ࠧ  -
    㠫 楬  "㯯"  ⥬ ᠬ  । 
    짮⥫,  ࠢ 㯠   䠩.  㯥௮짮⥫  
    ࠢ 㯠  ᥬ 䠩  ⥬.
  *   䠩.    䠩 筮 ⨯, ⠫, ᯥ樠
    䠩, ᮮ⢥騬 ன⢠ -뢮 ᨬ   ,
      ⠪ ࠪ 䠩  (࣠騬 㦨 ᮢ 
    浪 㯫, " 襫 -  襫").
  * ࠢ 㯠  䠩. ⥬ ࠧ࠭稢 ࠢ 㯠  䠩  
      ᮢ 짮⥫: 㠫쭮  䠩, 㯯
       짮⥫;    뤥  ।
    ࠢ   ⥭,   ᯮ 䠩,  ⠭ -
    㠫쭮. ᪮ ⠫  䠩    ᯮ,  ࠧ-
    襭   ᯮ   砥   ࠢ ந-
       ⠫   䠩.
  *  ᢥ, ࠪਧ騥 ࠡ   䠩:  ६  ᥭ
    ᫥      䠩, ६ ᫥ 饭  䠩, ६
    ᥭ ᫥   .
  * ᫮ 㪠⥫  䠩, 饥 ⢮ ,  ᯮ㥬  
    ᪥ 䠩  娨 ⠫. ⥫  䠩 ஡ ᬠ-
       5.
  *  ᮢ  ᪥,   ᯮ ଠ 䠩. 
    짮⥫  ࠪ  ଠ   䠩  ᪨ ⮪ ⮢,
     ᯮ    ᮯਪ ᪮ .  ᪮-
     , ᮤঠ騥 ଠ 䠩, 㪠뢠  .
  *   䠩.   䠩    ᬥ饭   -
    ⥫쭮 砫 䠩, 稭  ᬥ饭, ࠢ 0, ⮬  ࠧ
    䠩     1  ᨬ쭮 ᬥ饭. ਬ, ᫨ -
    ⥫ ᮧ 䠩  뢠 ⮫쪮 1  ଠ樨   
    ᬥ饭 1000  砫 䠩, ࠧ 䠩 ⠢ 1001 .    -
        ⠢    䠩, 室  ⢫
    㯠  䠩.

            +---------------------------------------+
            |              mjb              |
            |              㯯 os                |
            |          ⨯ -  䠩           |
            |        ࠢ 㯠 rwxr-xr-x        |
            | ᫥ 饭 23  1984 13:45 |
            | ᫥  22  1984 10:30 |
            |  ४  23  1984 13:30  |
            |           ࠧ 6030             |
            |            ᪮             |
            +---------------------------------------+

              㭮 4.2. ਬ ᪮ 


     㭪 4.2  ᪮   ண  䠩.    
ਭ  筮  䠩,   ண - "mjb"  ࠧ ண -
6030 . ⥬ ࠧ蠥 짮⥫ "mjb" ந ⥭,  
ᯮ 䠩; 童 㯯 "os"  ᥬ ⠫ 짮⥫ ࠧ-
 ⮫쪮   ᯮ 䠩,   뢠   .  -
  ࠧ 䠩  ⠭ 23  1984   13:45,  ᫥
ࠧ ந 22  1984   10:30.     ᫥
ࠧ 23  1984   13:30,   ଠ   ६  䠩
 뢠.    襯᫥   . -

                                     60

   ࠧ稥     ᮤন   ᮤন
䠩. ন 䠩  ⮫쪮 ⮣,   䠩 ந -
. ন      ᮤন 䠩, ⠪ 
     䠩, ࠢ 㯠   㪠⥫. 
ᮤন 䠩 ⮬᪨ 뢠 ४ ,  ४
   砥  ᮤন 䠩.
       , ஬  ᪮ , 砥  ᥡ 
᫥騥 :
  * ﭨ   , ࠦ饥
    - ஢  ,
    -    ஢   - ,
    - ⫨砥  ।⠢     ᢮ ᪮  
      १  ᮤন ,
    - ⫨砥  ।⠢     ᢮ ᪮  
      १  ᮤন 䠩,
    - 室  䠩  孥 窥 (. ࠧ 5.15).
  * ᪨  ன⢠ 䠩 ⥬, ᮤঠ饩 䠩.
  *  .     ᪥ ࠭   ᨢ (.
    ࠧ 2.2.1),    ᪮    -
      ᨢ.  ᪮     㦭.
  * ⥫  㣨   .  뢠    --
    ।   砥   ᯨ᮪ ᢮ ᮢ  ⮬,  -
        -।  砥   ᯨ᮪ ᢮  -
    ஢.  -।   ᮮ⢥⢨  ᪨ ஬
    ன⢠  ஬ .   ᯮ      
         ᪮ ,    室 -
    ६   -।, ⠪   ᯨ᪥ ᢮ ᮢ.
  * 稪 뫮, 騩 ⢮ ⨢ ஢ 䠩 (⠪,
     ).
         ,  ன  ࠡ⠥   ,  -
     ,  ࠢ ᠬ 宦  ࠢ
ࠬ.  ⠪  ,  १ 祣 㣨 ᠬ -
頥 ࠡ  ;     ⠭      ᯥ樠
䫠,  騩    ⮬,   믮 ⨢   ᮢ
᫥ ,  ⮫쪮 ஢ 㤥  .  ⠭  㣨
䫠  ⬥砥 ⨢  ᪮ ᮬ     -
.    㦭 㤥    䠩  ,  -
९       ⮫쪮 ᫥ ஢ન  䫠.
     ࠧ⥫ ࠧ稥        -
    稥 稪 뫮, 뢠饣 ⢮ -
⨢ ஢ 䠩.  ⨢,   뤥 , -
,  ⨨ 䠩.  室  ᯨ᪥ ᢮ ᮢ, ⮫-
 ᫨ 祭  稪 뫮 ࠢ 0,   ,     
७ ᢮    㣮 ᪮ .  -
ࠧ, ᯨ᮪ ᢮ ᮢ 㯠  ஫   ⨢ -
ᮢ.  ᫨  ⠥   䠩, 祩     -
  ᭮ 㫥,  ७砥 ᢮      ᯨ᪠
  ᯮ짮  ⨬  ᮬ.  㣮 ஭,    稪
뫮;  室  ᯨ᪥ ᢮ ஢ ⮣  ⮫쪮 ⮣,  
 ࠧ஢.

        4.1.2 饭  ᠬ

         䠩 ⥬    
뤥       ᠬ ᮮ⢥ ⬮. 
iget 砥         (㭮  4.3);    
祭   getblk  ᪠ ᪮   ୮ . 
८ࠧ  ன⢠      -।    ᬠਢ
  -।   ᪠ . ᫨   㦥,  뤥

                                     61

    +------------------------------------------------------------+
    |  iget                                              |
    | 室 ଠ:     䠩 ⥬      |
    | 室 ଠ: ஢                 |
    | {                                                          |
    |   믮                                                |
    |   {                                                        |
    |     ᫨ (  ᭮ )                         |
    |     {                                                      |
    |       ᫨ ( ஢)                           |
    |       {                                                    |
    |         ਮ⠭ ( ᢮ );         |
    |         த;    /* 横  ᫮ த */   |
    |       }                                                    |
    |       /* ᯥ樠쭠 ࠡ⪠  祪 ஢      |
    |          ( 5) */                                      |
    |       ᫨ (  ᯨ᪥ ᢮ ᮢ)            |
    |           ᯨ᪠ ᢮ ᮢ;               |
    |       㢥 稪 뫮  ;                |
    |        ();                                 |
    |     }                                                      |
    |     /*    ᭮  */              |
    |     ᫨ (ᯨ᮪ ᢮ ᮢ )                  |
    |        (訡);                                 |
    |         ᯨ᪠ ᢮ ᮢ;      |
    |         䠩 ⥬;             |
    |        ன -।,   ;|
    |        ᪠ ( bread);               |
    |     樠஢  (ਬ, ⠭ 稪   |
    |      뫮  1);                                          |
    |      ();                                   |
    |   }                                                        |
    | }                                                          |
    +------------------------------------------------------------+

          㭮 4.3.  뤥 ᮢ  



  ᯨ᪠ ᢮ ᮢ   .  ⥬    ⮢  
⥭    ᪠   ,  ஬  頥.  㦥 
   ᪮ ன⢠    ᪮  
 ᪥, ᮤঠ饣 ,  ⮬ ⮣, ᪮쪮 ᪮ ᮢ -
頥   ᪮ . ᫥ ந  㫥

      = ((  - 1) / ᫮ ᮢ  ) +
                  + 砫   ᯨ᪥ ᮢ
   頥 楫  ⭮. ਬ, ।,
  2  砫  ᯨ᪥ ᮢ      -
  8  ᮢ,  ⮣   ஬ 8 室   2,   
஬ 9 -   3. ᫨   ᪮   16 ᮢ, ⮣-
   ࠬ 8  9 ᯮ  ᪮    ஬  2,  
  ஬ 17   ᮬ  ᪮  3.
    ᫨       ன⢠  ᪮ ,  ⠥ ,
ᯮ  bread ( 2), ⥬  ᬥ饭    -
    㫥:

    ((  - 1)  (᫮ ᮢ  )) *
    * ࠧ ᪮ 

                                     62

ਬ, ᫨  ᪮   64     
8  ᮢ,  ⮣    ஬ 8    ᬥ饭 448  
砫 ᪮ .  㡨ࠥ     ᯨ᪠ ᢮ -
ᮢ, 頥   ᮮ⢥ -।  ⠭  祭
稪 뫮 ࠢ 1.  ९뢠  ⨯ 䠩   䠩-
, ⠭ ࠢ 㯠, ᫮ 㪠⥫  䠩, ࠧ 䠩  ⠡
ᮢ   ᪮     頥 ஢  
.
     㫨  ஢    稪  뫮  ᨬ
   㣮. ஢ -  ⠭,    ६ -
 ⥬ 맮   楫   㣨  ᠬ  -
         ࠡ (  ࠭ ⨢稢 -
).  ᭨ ஢  砭 ࠡ⪨ ⥬ 맮: -
஢    室  ࠭ ⥬ 맮.  㢥-
稢 祭 稪 뫮    ⨢ 뫪  䠩.
ਬ,  ࠧ 5.1 㤥 ,   㢥稢 祭  -
稪  뫮  ⮣,      뢠 䠩.  㬥蠥 祭
稪 뫮 ⮫쪮 ⮣,  뫪 ⠭ ⨢,  ਬ,
   뢠 䠩.  ࠧ, ⠭ 稪 뫮 -
࠭  ⢠ ⥬ 맮. ஢ ᭨    
饭ﬨ    樮 ⥬, ⮡  ᠬ ६
ந ࠧ   䠩; ⠭ 稪 뫮  
  饭ﬨ  樮 ⥬, ⮡ ।। ७祭
஬ ⨢   .  ࠧ,   ஢  
ࠧ஢ 뤥  ᨬ  祭 稪 뫮. -
    ᢮  ᮢ   ⫨  open ⥬
樨,  祬   㡥   5.
       iget, ⨬,  ᫨  ⠥   -
  ᯨ᪠ ᢮ ᮢ  㦨 ᯨ᮪ ,  ᮮ頥
  訡.    ⮬ ⫨稥  , ன ᫥   ࠡ 
᪮묨 ࠬ,   ਮ⠭ ᢮ 믮   ,
   ᢮.  ஫ 뤥 ᮢ  -
⥫᪮ ஢ ।⢮ ᪠ ⥬ 権 open    close  
⮬      ࠭஢ ,   ⠭ 㯭.
⥫쭮, , ਮ⠭騩 ᢮ 믮    ᢮-
 ,    .  ᪮॥ ࢥ 믮-
  ⥬  맮, 祬 ⠢ ⠪   "襬" ﭨ.
,    ⠪ ஫  ࠬ. ᪮  
 㤥ঠ  ஢  祭 믮 ᪮쪨 ⥬-
 権,    ࠭஢ ᪮஥ ᢮  ,  
  ⮬ ਮ⠭  ⮣ ,   ⠭ -
.
     । ࠣ ᬠਢ 砩,     뤥
,  騩   ᭮ . ᫨  室  , -
 (A) 㦨   -।  ஢,  ஢    
㣨 ᮬ (B). ᫨  ஢,  A ਮ⠭
  ⠢  䫠     , 뢠,    ᢮
.    B ࠧ ,  "ࠧ㤨"  -
 (  A), 騥 ᢮ .    
  A ᬮ ᯮ짮 ,   , ⮡ 㣨 -
     . ᫨  ࢮ砫쭮  稪  뫮  
祭,  ࠢ 0,  ⠪   ᯨ᪥ ᢮ ᮢ, -
⮬  㡥  㤠:     ᢮.   㢥-
稢 祭 稪 뫮  頥 ஢ .
    ᫨  㬬஢    ᪠,  ⬥,   iget
 ⭮襭  砫쭮 ⠤ ⥬ 맮,    
頥    䠩.      頥  ஢ 
  祭 稪 뫮,  1 訬, 祬   뫮  ࠭.
    ᮤন ⥪ ଠ  ﭨ 䠩.  ᭨

                                     63

஢   । 室   ⥬  樨,  ⮬  㣨
⥬  맮    , ᫨ .   5 -
ਢ  砨  ஡.

    +------------------------------------------------------------+
    |  iput   /* ࠧ襭 㯠     */|
    | 室 ଠ:  㪠⥫              |
    | 室 ଠ:                            |
    | {                                                          |
    |    ஢  ᫨    ஢;       |
    |    㬥  1 稪 뫮  ;              |
    |    ᫨ (祭 稪 뫮 == 0)                    |
    |    {                                                       |
    |       ᫨ (祭 稪 痢 == 0)                 |
    |       {                                                    |
    |          ᢮ ᪮   䠩 (     |
    |           free, ࠧ 4.7);                               |
    |          ⠭ ⨯ 䠩 ࠢ 0;                    |
    |          ᢮  ( ifree, ࠧ 4.6);   |
    |       }                                                    |
    |       ᫨ ( 䠩 頫        |
    |         ᮤন 䠩)                        |
    |          ᪮४஢ ᪮ ;                  |
    |          ᯨ᮪ ᢮ ᮢ;        |
    |    }                                                       |
    |     ஢  ;                             |
    | }                                                          |
    +------------------------------------------------------------+

                 㭮 4.4. ᢮ 



        4.1.3 ᢮ ᮢ

     ⮬ 砥,    ᢮    (  iput,  㭮
4.4),    㬥蠥  祭  稪 뫮  . ᫨  祭
⠭ ࠢ 0,  ९뢠      ⮬  砥,  
    ⫨砥  ᪮ .  ࠧ, -
  ᮤন 䠩, ᫨  䠩 ந 饭  -
     䠩  ࠢ 㯠  䠩.  頥 -
  ᯨ᮪ ᢮ ᮢ,  䥪⨢  ᯮ    
    砩, ᫨  ᪮  .   ⠪ ᢮-
  易  䠩 ଠ樮   , ᫨ ᫮ 뫮
 䠩 ࠢ 0.


        4.2    

     㦥 ਫ,  砥  ᥡ ⠡ ᮢ  ᯮ
ଠ樨 䠩  ᪥.      ᪥   ᢮
,    ⮩ ⠡ ࠭ ᮢ㯭 ஢ ᪮ . ᫨
  䠩  뢭 ⮪  ᪥ (  䠩  
  ᫥⥫쭮 ᪮ ),   饭   
䠩  뫮   筮 ࠭    砫쭮   ࠧ
䠩. , ⠪ ⥣ ࠧ饭      ⢫
⮥ ७  ᦠ⨥ 䠩  䠩 ⥬  ᪠ ࠣ樨
᢮  ࠭⢠   ᪥.  ⮣,  諮  뤥-
  १ࢨ஢ 뢭 ࠭⢮  䠩 ⥬  ।  -

                                     64

 権,  ਢ  㢥祭 ࠧ 䠩.

   -------------+----------+----------+----------+-------------
     ---------- |   A  |   B  |   C  | -----------
   -------------+----------+----------+----------+-------------
               40         50         60         70
    

   -------------+----------+----------+----------+---------+---
     ---------- |   A  |  |   C  |   B | --
   -------------+----------+----------+----------+---------+---
               40         50         60         70        81
    

    㭮 4.5.  饭  뢭  䠩   ࠣ
                  ᢮ ࠭⢠


    ।,  ਬ,    짮⥫  ᮧ  䠩, A, B  C,
    10 ᪮ ,  ⠪  ⥬  뤥
  ࠧ饭    䠩 뢭 . ᫨ ⮬ 짮⥫
  5   ଠ樥  । 䠩, B,    ਤ
᪮஢ 䠩 B     䠩 ⥬,    ࠧ஬
15 .    ⠬ ᮢ  ஢ ⮩ 樨 -
  ,    ଠ樥 䠩 B, ⠭ ᯮ㥬묨, ᫨
⮫쪮    䠩 ࠧ஬   10  (㭮  4.5).
    ஢ ࠣ ࠭⢠ , ਮ᪨
᪠ 楤 ⪨ , 㯫騥  ,    -
ॡ  ⥫쭮 室 ६  ⥬ ᮢ.
      楫  襭    ᮥ  䠩   ,
 ଠ樨 䠩  ࠧᠭ  ᥩ 䠩 ⥬.  -
 奬 ࠧ饭 ᫮  ᪠ .  ᮢ  ᮤ-
 ᯨ᮪ ஢ , ᮤঠ ਭ 䠩 ଠ, 
  ᫥  뢠,   ᯨ᪮  䠩  
㤭 ࠢ. ᫨ ᪨   1 ,  䠩, -
  10 , ॡ    10 ஢ ,  䠩, -
饬  100 ,     100 ஢ .   
ࠧ    㤥  ஢    ᨬ  ࠧ 䠩, 
諮  ⠭ ⭮⥫쭮 ⪮ ࠭祭  ࠧ 䠩.
     ⮣, ⮡    﫠 ࠡ  -
 䠩, ⠡ ᮢ ᪮   ਢ    ᮮ⢥⢨  
ன,  ।⠢  㭪 4.6.  V ⥬ UNIX ࠡ⠥ 
13 窠 室  ⠡ ᮢ ,  ਭ樯   -
  ⢠ 祪 室. , 騩  "ﬠ " 
㭪, ᮤন  ᪮ ,   ࠭  ॠ  -
.  ,  騩    "ୠ ᢥ ", 㪠뢠 
, ᮤঠ騩 ᯨ᮪ ஢  אַ 樨. ⮡   
      ᢥ 樨,     ,
 ᮮ⢥騩 室   אַ 樨 , ⠢  אַ -
樨, 㦨 . , 騩  " ᢥ -
", ᮤন ᯨ᮪ ஢  ୮ ᢥ 樨,   ,
騩   "ன ᢥ ", ᮤন ᯨ᮪ ஢ -
  ᢥ 樨.
     ਭ樯,  ⮤  뫮  ࠭   প  -
 ⢥୮ ᢥ 樨,  ୮ ᢥ 樨  ⠪
,    ࠪ⨪ 뢠 筮 饩 . ।-
,  ࠧ ᪮   䠩 ⥬ 1        
  32  (4 ).     ࠭  256 -
஢  .  뢠 (㭮 4.7),  ᨬ ࠧ 䠩

                                     65

ॢ蠥 16 , ᫨ ᯮ짮   10  אַ 樨 
1 ୮ ᢥ 樨, 1  ᢥ 樨   1  ன
ᢥ 樨. ᫨  ,    "ࠧ 䠩"  
- 32 ,  ࠧ 䠩  ⢨⥫쭮 ࠭祭 4 ⠬ (2  -
 32).
       ଠ樨  䠩,  ᬥ饭  . 
ᬠਢ  䠩  ⮪ ⮢    ⮢, 稭  㫥-
   稢 ᮬ, ࠢ ࠧ 䠩.    室  
⮢  : 䠩 稭  㫥 ᪮   稢-
 ,  ண । 室  ࠧ 䠩.  -
    ॢ頥 ᪨ , ਭ騩 䠩,  ᮮ⢥-

                                                       ଠ樮-
                                                   
      +-------------+                                    +-----+
      | אַ . +----------------------------------->|     |
      |            0|                                    |     |
      +-------------+                                    +-----+
      | אַ . +-----------------+                  +-----+
      |            1|                 +----------------->|     |
      +-------------+                                    |     |
      | אַ . +-----------------+                  +-----+
      |            2|                 |                  +-----+
      +-------------+                 +----------------->|     |
      | אַ . +-----------------+                  |     |
      |            3|                 |                  +-----+
      +-------------+                 |                  +-----+
      | אַ . |                 +----------------->|     |
      |            4|                                    |     |
      +-------------+                                    +-----+
      | אַ . |                                       -
      |            5|                                       -
      +-------------+                                       -
      | אַ . |                                       -
      |            6|                                       -
      +-------------+                                    +-----+
      | אַ . |                 +----------------->|     |
      |            7|                 |                  |     |
      +-------------+  +--------------+                  +-----+
      | אַ . |  |                                 +-----+
      |            8|  |              +----------------->|     |
      +-------------+  |              |                  |     |
      | אַ . +--+  +------+    |                  +-----+
      |            9|     +------+----+                  +-----+
      +-------------+  +->+------+               +------>|     |
      |  ୮  +--+  +------+               |       |     |
      |ᢥ |     +------+               |       +-----+
      +-------------+  +->+------+ +->+------+   |       +-----+
      |      +--+  +------+ |  +------+   |    +->|     |
      |ᢥ |     +------+ |  +------+   |    |  |     |
      +-------------+     +------+-+  +------+---+    |  +-----+
      |   ன   +--+  +------+    +------+        +---+
      |ᢥ |  +->+------+ +->+------+ +>+------+-+
      +-------------+     +------+ |  +------+ | +------+
                          +------+-+  +------+ | +------+
                          +------+    +------+-+ +------+
                          +------+    +------+   +------+

      㭮 4.6.  אַ  ᢥ 樨  

                                     66


     +----------------------------------------------------------+
     | 10  אַ 樨  1   = 10  |
     | 1  ᢥ 樨  256  אַ          |
     |                                  樨 =   256  |
     | 1   ᢥ 樨  256          |
     |                        ᢥ 樨 =    64 |
     | 1  ன ᢥ 樨  256          |
     |                 ᢥ 樨 =    16  |
     +----------------------------------------------------------+

      㭮 4.7. ꥬ 䠩    ࠧ  1 


    +------------------------------------------------------------+
    |  bmap  /* ⮡ࠦ  ᬥ饭     |
    |                   砫 ᪮ 䠩     |
    |                    䠩 ⥬ */                    |
    | 室 ଠ:  (1)                             |
    |                      (2) ᬥ饭                   |
    | 室 ଠ: (1)    䠩 ⥬    |
    |                      (2) ᬥ饭        |
    |                      (3) ᫮  -뢮      |
    |                      (4)    த        |
    | {                                                          |
    |     ᫨  ᪮   䠩 室     |
    |        ᬥ饭  ;                         |
    |     ᫨  砫쭮     -    |
    |       뢮;                 /* 室 ଠ 2 */  |
    |     ᫨ ⢮   ஢ 짮-    |
    |       ⥫;                   /* 室 ଠ 3 */  |
    |     ஢  ⥭  த,   |
    |       ;                 /* 室 ଠ 4 */  |
    |     । ஢ ᢥ;                        |
    |     믮 ( ஢ ᢥ 㣮)            |
    |     {                                                      |
    |          । 㪠⥫     ᢥ |
    |            樨 室   ᪮    |
    |            䠩;                                          |
    |            ᪮       |
    |             ᢥ 樨;                      |
    |          ᢮   , 祭  १-  |
    |             믮 ।饩 樨 ⥭     |
    |            ᪠ ( brelse);                        |
    |          ᫨ (᫮ ஢ ᢥ ௠)        |
    |                 ( );                   |
    |           ᪮  ᢥ 樨 (-  |
    |             bread);                                    |
    |          ⠭  ᪮   䠩 室 |
    |             ஢ ᢥ;                          |
    |     }                                                      |
    | }                                                          |
    +------------------------------------------------------------+

    㭮 4.8.  ८ࠧ   ᬥ饭    
                  䠩 ⥬




                                     67

騩  ᪮  .  㭪 4.8 ।⠢  bmap 
ᬥ饭    砫 䠩   䨧᪮   ᪥.
    ᬮਬ ଠ 䠩   (㭮 4.9)  ।,  ᪮-
   1024 . ᫨  㦭   ,  -
饬  ᬥ饭    砫  䠩, ࠢ 9000,  १ ᫥ 
室  뢮,    ᯮ    אַ  樨  
஬  8 (稭  0). ⥬  頥    ஬ 367; 808-
  ⮬
 (᫨    0)   9000- ⮬  䠩. ᫨ -
 㦭   , 㪠 ᬥ饭 350000      砫
䠩,      ᢥ 樨,   -
      9156.    ᢥ 樨    256
஢ ,  ⮬,  ஬ 㤥 祭    १
-

    +-------------+
    |    4096     |
    +-------------+
    |     228     |
    +-------------+
    |    45423    |
    +-------------+
    |      0      |
    +-------------+
    |      0      |
    +-------------+                      +----------->+------+
    |    11111    |                      |            |      |
    +-------------+                      |            |      |
    |      0      |                      |            |      |
    +-------------+                      |            +------+
    |     101     |                      |               367
    +-------------+                      |            ଠ-
    |     367     +----------------------+              
    +-------------+                                     
    |      0      |                  +->+------+
    +-------------+  +---->+------+  |  |      |  +-->+------+
    |     428     |  |     | 331  +--+  |      |  |   |      |
    +-------------+  |    0+------+   75+------+  |   |      |
    |    9156     +--+     |      |     | 3333 +--+   |      |
    +-------------+        +------+     +------+      +------+
    |     824     |          9156       |      |        3333
    +-------------+              +------+      ଠ-
                                 331           
                                       ୠ        
                                       

       㭮 4.9. 饭   䠩   


    ᢥ 樨, 㤥   ஬ 272384 (256 +
10);  ⠪ ࠧ,   ஬ 350000 㤥     -
 樨  77616. ᪮   ୮ ᢥ  -
樨        256 ⠬,   ஬ 350000 
ᯮ  㫥  ୮ ᢥ 樨    -
 ᢥ 樨,     331.      אַ
樨     ୮ ᢥ 樨 ࠭ 1 ,  
஬ 77616 室  75-  אַ 樨      ୮
ᢥ  樨,     3333. ,   ஬  䠩
350000    3333  816.

                                     68

     襬 ᬮ७ 㭪  4.9  㦨,    ᪮쪮
室      祭 0   ,    -
  ଠ    ᪨  .   , ᫨ 
ᮮ⢥騥  䠩   뢠  ଠ      ⮩
稭    ஢   ⠫  ࢮ砫 㫥 祭. 
⠪  ࠭⢮  ᪥  뤥.  ᯮ -
  䠩 뢠 ᠬ, ᪠騬 ⥬ 樨  lseek  
write  (. ᫥ ).  ᫥饩  ⠪ ,  -
ࠧ  ࠡ뢠 ⥬ 맮 樨 read,      ன
ந 饭  .
    ८ࠧ  ᮢ  訬 ᬥ饭ﬨ,  ⭮  ᯮ짮-
  ன ᢥ 樨,  ᫮ 楤ன, ॡ-
饩   饭 㦥  ६ ᪮        
ଠ樮  .  ᫨  㦨   ୮ , -
 ⠭ ண饩, ⠪   ਤ ⭮  
 ୮   ਮ⠭ ᢮ ࠡ    ஢
  ஢.  ᪮쪮 䥪⨢    ࠪ⨪ ?   
⮣,  ᯮ ⥬,  ⠪  ⮣,    짮⥫
    ⠢  ,  뢠騩  ॡ   ⮬ 饭 
訬 , , 쪨  䠩.  ,    㦥  뫮  祭
[Mullender 84], 設⢮ 䠩  ⥬ UNIX  ࠧ,  ॢ-
騩  10    1  ! (*) ᪮ 10  䠩 ᯮ 
 אַ 樨,  襩  , ࠭  䠩, 
 ந   饭  .⮬  ⫨稥  饭
 訬 䠩, ࠡ  䠩 ⠭⭮ ࠧ ⥪ .
      䨪 ⮫쪮  ᠭ    ।ਭ-
 ⪠ ᯮ짮 ࠧ ࠪ⨪ 䠩. ᭮ ਭ樯 
ॠ樨  䠩  ⥬  BSD  4.2 [McKusick 84] ⮨  ⮬,  祬
 ꥬ ,          饭
 , ⥬ ॥ ⥪ ࠡ  䠩.  ᢨ⥫  
㢥祭  ࠧ ᪮   ᪥, ⮬  ⥬ BSD ࠧ-
蠥  ᪨  ࠧ஬ 4   8  .  ,  㢥祭
ࠧ   ᪥ ਢ  㢥祭 ࠣ樨 ,  -
ன  ⥫  ⪨  ᪮ ࠭⢠  ᯮ㥬묨.
ਬ, ᫨ ࠧ ᪮  8  ,  ⮣  䠩  ࠧ஬  12
   1     ண . 㣠  -
ண  (4 ) 䠪᪨ ; 㣨 䠩     ᯮ짮-
   ࠭ . ᫨ ࠧ 䠩 ⠪,  ᫮ , -
    ᫥  ,  ࠢ୮ । 稭, 
।  ᪮ ࠭⢠ ⠢       䠩;
ꥬ  塞 ᪮ ࠭⢠ ⨣  䠩 ⥬  -
᪨  ࠧ஬ 4  45% [McKusick 84]. 室  ⮩  樨
  ⥬ BSD ⮨  뤥 ⮫쪮   (ࠣ)  ࠧ-
饭 ⠢襩 ଠ樨 䠩.  ᪮      ᥡ
ࠣ,  ਭ騥 ᪮쪨 䠩.  ஡ ⮩ ॠ-
樨 ᫥  ਬ ࠦ   5.
    ன 䨪樥 ᬮ७ ᪮   -
  ࠭   ଠ樨 䠩 (. [Mullender 84]). ᫨  㢥-
  ࠧ  ⠪, ⮡    ᪮ , -
     ᯮ짮  ᮡ⢥  , 
⠢  -  ࠭  䠩          
࠭  䠩  楫. ᭮ २⢮ ⠪ 室 砥 
⮬,  室 ⮫쪮  饭    뢠    
ᥩ ଠ樨, ᫨ 䠩 頥  ᭮ .
---------------------------------------
(*)    ਬ  19978 䠩    ,  ਡ-
    ⥫쭮 85% 䠩  ࠧ  8   48%  -    1  .
    ᬮ  ,       ॠ樨 ⥬ 
    㣮,   ॠ権 ⥬ UNIX  ⥫.

                                     69




        4.3 

       1 ,  ⠫  䠩,   ந
᪠  䠩 ⥬;    ஫  ॢ-
  䠩   . ⠫ -  䠩, ᮤন ண -
  ᥩ,       䠩, 祭
 ⠫. ⠢  -  ப ᨬ,    ᨬ-
  ࠧ塞  ⮩ ("/")  ᪮쪮 .  -
,  ஬  ᫥,    ⠫,  ᫥ -
    䠩,  饣 ⠫.  ᨨ V  ⥬
UNIX        ࠭稢 14 ᨬ; ⠪ ࠧ,
  2 ⠬, ⢮묨   , ࠧ  ⠫ -
⠢ 16 .

        +-----------------------------------------------+
        | 饭                |
        |   ⠫       (2 )      䠩   |
        +--------------------+---------------+----------+
        |          0         |       83      | .        |
        |         16         |        2      | ..       |
        |         32         |      1798     | init     |
        |         48         |      1276     | fsck     |
        |         64         |       85      | clri     |
        |         80         |      1268     | motd     |
        |         96         |      1799     | mount    |
        |        112         |       88      | mknod    |
        |        128         |      2114     | passwd   |
        |        144         |      1717     | umount   |
        |        160         |      1851     | checklist|
        |        176         |       92      | fsdbld   |
        |        192         |       84      | config   |
        |        208         |      1432     | getty    |
        |        224         |        0      | crash    |
        |        240         |       95      | mkfs     |
        |        256         |      188      | inittab  |
        +--------------------+---------------+----------+

               㭮 4.10. ଠ ⠫ /etc


     㭪 4.10  ଠ ⠫ "etc".   ⠫ 
䠩,  ⢥   㪠 窠   窨 ("."  "..")   -
 ᮢ   ᮢ  ࠬ ᮢ  ⠫  -
⥫᪮ ⠫, ᮮ⢥⢥.    䠩 "."  ⠫
"/etc"        ᬥ饭 0  祭 83.    䠩
".."    ᬥ饭 16  砫 ⠫  祭 2.    
⠫     묨,  ⮬   ࠢ 0. ਬ, -
  ᮬ 224  ⠫ "/etc" , ᬮ  ,      -
-  ᮤঠ  室  䠩   "crash". ணࠬ mkfs -
樠 䠩 ⥬ ⠪ ࠧ,   ᮢ    䠩
"."   ".."  ୥ ⠫ ᮢ  ஬ ୥  䠩-
 ⥬.

     ࠭   ⠫ ⠪ ,      䠩 筮-
 ⨯, ᯮ      ஢ﬨ אַ  ᢥ
樨.      ⠫ ⠪   ࠧ,  

                                     70

     䠩,  ᪫⥫쭮 ࠢ   ⠫ -
ࢨ ஬,  祬 ᯥ稢 ࠢ쭮   -
⠫.  ࠢ  㯠   ⠫  ᫥騩 : ࠢ ⥭ 
ᠬ     ⠫; ࠢ   -
 ᮧ    ⠫  㤠  (    -
⥬  権  creat, mknod, link  unlink),  १ 祣 
ᮤন ⠫; ࠢ ᯮ   ந  
⠫   䠩 (᪮  "ᯮ"  ⠫  ᫥).  
ਬ ࠦ 4.6  ࠧ  ⥭  ᪮  ⠫.


        4.4     ( )
                     


    砫쭮  饭  䠩 ந   ⠢  (
 ᪠),    open, chdir ( ⠫)   link.  -
   ⥬  ࠡ⠥  ᠬ,     ⥩ -
,  ८ࠧ  ⥩ ᪠  䨪 ᮢ, ⮡ -
   䠩.  namei ந   -
⠢ , ⠢  ᮮ⢥⢨      ⠫
   殢  䨪       
᪠ (㭮 4.11).
        2  ,    易  ⥪騬 ⠫ (
⥪   ࠬ); ࠡ , ⢥    짮-
, ᮤন 㪠⥫   ⥪饣 ⠫. 騬 ⠫ ࢮ-
    ᮢ    ⥬, 㫥 ,  ୥ ⠫.
  ⥪饬 ⠫      砫    ⥪饣
⠫ , 饣 த⥫᪨  ⭮襭   (. ࠧ-
  5.10).   ⥪騩 ⠫, 訢 믮 ⥬-
 樨 chdir ( ⠫).  ᪨ 䠩   稭
 ⥪饣 ⠫ , ᫨ ⮫쪮    ᪠    ।
 ⮩, 㪠뢠,   㦭 稭  ୥ ⠫. 
 砥    㦨  ⠫,  ண 稭-
  . 騩 ⠫ ࠭  ࠡ祩  ,  ୥
 ⥬ ࠭  쭮 ६ (**).
     namei ᯮ   ⠢   ᪠  -
  ;    ࠡ稬 ᠬ.  ⠫, 㤠
  砫,   ࠡ稬  ᮬ.      樨
横  ⬠  ஢ ᮢ ࠡ祣   ᮬ -
.  ⨢ 砥, 訫  ⢥ত,   ⮫쪮  䠩,  
騥  ⠫,   ﬨ ॢ 䠩 ⥬. 
⠪   ࠢ ந   ⠫ (ࠧ襭   ⥭
筮).  䨪樨 짮⥫    ᮮ⢥-
  㠫쭮  㯯 -
  䠩    ।⠢ ࠢ ᯮ,   㦭
ࠧ ᥬ 짮⥫.  ⨢ 砥,   .
     믮   䠩  ⠫, 樨஢   ࠡ-
稬  ᮬ,       ᪠ 室 -
  ⠫. 室   ᬥ饭    ⠫ (稭
 0),  । ⮯ ᪮   ᮮ⢥⢨    -
⬮ bmap  뢠  , ᯮ  bread.   -


---------------------------------------
(**)  ⮡   ᥡ ୥ ⠫ 䠩 ⥬,  -
       ⥬  chroot.  祭   ࠭-
       ࠡ祩  .


                                     71

    +------------------------------------------------------------+
    |  namei /* ॢ饭   ᪠   */|
    | 室 ଠ:    ᪠                       |
    | 室 ଠ: ஢                 |
    | {                                                          |
    |    ᫨ ( ᪠  砫  )                 |
    |         ࠡ稩  =   ( iget);    |
    |     ⨢ 砥                                      |
    |         ࠡ稩  =  ⥪饣 ⠫         |
    |          ( iget);                                  |
    |                                                            |
    |    믮 (  ᪠  稫)                |
    |    {                                                       |
    |          ᫥    ᪠;    |
    |         ஢ ᮮ⢥⢨ ࠡ祣  ⠫   |
    |           ࠢ 㯠;                                  |
    |         ᫨ (ࠡ稩  ᮮ⢥   -  |
    |            "..")                                 |
    |              த;  /* 横  ᫮ த */|
    |          ⠫ (ࠡ稩 ),  -   |
    |           bmap, bread  brelse;                       |
    |         ᫨ ( ᮮ⢥   ⠫   |
    |          (ࠡ祬 ))                                |
    |         {                                                  |
    |                  ᮢ襩 -|
    |               ;                                          |
    |              ᢮ ࠡ稩  ( iput);    |
    |              ࠡ稩  =  ᮢ襩  |
    |               ( iget);                             |
    |         }                                                  |
    |          ⨢ 砥  /*       |
    |                                ⠫ */                 |
    |               ( );                     |
    |    }                                                       |
    |     (ࠡ稩 );                            |
    | }                                                          |
    +------------------------------------------------------------+

    㭮 4.11.  ॢ饭   ᪠  


  ந   , ।⠢ ᮤন   ᫥-
⥫쭮 ᥩ ⠫.  㦥 ᮢ  ९뢠
       窨 室, ᢮  ( brelse) 
 ࠡ稩  ( iput),  ७砥   -
 ( iget).   ⠭ ࠡ稬 ᮬ. ᫨ 
 室   室饣 ,  ᢮ , ਡ  -
 ᬥ饭 ᫮ ⮢  , ॢ頥   ᬥ饭   
᪮   ( bmap)  ⠥ ᫥騩 .   
楤   ,     ᪠  ᮢ    
窨 室  ⠫,    ,   㤥 ⨣  -
.
    ।,  ਬ,    㦭  䠩 "/etc/ passwd".
  稭 ஢  䠩,  ⠫   
  ("/")   砥   ⥬.  ७ ⥪騬 ࠡ稬
ᮬ,  ⠫  ப "etc". ஢ਢ ᮮ⢥⢨ ⥪饣
 ⠫ ("/")  稥   ࠢ ந    -
,      ୥ ⠫ 䠩   "etc".  ᬠਢ
୥ ⠫     ᫥    ,    

                                     72

㦨   室  䠩 "etc".    室,  ᢮-
 , ⢥   ( iput),  뤥    䠩
"etc"  ( iget)  ᮮ⢥⢨  ஬   㦥 -
. ⮢ਢ  ⮬,  "etc"  ⠫,  ⠪  ⮬,  
  室  ࠢ  ந  ,   ᬠਢ ⠫
"etc"     ᪠ , ᮮ⢥饩 䠩 "passwd".  ᫨
ᬮ  㭮 4.10,  㢨,    䠩 "passwd" -
  ⮩   ⠫. 㦨 ,  ᢮ , -
 䠩 "etc",  뤥  䠩 "passwd", ᫥  祣  -  -
   ᪠ ௠ - 頥   .
    ⢥      䥪⨢  ᪠  ⠫
, ᮮ⢥饩    ᪠.   뢠  (.
[Ritchie  78b], .1968),    䥪⨢, ᪮  -
祭 ࠧ஬ ⠫.  ⮣, ࠭ ᨨ ⥬ UNIX   ࠡ⠫
   設  訬 ꥬ , ⮬ ⥫ 㯮  ᤥ-
   , ⠪    ᪠.   ᫮-
 奬 ᪠ ॡ  ⫨筮,  ᫮,  ⠫,
   ࠡ⠫      ⠫  ࠢ 
奬  ᪠.


        4.5 

        ⮩  뢠  䠩,  ⮬  ।-
,   ।⥫쭮 뢠  䠩   㦥 뫨 ।-
  ᪮ , ᮤঠ騥 ଠ.  ᫥ ࠧ 뢠-
,  ࠧ  砥   ᪮ . ⮡   
, ᬮਬ  㯥࡫.
    㯥࡫ ⮨  ᫥ :
    * ࠧ 䠩 ⥬,
    * ⢮ ᢮   䠩 ⥬,
    * ᯨ᮪ ᢮ ,   䠩 ⥬,
    *  ᫥饣 ᢮   ᯨ᪥ ᢮ ,
    * ࠧ ᯨ᪠ ᮢ,
    * ⢮ ᢮ ᮢ  䠩 ⥬,
    * ᯨ᮪ ᢮ ᮢ  䠩 ⥬,
    * ᫥騩 ᢮   ᯨ᪥ ᢮ ᮢ,
    * ஢   ᯨ᪠ ᢮   ᢮ ᮢ,
    * 䫠, 뢠騩,   㯥࡫ 뫨 ᥭ .

      ⠢襩     㤥 ᭥,  짮 ᨢ,
㪠⥫ﬨ   ஢.  ਮ᪨  ९뢠  㯥࡫
  , ᫨  㯥࡫ 뫨 ᥭ ,  ⮣, ⮡ ᯥ-
 ᮣᮢ  묨, ࠭騬  䠩 ⥬.


        4.6    

     뤥 ⭮ ,   ,  ண  ।-
⥫쭮  ।  ᮡ⢥   (  䠩 ⥬),  -
  iget.  ⬥ namei, ਬ,   ।  
,  ⠭  ᮮ⢥⢨    ⮩   ᪠ 
  ⠫. 㣮 , ialloc, 믮  祭  ᪮
  ᮧ 䠩.
     㦥 ਫ   2,  䠩 ⥬   ᯨ᮪
ᮢ.  ⠥ ᢮, ᫨   ⨯ ࠭ 㫥 -
祭.  ᫨      ,  ⥮᪨  
ந  ᢮   ᯨ᪥ ᮢ. ,  ⠪  
襫    ண,  ᪮ ॡ   襩   

                                     73

⥭ (⨬,  ᪠)   .  襭 ந⥫쭮-
  㯥࡫ 䠩 ⥬ ࠭ ᨢ ஢ ᢮  ᮢ
 䠩 ⥬.
      㭪  4.12 ਢ  ialloc 祭  ᮢ. 
稭,     ,  ᭠砫 ஢,   -
    -  ᢮ 饭 ᯨ᮪ ᢮ ᮢ  -

    +------------------------------------------------------------+
    |  ialloc   /* 뤥  */                  |
    | 室 ଠ:  䠩 ⥬                      |
    | 室 ଠ: ஢                 |
    | {                                                          |
    |   믮                                                |
    |     {                                                      |
    |       ᫨ (㯥࡫ ஢)                        |
    |       {                                                    |
    |          ਮ⠭ ( 㯥࡫  ᢮);  |
    |          த;   /* 横  ᫮ த */   |
    |       }                                                    |
    |       ᫨ (ᯨ᮪ ᮢ  㯥࡫ )             |
    |       {                                                    |
    |          ஢ 㯥࡫;                          |
    |              ᪠ ᢮   |
    |            ᮢ;                                       |
    |          ᪠  ᪥ ᢮    , |
    |            㯥࡫  ,     - |
    |              ᢮  ( bread    |
    |            brelse);                                        |
    |           ஢  㯥࡫;                    |
    |           믮  ( ⮫쪮 㯥-|
    |             ᢮);                              |
    |          ᫨ ( ᪥  ᢮ )     |
    |             ( ᮢ);                      |
    |             訬 ஬ । -  |
    |              ᫥ ᪮ ᢮ - |
    |            ᮢ;                                            |
    |       }                                                    |
    |       /* ᯨ᮪ ᮢ  㯥࡫   */           |
    |           ᯨ᪠ ᮢ  㯥࡫- |
    |         ;                                                |
    |         ( iget);                     |
    |       ᫨ ( ᫥ ᥣ ⮣  ᢮) /* !!! */|
    |       {                                                    |
    |          ९   ;                        |
    |          ᢮  ( iput);                |
    |          த;   /* 横  ᫮ த */   |
    |       }                                                    |
    |       /*  ᢮ */                                |
    |       樠஢ ;                             |
    |       ९   ;                           |
    |       㬥 稪 ᢮ ᮢ  䠩 - |
    |         ⥬;                                              |
    |        ();                                 |
    |     }                                                      |
    | }                                                          |
    +------------------------------------------------------------+

           㭮 4.12.  祭  ᮢ


                                     74

࡫. ᫨ ᯨ᮪ ஢ ᮢ  㯥࡫  ,   砥
  ᫥饣 , 뤥   祭 ᪮ 
᢮   , ᯮ  iget (      ᪠,
᫨  室),   ᪮   , 樠  
  頥  ஢. ⥬  ४  ᪮-
  , 㪠뢠,    ந諮 饭. 㫥 祭
 ⨯ 䠩   ⮬,  ᪮   祭.    ⥩襬
砥   ᮬ   浪,   ᫮ ७樨  -
 ஢ ⥫ ஢ப,  祬   ⪮  ⠭.
㡮  , ७ ,  ᪮쪮 ᮢ  -
  騥 ଠ樮 , ⠪  १   ।-
 믮 ᮢ,      稭 -
 ஢.  ।, ਬ,     
㦥 ᯮ㥬 . ७ 易  ஡   ᪫-
, ᠭ   2,   砭: ࠧ 奬 ஢ -
  ஡    ᪫祭,      ᠬ  ᥡ  
஡ ७樨.
    ᫨ ᯨ᮪ ᢮ ᮢ   㯥࡫  ,    ᬠਢ
  頥  㯥࡫    ஢ ᢮ ᮢ. 
⮬      뢠   ᪠   ᯨ᮪ -
஢ ᮢ  㯥࡫  ⪠,    ஬,  訬
।  .      "";  ᫥ ,
ᠭ  㯥࡫.  ᫥騩 ࠧ,   㤥  ᪠    ᪥
᢮  ,    ᯮ    ⢥ ⮢
窨,  祬 ࠭,    ਤ    ६
 뢠 ᪮ ,  -
 ᢮  猪 . ᫥ ନ஢  -
  ஢  ᢮ ᮢ  ᪠  祭  
ᠬ 砫. 直 ࠧ,   砥 ᪮ ,   㬥-
蠥 祭 稪 ᢮ ᮢ, ᠭ  㯥࡫.
    ᬮਬ    ᨢ ஢ ᢮ ᮢ (㭮 4.13).
᫨ ᯨ᮪ ᢮ ᮢ  㯥࡫   ࢮ ᨢ  -
㭪 4.13()  祭  ஬,  祭 㪠⥫  ᫥-
騩   㬥蠥  18  롨ࠥ   ஬  48.  ᫨
  ᯨ᮪  룫廊   ᨢ  㭪 4.13(),  , 
ᨢ     ᪠ ᢮ ᮢ  ,  ⮬ 
㤥 ந, 稭    ஬ 470,   ࠭  -
.     ᯨ᮪ ᢮ ᮢ  㯥࡫  ⪠-

    ᮪ ᢮ ᮢ  㯥࡫
    +---------------------+------+------+-------------------+
    |  ᢮   |      |      |            |
    |<>|  83  |  48  |<>|
    +---------------------+------+------+-------------------+
                          18     19     20           ᨢ 1
                                        ^
                                        | 㪠⥫

    ᮪ ᢮ ᮢ  㯥࡫
    +---------------------+------+------+-------------------+
    |  ᢮   |      |      |            |
    |<>|  83  |  <|>|
    +---------------------+------+------+-------------------+
                          18     19     20           ᨢ 1
                                 ^
                                 | 㪠⥫

      () 祭 ᢮   । ᯨ᪠


                                     75

    ᮪ ᢮ ᮢ  㯥࡫
    +------+------------------------------------------------+
    |  470 |                                         |
    |<|>|
    +------+------------------------------------------------+
    0                                               ᨢ 1
    ^       
    |㪠⥫ ( )
            
         
    ᮪ ᢮ ᮢ  㯥࡫
    +------+------------------------------+-----+-----+-----+
    |  535 |           ᢮   | 476 | 475 | 471 |
    |<||||>|
    +------+------------------------------+-----+-----+-----+
    0                                     48    49    50
                                                            ^
                                                  㪠⥫ |

      () 祭 ᢮ ,   ᯨ᮪  㯥-
           

       㭮 4.13.  ᨢ ஢ ᢮ ᮢ

,   ᫥   ⢥ 砫쭮 窨  ᫥
ᬮ஢ ᪠.  ந 祭 䠩 ⮫쪮   ࠭  
᪠   ( ஬ 471  㭪)  த ࢠ ࠡ-
.

    +------------------------------------------------------------+
    |  ifree     /* ᢮  */              |
    | 室 ଠ:     䠩 ⥬      |
    | 室 ଠ:                            |
    | {                                                          |
    |    㢥  1 稪 ᢮ ᮢ  䠩    |
    |      ⥬;                                              |
    |    ᫨ (㯥࡫ ஢)                           |
    |          ࠢ;                             |
    |    ᫨ (ᯨ᮪ ᮢ )                         |
    |    {                                                       |
    |         ᫨ (    , -  |
    |             ᫥饣 ᬮ)              |
    |                ᫥饣 ᬮ     |
    |                 ;                         |
    |    }                                                       |
    |     ⨢ 砥                                      |
    |         ࠭    ᯨ᪥ ᮢ;         |
    |     ࠢ;                                  |
    | }                                                          |
    +------------------------------------------------------------+

             㭮 4.14.  ᢮ 


     ᢮  ஥ ⥫쭮  .  稢  
  饥 ⢮ 㯭  䠩 ⥬ ᮢ,  ஢-
 稥 ஢  㯥࡫. ᫨  ஢, , ⮡ -
 ७,  ᮮ頥:     -
࡫,       ᪥  㯥    ७-

                                     76

. ᫨ ᯨ᮪  ஢,  ஢,     
஢ ᮢ  ᫨ , 頥    ᯨ᮪  室  -
⬠. ᫨ ᯨ᮪ ,   ᬮ   ࠭  ᢮-
  .  ࠢ  ᢮   ஬ -
 . ᫨  ᢮     ,
    ᢮ , 뢠  㯥࡫
 ண  .   , ᪮  
 , ᬠਢ ᯨ᮪ ᮢ  ᪥.  ন -
  ᯨ᪠  㯥࡫ ⠪ ࠧ,  ᫥ , 롨ࠥ  
ᯨ᪠,     .      ᢮
ᮢ  ࠬ, -

    +------+------------------------------+-----+-----+-----+
    |  535 |           ᢮   | 476 | 475 | 471 |
    |<||||>|
    +------+------------------------------+-----+-----+-----+
    0   ^                                 48    49    50
        |                                                   ^
                                 㪠⥫ |

    () ࢮ砫  ᯨ᪠ ᢮ ᮢ  㯥-
        

    +------+------------------------------+-----+-----+-----+
    |  499 |           ᢮   | 476 | 475 | 471 |
    |<||||>|
    +------+------------------------------+-----+-----+-----+
    0   ^                                 48    49    50
        |                                                   ^
                                 㪠⥫ |

    () ᢮   499

    +------+------------------------------+-----+-----+-----+
    |  499 |           ᢮   | 476 | 475 | 471 |
    |<||||>|
    +------+------------------------------+-----+-----+-----+
    0   ^                                 48    49    50
        |                                                   ^
                                 㪠⥫ |

    () ᢮   601

    㭮 4.15. 饭 ஢ ᢮ ᮢ  㯥-
                  


訬, 祬   ,    ᪫祭.
    ᬮਬ  ਬ ᢮ ᮢ. ᫨    ᯨ᪥  ᢮
ᮢ    㯥࡫       ஢ ᢮ ᮢ
(  㭪 4.13()),  頥  ᯨ᮪   ,  ⠢
㪠⥫  ᫥騩 ᢮   த 믮 . 
᫨  ᯨ᮪ ᢮ ᮢ  (㭮 4.15),  ࠢ -
 ᢮   ஬  ,   ண  -
 ᬮ ᪠  ᫥騩 ࠧ. ᫨ 砫 ᯨ᮪ ᢮ ᮢ
 ,   㭪 4.15(),    ᢮   ஬
499,       ⠫  535  ᯨ᪠. ᫨ ⥬ 
᢮   ஬ 601, ᮤন ᯨ᪠  ᢮  ᮢ  
.    ᯮ    ᯨ᪠ ᢮ -

                                     77

ᮢ  㯥࡫,    ᪠ ᢮ ᮢ  , 
⮬,  砢  ᬮ     ஬ 499,  ᭮ 㦨 
535  601.

              A         B         C
    +------------------------------------------------------------
    |    砥  I       -                -
    |       㯥࡫          -                -
    |                             -                -
    |    ਮ⠭       -                -
    |     ६ 뢠      -                -
    |            ()       -                -
    |            -                -                -
    |            -        ⠥        -
    |            -         㯥࡫      -
    |            -                                 -
    |            -       㯥࡫    ()      -
    |            -                                 -
    |            -       ᬠਢ        -
    |            -       ᪠ ᢮ -     -
    |            -       ᮢ, 饭 -     -
    |            -        I  㯥࡫       -
    |            -                        ()      -
    |            -                -                -
    |      I         -                -
    |    믮       -                -
    |         ⢨            -                -
    |            -                -                -
    |            -       稢 ᬮ,     -
    |            -      砥 㣮     -
    |            -                        ()      -
    |            -                -                -
    |            -                -        砥  I
    |            -                -            㯥࡫
    |            -                -
    |            -                -         I 㦥 ᯮ-
    |            -                -               !
    |            -                -
    |            -                -         砥 㣮
    |            -                -                ()
    |            -                -
    v ६

         㭮 4.16. ७  祭 ᮢ


     ।饬 ࠣ 뢠  砨 ࠡ ⬮. -
 ᬮਬ 砩,   砥     ⥬  
    .  ⬥ ।,     㦨, 
 㦥 祭. ᬮ  । ⠪ 樨, 㤨   -
砩  (  㭪 4.16  4.17).      , A, B 
C,   ,     A (***), 砥  I,  
ਮ⠭ 믮  । ⥬,  ᪮஢ ᪮ -
  .  iget (맢 ⬮

---------------------------------------
(***)      ।饩 ,   "ᮬ"   ",
      饥   ".


                                     78

    |६
    |         +---+---+---+--------------------------------+
    | ()     |   |   |   |                                |
    |         |   |   | I | ------------------------------ |
    |         |   |   |   |                                |
    |         +---+---+---+--------------------------------+
    |         +--------------------------------------------+
    | ()     |                                       |
    |         |       -----------------------------        |
    |         |                                            |
    |         +--------------------------------------------+
    |         +---+---+---+--------------------+---+---+---+
    | ()     |   |   |   |                    |   |   |   |
    |         |   |   |   | ᢮   | J | I | K |
    |         | --|---|---|--------------------|---|---|-- |
    |         +---+---+---+--------------------+---+---+---+
    |         +---+---+---+--------------------+---+---+---+
    | ()     |   |   |   |                    |   |   |   |
    |         |   |   |   | ᢮   | J | I |   |
    |         | --|---|---|--------------------|---|---|   |
    |         +---+---+---+--------------------+---+---+---+
    |         +---+---+---+----------------+---+---+---+---+
    | ()     |   |   |   |    ᢮   |   |   |   |   |
    |         |   |   |   |         | L |   |   |   |
    |         | --|---|---|----------------|---|   |   |   |
    |         +---+---+---+----------------+---+---+---+---+
    v

  㭮 4.17. ७  祭 ᮢ (த)


ialloc)  bread (맢 ⬮ iget)   A 筮  -
⥩   ਮ⠭ ᢮ ࠡ. ।,    A
ਮ⠭,  B ⠥   ,    㦨,
  ᯨ᮪  ᢮  ᮢ   㯥࡫ .  B ᬠਢ
  ᪠ ᢮ ᮢ,  稭    , 饣
訩   ࠢ  ᮬ, 祭  ᮬ  A.  ,
    B 㦨  I  ᪥ ᢮, ⠪   A 
 ਮ⠭,     ,      ᮡ  -
.   B,  ᮧ ᭮, 稢 ᬮ ᪠, -
 㯥࡫ ᢮묨 (।⥫쭮) ᠬ, 砥    
室  業. ,  I ⠥  ᯨ᪥ ஢ ᢮ -
ᮢ    㯥࡫.    A  믮,  稢
祭  I.  ⨬,   C ⥬ ॡ 
 砩 ࠫ  I  ᯨ᪠  㯥࡫.      -
     ,  㦨  ⠭ ⨯ 䠩,   㦥
祭.  ஢  ᫮ , 㦨,    祭,
⠥  㣮.  ९  ᪮४஢  
    ᫥    祭   ᮮ⢥⢨  ⬮ ialloc ᭨
᭮ ७樨, ᪮  ⨯ 䠩 㤥 ᮤঠ    
⮬,   ᯮ짮.
    ஢  ᯨ᪠  ᮢ    㯥࡫  ⥭  ᪠ ࠭
㣨   ७樨. ᫨ 㯥࡫  ஢,  
  㦨,   ,      ᪠, ६ 
६ ਮ⠭ ᢮ 믮  襭 樨 -뢮.
।,  ன  ⠪  ⠥     -
㦨,  ᯨ᮪ .  ⮦ ⠥  ᯨ᮪  ᪠.  
襬 砥,   த㡫  㣠   ࣨ 業-
ࠫ쭮  .  襬,  ७,  ⮩, 

                                     79

ᠭ  ।饬 ࠣ. 室 ࠧ,  ᫨  ,  ᢮
,   ஢ਫ 稥 ஢ ᯨ᪠,     -
ᮢ 㦥  ᯨ᪥ ᢮ ᮢ,  㣮  㤥  
 ᯨ᮪ ଠ樥  ᪠.    ७ 襮ᠭ-
  ⨯. ᬮ  ,      㤠筮 ࠢ  ,
ந⥫쭮 ⥬ ᭨. ⠭ ஢   ᯨ᪠  ᢮-
 ᮢ  㯥࡫ ࠭ ⠪ ७.


        4.7   

      뢠   䠩,   뤥  䠩
⥬  ᪮     ଠ樮  אַ 樨  
  ᢥ 樨. 㯥࡫ 䠩 ⥬  ᮤন  ᨢ,
ᯮ㥬   ࠭ ஢ ᢮ ᪮   䠩 -
⥬. ࢨ᭠ ணࠬ mkfs ("make file system" - ᮧ 䠩 -
) ࣠ ଠ樮   䠩 ⥬   ᯨ᪠   㪠-
⥫ﬨ  ⠪,    ᯨ᪠ 㪠뢠  ᪮ ,  -
஬ ࠭ ᨢ ஢ ᢮ ᪮ ,      ⮢
ᨢ ࠭  ᫥饣   ᯨ᪠.
       㦭 뤥   䠩 ⥬ ( alloc, -
㭮 4.19),  뤥 ᫥騩  ,   ᯨ᪥   㯥-
.  뤥  ,     ७祭   , 
 ᢮. ᫨ 뤥   ᫥ , 騬  
 㯥࡫,  ࠪ   㪠⥫  ,  ஬ ࠭
ᯨ᮪ ᢮ .  ⠥ ,  ᨢ  㯥࡫ -
  ᯨ᪮ ஢   ᫥ ⮣ த ࠡ  ࢮ砫
஬ .  뤥     頥 ᮤন  (-
 ). ᪮  ⥯ ⠥ 祭      
  ࠡ   . ᫨  䠩 ⥬  ᢮ , 뢠騩
 砥 ᮮ饭  訡.
    ᫨  뢠  䠩 让 ꥬ ଠ樨,  ⭮
訢  ⥬   ࠭ ଠ樨,   砥  -

          ᯨ᮪  㯥࡫
         +-----+-----+-----+-----+---------------------+
         | 109 | 106 | 103 | 100 | ------------------- |
         +--+--+-----+-----+-----+---------------------+
      +-----+
      |  109
      |  +-----+-----+-----+-----+---------------+-----+
      +->| 211 | 208 | 205 | 202 | ------------- | 112 |
         +--+--+-----+-----+-----+---------------+-----+
      +-----+
      |  211
      |  +-----+-----+-----+-----+---------------+-----+
      +->| 310 | 307 | 304 | 301 | ------------- | 214 |
         +--+--+-----+-----+-----+---------------+-----+
      +-----+
      |  310
      |  +-----+-----+-----+-----+---------------+-----+
      +->| 409 | 406 | 403 | 400 |               | 313 |
         +--+--+-----+-----+-----+---------------+-----+
            |
            v

     㭮 4.18.  ᮪  ஢  ᢮  ᪮ 
                     㪠⥫ﬨ


                                     80

  ࠧ ⮫쪮   . ணࠬ mkfs ⠥ ࣠ ࢮ-
砫 易 ᯨ᮪ ஢ ᢮  ⠪, ⮡    -
, । 䠩, 뫨 冷   㣮.  ⮬ 蠥-
  ந⥫쭮,  ᪮ ᮪頥 ६ ᪠  ᪥  ६
  ᫥⥫쭮 ⥭ 䠩 ᮬ.  㭪 4.18 
   饬 ଠ, ।塞 ᪮  饭  ᪠.  
ᮦ, । ஢   ᯨ᪥ ᢮  ९⠭ 
裡   묨 饭ﬨ  ᯨ  ஭ ᮢ,   
䠩  㤠 ,  १ 祣   㯠   ᯨ᮪  
   砩 浪.   ।ਭ ⮪ -
    ᯨ᪥.
      ᢮   free -   뤥 .
᫨ ᯨ᮪  㯥࡫  ,   ᢮   -
      ᯨ᮪.  ᫨, , ᯨ᮪ ,  ᢮ 
⠭ 吝 ;  ९뢠   ᯨ᮪   㯥࡫  
     . ⥬   ᢮  砥 
ᯨ᮪ ᢮   㯥࡫.   ⠭ ⢥ -
஬  ᯨ᪥.
     㭪 4.20  ᫥⥫쭮 権 alloc    free  
,     室  ᯨ᮪ ᢮  ᮤঠ  -
.  ᢮  949  砥    ᯨ᮪.  ⥬  
뤥    㤠    ᯨ᪠. ,  뤥 
109    㤠    ᯨ᪠. ᪮ ᯨ᮪ ᢮   -
࡫ ⥯ ,  ᭮  ᯨ᮪,    ᮤন
 109, 饣 ᫥饩   ᯨ᪥  㪠⥫ﬨ.    㭪

    +------------------------------------------------------------+
    |  alloc   /* 뤥  䠩 ⥬ */    |
    | 室 ଠ:   䠩 ⥬                |
    | 室 ଠ:                    |
    | {                                                          |
    |    믮 ( 㯥࡫ ஢)                 |
    |        ਮ⠭ ( ⮣ ,   㯥࡫|
    |         㤥  ஢);                           |
    |    㤠   ᯨ᪠ ᢮   㯥࡫;   |
    |    ᫨ ( ᯨ᪠ 㤠 ᫥ )                  |
    |    {                                                       |
    |        ஢ 㯥࡫;                            |
    |         , ⮫쪮    ᯨ᪠ ᢮- |
    |          ( bread);                              |
    |        ᪮஢  , ࠭騥   - |
    |         ,  㯥࡫;                                   |
    |        ᢮   ( brelse);         |
    |         ஢  㯥࡫;                      |
    |         믮 ᮢ (᫥  - |
    |         ஢  㯥࡫);                             |
    |    }                                                       |
    |       , 㤠  ᯨ᪠ (-   |
    |      getblk);                                          |
    |    㫨 ᮤন ;                             |
    |    㬥 饥 ᫮ ᢮ ;                 |
    |     㯥࡫  "";                    |
    |     ;                                       |
    | }                                                          |
    +------------------------------------------------------------+


           㭮 4.19.  뤥 ᪮ 


                                     81


4.20()     ᯨ᮪  㯥࡫  ᫥騩 吝  
஬ 211.
     祭  ᢮ ᮢ  ᪮   室
 ⮬,   ᯮ 㯥࡫  ⢥ , ࠭饣 㪠⥫ 
᢮  -     ᮢ.  ন ᯨ᮪
஢      㪠⥫ﬨ,  ⠪,    ᢮  
䠩 ⥬   ஬  ᯨ᪠,     -
 ⠪ ᯨ᪠  ᢮ ᮢ.    稭.
1.   ⠭, ᢮    , ஢: ᫨  ⨯
   䠩 饭,  ᢮.   㦤  㣮 堭 -
   ᠭ ᢮ ᮢ.   ,    ।, ᢮
      , ⮫쪮   .    㫮  ࠧ
     ᪮,  뢠饩,    ᢮,  ଠ樥, 砩
   饩 室 . ⥫쭮,  㦤  譥 堭
   䨪樨 ᢮ ,  ⢥   ࠤ樮 ॠ-
    ⥬ ᯮ ᯨ᮪  㪠⥫ﬨ.
2.   ᪮      ᯮ짮  ᯨ-
     㪠⥫ﬨ:  ᪮   ࠧ 訥 ᯨ᪨ -
   ஢ ᢮ .     室饣   ᮢ
   ࠭ ᯨ᪮ ஢ ᢮ ᮢ.
3. 짮⥫  ᪫  室 ᪮ ,  -
   ,  ⮬ 饥 뢠  ࠡ  ᬮ ᪠  -
   ᪠ ᢮ ᮢ   ⠪ ᪨,  ᫨    
      ᪠ ᢮ ᪮ .

          ᯨ᮪  㯥࡫
         +-----+-----+-----+-----+---------------------+
         | 109 | 106 | 103 | 100 | ------------------- |
         +--+--+-----+-----+-----+---------------------+
      +-----+
      |  109
      |  +-----+-----+-----+-----+---------------+-----+
      +->| 211 | 208 | 205 | 202 | ------------- | 112 |
         +-----+-----+-----+-----+---------------+-----+

         () ࢮ砫쭠 䨣

          ᯨ᮪  㯥࡫
         +-----+-----+---------------------------------+
         | 109 | 949 | ------------------------------- |
         +--+--+-----+---------------------------------+
      +-----+
      |  109
      |  +-----+-----+-----+-----+---------------+-----+
      +->| 211 | 208 | 205 | 202 | ------------- | 112 |
         +-----+-----+-----+-----+---------------+-----+
         () ᫥ ᢮   ஬ 949

          ᯨ᮪  㯥࡫
         +-----+-----+-----+-----+---------------------+
         | 109 | 106 | 103 | 100 | ------------------- |
         +--+--+-----+-----+-----+---------------------+
      +-----+
      |  109
      |  +-----+-----+-----+-----+---------------+-----+
      +->| 211 | 208 | 205 | 202 | ------------- | 112 |
         +-----+-----+-----+-----+---------------+-----+
         () ᫥ 祭   ஬ 949

                                     82


          ᯨ᮪  㯥࡫
         +-----+-----+-----+-----+---------------+-----+
         | 211 | 208 | 205 | 202 | ------------- | 112 |
         +--+--+-----+-----+-----+---------------+-----+
      +-----+
      |  211
      |  +-----+-----+-----+-----+---------------+-----+
      +->| 344 | 341 | 338 | 335 | ------------- | 243 |
         +-----+-----+-----+-----+---------------+-----+

         ()   ᯨ᪠  㯥࡫ ᫥
             祭   ஬ 109

    㭮 4.20. 訢  ᢮ ᪮ 


        4.8   

      ⥬ UNIX ন   㣨 ⨯ 䠩:   ᯥ-
   䠩.   ,       뢠    fifo    (᮪饭    
"first-in-first-out" - " 襫 -  襫" - ᪮ 㦨-
   浪 㯫), ⫨砥  筮 䠩 ⥬,  -
ন  ६  : ଠ,  ⠭  ,  
 ⠭ . ஬ ⮣, ଠ ⠥  ⮬ 浪,  -
஬  뫠 ᠭ  ,  ⥬  ᪠  ⪫ 
 浪. ᮡ ࠭ ஬ ଠ樨    ⫨砥  
ᯮᮡ   ࠭  筮 䠩,  ᪫祭 ⮣,   ᯮ-
 ⮫쪮  אַ,   ᢥ, 樨. ⭮  ।⠢-
    㤥   ᫥饩 .
    ᫥  ⨯ 䠩  ⥬ UNIX  ᯥ樠 䠩,  -
 ⭮ ᯥ樠 䠩 ன -뢮   ᯥ樠-
 䠩 ன ᨬ쭮 -뢮.  ⨯   -
ன⢠,    ⮬  ⠪ 䠩  易    ଠ樥.
 ⮣  ᮤন   - 訩  訩  ன-
. 訩  ன⢠ 㪠뢠  ⨯, ਬ, ନ  ,
 訩  ன⢠ - ᫮  ,  騩  ன⢮  
㯯 த ன.  ஡ ᯥ樠 䠩 ன -
ᬠਢ   10.


        4.9 


      ।⠢ ᮡ  ,  ன 뢠 -
 䠩,  ⮬ ᫥ ᯮ ଠ樨 䠩   ᪥.  
 ࠧ :   ᪥,  ன ࠭ ଠ -
,  䠩 室  ࠡ,    ,  ࠭ ଠ-
  ⨢ 䠩.  ialloc  ifree ࠢ 祭 䠩
᪮    ६ 믮 ⥬ 権 creat, mknod, pipe
 unlink (. ᫥ ),   iget  iput ࠢ 뤥
ᮢ     饭   䠩.  bmap ।-
 ⮭宦 ᪮ , ਭ 䠩, ᯮ ।-
⥫쭮  ᬥ饭    砫 䠩.  ⠫  ।⠢
ᮡ 䠩,  ⠭ ᮮ⢥⢨  ⠬  䠩-
  ࠬ ᮢ.  namei ८ࠧ  䠩,  묨
ࠡ  ,  䨪 ᮢ,  묨 ࠡ⠥ . -
,  ࠢ 祭 䠩  ᪮ , ᯮ -
 alloc  free.

                                     83

     , ᬮ७  饩 ,    易
ᯨ᪮, -।   ᨢ,  ⮬ , ࠡ騥 
ᬮ७묨  ࠬ  , 筮 .  
⮣,   ७,  뢠  ⢨  ⬮
 ᮡ,     ஡ ᨭ஭樨 ᬮ७  ⥪.
    ,    ⮫쪮 ⠫쭮 ࠧࠡ⠭   㦨
樥  樨 ⥬.
    襮ᠭ    ࠡ      
짮⥫.   窨 ७ 饩 ⥪ ⥬ (㭮 2.1), -
, ᬮ७   ,  ⭮襭     -
⥬  ࠢ  䠩.    饭 ࠧ 饭 
樮 ⥬, ᯥ稢 㭪樮஢ 짮⥫᪮  -
䥩,   ᠭ 孥  ⥬ ࠢ 䠩,  -
ன 뢠 믮 ᬮ७  ⬮.

8.  ᨨ V ⥬ UNIX ࠧ蠥 ᯮ짮   14 ᨬ  
        ᪠.  namei ᥪ 譨 ᨬ-
     .  㦭 ᤥ  䠩 ⥬   ᮮ⢥-
    ⬠, ⮡ ⠫ ⨬묨   ந쭮 -
    ?
9. ।,  짮⥫    ⥬ UNIX,  祬
         ⠪ ,    ⥯  
    30 ᨬ;   ⥬ ᯥ稢   ᯮᮡ ࠭-
    ᥩ ⠫,   ⠭⭠ 樮 ⥬,   ᪫-
   祭  ⮣,     ⠫   32   16. ᫨
   짮⥫ ᬮ  䠩 ⥬  ⠭⭮  -
     ।,   ந  ६ ࠡ ⬠ namei,  -
      䠩 ?
*10. ᬮਬ ࠡ ⬠ namei  ८ࠧ   ᪠ 
   䨪 .  祭 ᥣ ᬮ  ஢ ᮮ⢥-
   ⢨ ⥪饣 ࠡ祣   ⠫.   㣮  
   㤠  (unlink) ⠫ ?  ࠧ  ।० ⠪ -
    ?  ᫥饩   ୥  ⮩ ஡.
*11. ࠡ⠩  ⠫,  䥪⨢  ᪠  
   䠩    ᯮ짮   ᬮ. ᬮ  ᯮᮡ:
   ஢  n- ॢ.
*12. ࠡ⠩  ᮪饭 ⢠ ᬮ஢ ⠫  -
     䠩, ᯮ   㯮ॡ塞 .
*13.  쭮 砥  䠩 ⥬    ᢮ ᮢ
    ࠬ, 訬, 祬  "" , ᯮ㥬  -
   ⬮ ialloc.  砥,   ⢥ত 뢠  ?
14.  㯥࡫    ᪮    ᮤন ஬ ᯨ᪠ ᢮
      ଠ,     .  ⮬  ᯨ᮪
   ᢮   㯥࡫   ᮤঠ  ஢ ᢮
   ,  祬      ᪮   易 ᯨ᪥
   ᢮ ᪮ .  ᫮ ஢ ᢮   뫮  
   ⨬  ࠭     易 ᯨ᪠ ?













                                     84
