<title>Unix overview CHAP13</title>



     13

         




     ।饩   뫨 ᬮ७ ᨫ쭮易 -
  ⥬   饩 , 騬 ࠬ    騬 㫮,
 ண  뢠  믮. , ,  뢠  -
⥫쭮    楫 ᯥ祭 ᮢ⭮ ᯮ짮 ᮢ ।
 ⠪ ࠧ, ⮡  뫨 ⮭  樮  ।  
᫮  ᯫ樨.  , ਬ, 짮⥫ ᮭ쭮  㦭
  䠩, 室騬   㯭 設,   ࠭  
⮬ ஫  ᮭ쭮 . ᬮ  ,  ⤥ ணࠬ,
⠪   uucp, ন । 䠩    㣨 ⥢ 㭪-
樨,  ᯮ짮  㤥   짮⥫,  ᪮  짮-
⥫      ⮬,    ࠡ⠥  . ஬ ⮣,  , 
ணࠬ,  ⥪⮢ ।ࠬ,  㤠묨 䠩,    -
묨,  ࠡ. 짮⥫  ᯮ ⠭ ஬ 㭪-
権  ⥬  UNIX  ,   ᪫祭    த⢨, 
  祭 設 ࠭. , ਬ, ࠡ  ⥬
㭪権  open   read  䠩  㤠 設   ⫨ 
 ࠡ  䠩, ਭ騬  ⥬.
    ⥪ । ⥬ ।⠢  㭪 13.1.  
,    㭪,  ⮭ 㫥, 騬 
,   ਩ ன. ⢥⢨   蠥  
ᬮ  ,    ᯮ 쭮 䠩 ⥬: 
    ਩  ன⢠   裡  㣨 設,  
ਭ騥  䠩  ᯮ    . ᪠
, 㯭  設,      ᮢ,  믮塞  
㣨 設. ⮩ ᮡ । ⥬ ⫨  ᨫ-
易   ⥬, ᬮ७  ।饩 . -
⢥⢥,  

+-----------------------------+    +-----------------------------+
|       +------------+        |    |       +------------+        |
|       |  |        |    |       |  |        |
|       +-----+------+        |    |       +-----+------+        |
| ----+-------+------+------- |    | ----+-------+------+------- |
| +---+----+ +-------+------+ |    | +---+----+ +-------+------+ |
| |  | | ਩ | |    | |  | | ਩ | |
| |        | |  ன⢠  | |    | |        | |  ன⢠  | |
| +--------+ +--------------+ +-++-+ +--------+ +--------------+ |
+-----------------------------+ ++ +-----------------------------+
                                |
                  +-------------+---------------+
                  |       +------------+        |
                  |       |  |        |
                  |       +-----+------+        |
                  | ----+-------+------+------- |
                  | +---+----+ +-------+------+ |
                  | |  | | ਩ | |
                  | |        | |  ன⢠  | |
                  | +--------+ +--------------+ |
                  +-----------------------------+

    㭮 13.1.  ⥬  । ⥪ன

                                    381


⥬   設 㭪樮 ᨬ  譨 ᫮ ᯫ-
樨 । ।.
    । ⥬,  ᠭ  ,  ࠤ樮  -
  ᫥騥 ⥣ਨ:
  *  ਩  ⥬,  ।⠢騥 ᮡ 㯯 設, ⫨
    મࠦ 魮  易   (筮  㯭)  -
    設. ਩   ᢮ 㧪  業ࠫ -
    ஬   ॠᮢ뢠   饭  樮 ⥬. 
    ਩ ⥬ ⮨  㢥祭 饩 ந⥫쭮  
        ।⠢   뤥    
    樮 । UNIX. ⥬ ᪠  ⤥ ;  -
    稥  㣨  । ⥬, ਩  ⥬  
      ॠ쭮  ⮭,  ᪫祭 砥, 易  -
    ਧ樥 ᮢ  । 쭮 .
  * । ⥬ ⨯ "Newcastle", 騥  ⢫  -
    ⠭樮    㤠 䠩  ⥪ ( 
       "The Newcastle Connection" - . [Brownbridge 82]). 
    䠩  ᯥ䨪 (⠢ ),   㪠  ᪠
    ᮤন ᯥ樠 ᨬ  ⥫  ,  ।-
       䠩 ⥬.  ⮣ ⮤  ।-
     ᥭ    ⥬, ᫥⢨ ⮣   ,
    祬 㣨 ⮤, ᬠਢ  ⮩ ,   .
  * ᮫⭮ "஧" । ⥬,    饭 
    䠩, ᯮ  㣨 設, 筮 㪠  ⠭-
     ⠢ ; ᯮ  䠩   㤠  室  
    易  .  ᪠ 䠩, 㪠   ⠢ -
    , ᥪ 設 ࠭  窠 ஢, ᪮쪮  ⠪
    祪  뫮 ନ஢  ஢ 䠩 ⥬  ᪠.

     饩   ᬮਬ ⥪  ;   ਢ-
 ᢥ    १  ࠧࠡ⮪,   -
樨, 㡫襩  ࠧ 孨᪨ .  ⮬ ।-
,    樨, ⨧樨, ࠢ ⮪, 㦥-
  ࠢ 訡   㫨 ⮪  ࠩ ன-
,  㣨  ᫮,         ᯮ㥬 .
ਬ ᯮ짮 ⥬ 㭪権, ਢ  ᫥饬 ࠧ  
਩   ⥬,  ࠡ    ࠧ      ⥬  ⨯
Newcastle   ᮫⭮ "஧" ⥬,      ;
⮬   ⠫   ᬮਬ  ࠧ,   ࠧ, 饭 -
 ⨯ ⥬, ⠭  ᭮  ᮡ, ⫨  -
   ⠫.


        13.1  

    ⥪ ਩ ⥬   㭪  13.2.    ⠪
䨣樨 ⮨  襭 饩 ந⥫쭮    -
।  믮塞  ᮢ  業ࠫ  ਩묨 -
ࠬ.    ਩ ஢    ᯮ殮  㣨
  ਩  ன, ஬ ,   㦭  裡 
業ࠫ ஬.  ⥬   ன⢠ 室   -
殮  業ࠫ쭮  .  ।,    짮⥫᪨
 ᯮ  ਩     ਩묨  -
ࠬ  ६;   । ,  ॡ뢠
       襭. ਩  ᮤন 祭
ਠ 樮 ⥬, ।祭  ࠡ⪨   -
饭  ⥬, ࠢ 뢠ﬨ, । , ࠡ  -
⥢묨 ⮪   ࠩ஬ ன⢠ 裡  業ࠫ ஬.

                                    382

     樠樨 ⥬  業ࠫ쭮     裡
㦠     ਩ ஢  樮 -
⥬.  믮塞  ਨ  易    ᮬ-⭨,
ਭ騬  業ࠫ쭮    (.  [Birrell 84]);  ,
⥪騩  ਩ , 뢠 ⥬ 㭪,  
㦤  㣠 ᪫⥫쭮 業ࠫ쭮 , ਩ -
 뢠  ᢮ ⭨   㯠  ࠡ  業-
ࠫ  .  -⭨  ᯮ ⥬ 㭪  뫠
१ ⭮  ਩ . ⭮襭  ਩
   ᢮ ⭨ 宦  ⭮襭   ࢥ, ஡
ᬮ७    11: ਩  㯠 ⮬ ᢮-
 ⭨, ন饣 㭪樨 ࠡ  䠩  ⥬.    ⮬
㤠 -ࢥ  ⮫쪮  .  ࠧ 13.4  -
ᬮਬ -ࢥ, 騥 ᪮쪮 ⮢.

    ࠫ               ਩ 
+-----------------------------+    +-----------------------------+
|       +------------+        |    |       +------------+        |
|       |  |        |    |       |  |        |
|       +-----+------+        |    |       +-----+------+        |
| ----+-------+------+------- |    | ----+-------+-------------- |
| +---+----+ +-------+------+ |    | +---+----+                  |
| |  | | ਩ | |    | |  |                  |
| |        | |  ன⢠  | |    | |        |                  |
| +--------+ +--------------+ +-++-+ +--------+                  |
+-----------------------------+ ++ +-----------------------------+
                                |
                  +-------------+---------------+
                  |       +------------+        |
     ਩ |       |  |        |
         |       +-----+------+        |
                  | ----+-------+-------------- |
                  | +---+----+                  |
                  | |  |                  |
                  | |        |                  |
                  | +--------+                  |
                  +-----------------------------+

           㭮 13.2. 䨣 ਩ ⥬


     ਩  뢠 ⥬ 㭪,   -
ࠡ  쭮,      뫠  -⭨.
, ਬ,  楫 祭 ⥫쭮    맢
 쭮 ᯮ 㭪 sbrk. , ᫨ ॡ 㣨  業-
ࠫ쭮  , ਬ, ⮡  䠩,   ଠ
 । 맢 㭪樨 ࠬ  ᫮ 믮  
 ᮮ饭,  뫠  -⭨  (㭮  13.3).  饭
砥  ᥡ ਧ,  ண ᫥,  ⥬ 㭪 믮-
  ᮬ-⭨   , । 㭪樨 ࠬ 
  । 믮  (ਬ, 짮⥫᪨    㯯
  䨪樨),    ࠧ 㭪権 ࠧ. ⠢ 
ᮮ饭 ।⠢ ᮡ  ६    (ਬ,  ⠢
 䠩  , ।祭   㭪樥 write).
    -⭨  㯫 ᮢ  ਩ ; 
祭    ᮮ饭, । ⨯ ⥬ 㭪樨,
ᯮ   ८ࠧ १  ⢥, 뫠 ਩ -
.  ⢥,    १⮢ 믮 ⥬ 㭪樨, 砥 
ᥡ ᮮ饭 

                                    383

ଠ ᮮ饭
+----------------+----------+---------------+--------------------+
| ਧ 맮 |ࠬ |  । |    ⠢    |
| ⥬ 㭪-|⥬ |믮 -|-------    ------|
| 樨            |㭪樨   |          |    ⮪     |
+----------------+----------+---------------+--------------------+

    ⢥
    +------------+-----------+---------+---------------------+
    |  | 饭 |    |                     |
    | 믮 |  訡 | ᨣ |---- ⮪  ---|
    | ⥬  |           |         |                     |
    | 㭪樨    |           |         |                     |
    +------------+-----------+---------+---------------------+

                 㭮 13.3. ଠ ᮮ饭


訡 (᫨   ),  ᨣ  ᨢ  ६ -
, ᮤঠ騩, ਬ, ଠ,  ⠭    䠩.  ਩
 ਮ⠭  祭 ⢥, 稢 , ந -
஢    ।  १ 짮⥫.   奬 ࠡ⪨
饭  樮 ⥬; ⥯ ३    ⠫쭮  -
७ ⤥ 㭪権.
      ⮣, ⮡ ᭨,  ࠧ ࠡ⠥ ਩ ⥬,
ᬮਬ  㭪権: getppid, open, write, fork, exit   signal.  㭪
getppid  쭮 , ᪮  易  묨 ଠ  
⢥, 묨  ਩  業ࠫ .  
਩  ନ ᮮ饭, 饥  ਧ,    ண
᫥,    訢  㭪樥   㭪 getppid,  뫠
 業ࠫ쭮 . -⭨    業ࠫ쭮  
⠥  ᮮ饭    ਩ , ஢뢠 ⨯ ⥬
㭪樨, ᯮ   砥 䨪  ᢮  த⥫.  ⥬  
ନ ⢥  ।  ਩ , 室饬  -
ﭨ    㣮   裡.  ਩  -
砥  ⢥,    ।    ,  맢襬  ⥬  㭪
getppid.  ᫨  ਩  ࠭  (⠪,  䨪-
 -த⥫)  쭮 ,    ਤ 뢠-
  ᢮ ⭨.
    ᫨ ந 饭  ⥬ 㭪樨 open, ਩  -
  뫠  ᢮  ⭨ ᮮ⢥饥 ᮮ饭, ஥ 砥
 䠩  㣨 ࠬ.  砥 ᯥ -⭨  뤥  -
    室  ⠡ 䠩, ⢮   ⠡ 짮⥫-
᪨ ਯ஢ 䠩  ᢮ ࠭⢥  頥  ਯ  䠩
਩ .   ६  㣮   裡 ਩-
   ⢥.    ᯮ殮   , 
࠭  ଠ  뢠 䠩; 頥 㭪樥 open -
ਯ  ।⠢  ᮡ  㪠⥫     ⠡ 짮⥫᪨
ਯ஢ 䠩, ਭ饩 -⭨.    믮
㭪樨   㭪 13.4.
    ᫨ ந 饭  ⥬ 㭪樨 write, ਩ -
 ନ ᮮ饭, 饥  ਧ 㭪樨 write, ਯ
䠩  ꥬ 뢠 . ⥬  ࠭⢠ ਩ -
      裡   -⭨. -⭨
஢뢠 祭 ᮮ饭, ⠥    裡   -
      ᮮ⢥騩 䠩 ( ⢥ 㪠⥫   ண 
  ஬  ⠡ 䠩 ᯮ ᮤঠ騩  ᮮ饭 -
ਯ);  㪠 ⢨ 믮  業ࠫ쭮  .  


                                    384

         ࠫ              ਩ 
+--------------------------------------+   +---------------------+
|                    ⠡           |   |                     |
|                    짮-           |   |                     |
|                    ⥫-           |   |                     |
|                    ᪨              |   |                     |
|                    ਯ-          |   |                     |
| ⠡   ⠡  ஢             |   |                     |
| ᮢ  䠩   䠩   +--------+|   |     +---------+     |
| +-----+   +-----+  +-----+ |-|----------|  |     |
| |     |   |     |  |     | |⭨ ||   |     +---------+     |
| +-----+   +-----+  +-----+ +-+------+|   |                     |
| |    -+-+ |     | ++-   -+---+       |   |                     |
| +-----+ | +-----+ |+-----+ ਯ-  |   |                     |
| |     | +-+-   -+-+|     |  䠩 |   |                     |
| +-----+   +-----+  +-----+           |   |                     |
| |     |   |     |                    |   |                     |
| +-----+   +-----+                    |   |                     |
| |     |   |     |                    |   |                     |
| +-----+   +-----+                    |   |                     |
+--------------------------------------+   +---------------------+

    㭮 13.4. 맮 㭪樨 open  ਩ 


砭  ࠡ  -⭨  । ਩  뫪,
⢥ত ਥ ᮮ饭  ᮤঠ ⢮  ,  ᯥ譮
९ᠭ   䠩.  read 믮 筮; ⭨ ନ-
 ਩   ⢥ ॠ쭮 ⠭    (  砥
⥭   ନ     ⢮  ᥣ ᮢ 
⢮, 㪠  ).  믮  ⮩, ⠪  㣮 -
樨   ॡ ⭠ 뫪 ଠ樮 ᮮ饭 
,  । ꥬ 뫠   ࠧࠬ ⥢ -
⮢.
    ⢥ 㭪樥, ॡ饩 ᥭ   ࠡ   業-
ࠫ쭮 ,  ⥬ 㭪 fork.   ᯮ
  㭪  ,  롨ࠥ   ਩   뫠
ᮮ饭 ᯥ樠쭮  -ࢥ, ନ ᫥    ⮬,  
ᮡࠥ  㯨  㧪 ⥪饣 . ।,  ࢥ
ਭ ,    㭪樨 fork ᮧ   ਩  -
,  뤥   ⠡ ᮢ  ᭮ ࠭⢮. ࠫ-
  㦠  , 맢襣 㭪 fork,   -
਩  ,   ⮫쪮  뤥 ᭮ ࠭⢮, -
஦  ⭨  裡   ਩ ᮬ  뫠-
   ᮮ饭  室 樠樨 稪   
 . -⭨ ( )  ⮬ , 맢-
襣 㭪 fork; ਩   孨᪮ 窨 ७ 㯠
⮬  -ࢥ,      ⮬ , -
襣 㭪 fork. -ࢥ   ᪮ 裡  ⮬ 
襭 㭪樨 fork; ⢥  ࢥ ⮨    -
    㧪  ⮬. - ᨫ쭮 裡  ⠬ ⥬
(਩   ᯮ ⮭) ਩    
-⭨           䨪樨.  
ᠬ   㭪 13.5: 뢭     ⨯
"த⥫-⮬", 㭪஬ -   ࠢࠢ묨 ⭥ࠬ.
       ᯮ 㭪 fork  ਩ ,  -
뫠 ᮮ饭 ᢮ ⭨  ,   ᯮ ᫥ ⮣  
襮ᠭ ᫥⥫쭮 ⢨. ⭨ 롨ࠥ  ਩-


                                    385

     ࠫ             ਩ 
    +----------------------+         +----------------------+
    | +------------------+ |         | +------------------+ |
    | | -த⥫ |-------------|  -ࢥ  | |
    | +---------+--------+ |         | +------------------+ |
    |           |          |         |                      |
    |           |          |         |                      |
    | +---------+--------+ |         | +------------------+ |
    | | ஦ -|-------------| ஦ - | |
    | |               | |         | |              | |
    | +------------------+ |         | +------------------+ |
    +----------------------+         +----------------------+

    㭮 13.5. 믮 㭪樨 fork  業ࠫ쭮 


      室 ਣ⮢  㧪 ࠧ ண
: 뫠 ਩ -த⥫   ⥭   -
ࠧ,    ⢥     㣮   裡 稭 ।
訢 . ⭨ 뢠 ।  ࠧ    ९뢠
   ਩  ⮬.    㧪  ࠧ  稢,  -
-⭨ ᯮ 㭪 fork, ᮧ ᢮ ⮬  ,   -
 祭 稪  ਩ ⮬, ⮡ ᫥ , 
   稭 믮. 祢, 뫮  , ᫨  ⮬
-⭨ 砫 ਩ ⮬  ⢥ த⥫,  -
   襬 砥 ஦    믮 
 㣨 ਩ ,   ⮫쪮  ⮬,  ஬   ᮧ-
.      ᠬ  襭 㭪樨 fork  
㭪 13.6.  ਩  蠥 ᢮ ࠡ,   뫠
ᮮ⢥饥  ᮮ饭 -⭨   ⮦ 蠥.  -
-⭨ 樠⨢ 襭 ࠡ 室  .

                       ࠫ 
    +-------------------------------------------------------+
    |   +------------------+          +-----------------+   |
    |   | ⭨-த⥫ +----------+ ⭨-⮬ |   |
    |   +------------------+          +-----------------+   |
    |             -                            -            |
    +-------------------------------------------------------+
                -                                -
+---------------------------+        +---------------------------+
|             -             |        |             -             |
| +-----------------------+ |        | +----------------------+  |
| | ਩ த⥫ | |        | | ਩ ⮬ |  |
| +-----------------------+ |        | +----------------------+  |
+---------------------------+        +---------------------------+
    ਩                ਩ 

    㭮 13.6. 믮 㭪樨 fork  ਩ 


      ୮,   ୮ ⥬   ॠ-
஢  ᨣ :   蠥  믮  ⥬
㭪樨  ஢ન ᨣ, , ⨢, 稢 ᨣ, ⥫-
 室  ﭨ ਮ⠭  १ 뢠 ࠡ ⥬ 㭪-
樨,  ᫨    ᮣ   ਮ⮬,     ਮ⠭.
᪮ -⭨ 믮 ⥬ 㭪樨   ਩
,   ॠ஢  ᨣ, ᮣ ᢮ ⢨  ᫥-
. ᫨  ୮ ⥬ ᨣ ⠢   -

                                    386

 㭪樨 ਩,  -⭨    ୮  ⥬
᫥  ᥡ ⥬  ࠧ.   ᠬ  ᪠   ⮬ 砥,
  ᨣ  㦤   襭 ᢮ ࠡ   㭪樨
exit: ਩  蠥  뫠 ᮮ⢥饥  ᮮ饭
-⭨, , ࠧ㬥, ⮦ 蠥.
      ਩  뢠 ⥬ 㭪 signal,  -
 ⥪ ଠ   ⠡    뫠  ᮮ饭  ᢮
⭨, ନ   ⮬, ᫥  㪠 ᨣ ਭ  
஢.  -⭨  ࠧ筮, 믮  墠 ᨣ
 ⢨  㬮砭.    ᨣ    䠪-
஢ (㭮 13.7): 㯠  ᨣ  ६ 믮  ᮬ  -
⥬  㭪樨, ᤥ    㭪樨 signal 㪠  ஢-
 ᨣ,   ᨣ  ⮬  ਩     

    +------------------------------------------------------------+
    |  sighandle    /*  ࠡ⪨ ᨣ */    |
    | 室 ଠ:                             |
    | 室 ଠ:                            |
    | {                                                          |
    |    ᫨ (⥪騩   쨬- ⭨     |
    |      ⨯)                                       |
    |    {                                                       |
    |       ᫨ (ᨣ )                           |
    |            ࠢ;                              |
    |       ᫨ (ᨣ 㯨  ६ 믮 ⥬  |
    |        㭪樨)                                            |
    |           ⠢ ᨣ । ᮬ-⭨;      |
    |        ⨢ 砥                                   |
    |           ᫠ ᮮ饭  ᨣ ਩ -|
    |            ;                                             |
    |    }                                                       |
    |     ⨢ 砥       /* ਩  */     |
    |    {                                                       |
    |       /* 㯨  ᨣ  ६ 믮 ⥬  |
    |        * 㭪樨                                     |
    |        */                                                  |
    |       ᫠ ᨣ -⭨;                    |
    |    }                                                       |
    | }                                                          |
    |                                                            |
    |  satellite_end_of_syscall    /* 襭 ⥬- |
    |                                       *  㭪樨, -  |
    |                                       *  ਩|
    |                                       * ᮬ */       |
    | 室 ଠ:                             |
    | 室 ଠ:                            |
    | {                                                          |
    |    ᫨ ( ६ 믮 ⥬ 㭪樨 㯨   |
    |     뢠)                                            |
    |       ᫠ ਩  ᮮ饭  뢠-  |
    |        , ᨣ;                                        |
    |     ⨢ 砥    /* 믮 ⥬ 㭪樨 |
    |                           * 뢠 */                 |
    |       ᫠ ⢥:  䫠, 뢠騩 㯫- |
    |         ᨣ;                                        |
    | }                                                          |
    +------------------------------------------------------------+

       㭮 13.7. ࠡ⪠ ᨣ  ਩ ⥬

                                    387



- 㣮. ३  ᬮ७ ࠧ ⥩.
    ⨬,  ਩  ਮ⠭ ᢮ ࠡ   ६,
  -⭨  ᯮ ⥬ 㭪   . ᫨ ᨣ
  㣮 , -⭨ 㦨  ࠭, 祬 -
਩ .   .
 1. ᫨   ண ᮡ -⭨  室  -
    ﭨ ਮ⠭,  ண  襫   祭 ᨣ,    -
     ⥬ 㭪  , 뫠 १ 믮 -
    ਩   뢠,   ᨣ   祭.
 2.  ᫨    ᤥ  㪠   ஢ ᨣ  ⨯,
    ⭨ த ᫥  믮 ⥬ 㭪樨,  
    室  ﭨ ਮ⠭  longjmp.  ⢥, 뫠 -
    ਩ , ᮮ饭  祭 ᨣ 㤥 ⢮.
 3. ᫨  祭 ᨣ -⭨ 뢠 믮 ⥬
    㭪樨  ( longjmp),  ନ  ⮬ ਩   -
    頥   ᨣ.

    ਩    㯨襬 ⢥ ᢥ  祭 ᨣ-
   砥 㦥 ⠪ ந ࠡ ᨣ । -
室  ⥬ 㭪樨.  ࠧ,    -
୮ ⥬  筮 ᮮ⢥        ୮
⥬:   蠥 ᢮ ࠡ,  室  ० ,  -
    짮⥫᪮ 㭪樨 ࠡ⪨ ᨣ,   ᨣ 
ᯥ譮 蠥 믮 ⥬ 㭪樨.


             ਩              -⭨
    +------------------------------------------------------------
    |    뢠 ⥬ 㭪 read              -
    |   뫠 ᮮ饭  맮 㭪樨           -
    |          -⭨                      -
    |    ਮ⠭  祭              -
    |      ⢥  -⭨       砥 ᮮ饭 
    |                   -                   맮 ⥬ 㭪-
    |                   -                         樨 read
    |                   -                    ⠥   -
    |                   -                          
    |                   -                    ਮ⠭ 
    |                   -                      祭
    |                   -                       樨 
    |                   -                             -
    |                   -                             -
    |                   -                     (짮⥫
    |                   -                     "break")
    |                   -                    室  ﭨ
    |                   -                         ਮ⠭
    |                   -                    ४頥 믮
    |                   -                      ⥬ 㭪樨
    |                   -                     뫠 ⢥ -
    |                   -                     ਩ :
    |                   -                      믮 㭪樨
    |                   -                          ࢠ
    |     室  ﭨ ਮ⠭
    |             ⢥
    v           ࠡ뢠 ᨣ

    㭮 13.8. 뢠  ६ 믮 ⥬ 㭪樨

                                    388


    ।, ਬ,  ਩  뢠 㭪  ⥭
  ନ,  易  業ࠫ ஬,  ਮ⠭ ᢮
ࠡ  ६ 믮 㭪樨 ᮬ-⭨ (㭮 13.8).  ᫨
짮⥫     뢠 (break),   뫠 -
-⭨ ᮮ⢥騩 ᨣ. ᫨ ⭨ 室  ﭨ  -
⠭       ନ 樨 ,   室
 ⮣ ﭨ  ४頥 믮 㭪樨 read.  ᢮  ⢥  
  ਩   ⭨ ᮮ頥  訡   ᨣ,
ᮮ⢥騩 뢠. ਩   ⢥  ,  -
    ᮮ饭    㯫 ᨣ 뢠, ࠢ
ᨣ ᠬ ᥡ. । 室  㭪樨 read ਩  -
 ஢ 㯫 ᨣ, 㦨 ᨣ 뢠,  -
訩  -⭨,  ࠡ뢠   浪. ᫨  -
  祭  ᨣ  뢠 ਩  蠥 ᢮
ࠡ   㭪樨 exit,  㭪   ᥡ    㭨-
⮦ -⭨. ᫨ ਩  墠뢠 ᨣ 
뢠,  뢠 짮⥫ 㭪 ࠡ⪨ ᨣ   -
室    㭪樨 read 頥 짮⥫  訡.  㣮 ஭,
᫨ ⭨ ᯮ    ਩    ⥬  㭪
stat,      㤥  뢠  믮  祭 ᨣ (㭪樨
stat ࠭஢ 室   ਮ⠭, ᪮   ६  -
    ࠭祭).  ⭨   믮 㭪樨   
頥 ਩   ᨣ. ਩   -
 ᨣ ᠬ ᥡ  砥   室  ⥬ 㭪樨.
    ᫨  ᨣ    ਩   ६ 믮 -
⥬ 㭪樨, ਩  㤥 室      ⭮-
⥫쭮  ⮣,  ୥    ᪮ ࠢ  -⭨ 
 ᫥ ३  ﭨ ਮ⠭  । ६. -
਩  뫠 ⭨ ᯥ樠쭮 ᮮ饭, ନ    
 ᨣ.    ஢뢠 ᮮ饭  뫠 ᨣ
⭨,  ॠ ண  祭 ᨣ ᠭ  । ࠣ-
 (਩ 襭 믮 㭪樨      ).
਩       ᫠ ᮮ饭 ⭨ ।⢥,
᪮ ⭨  ᯮ ⥬ 㭪樨   뢠  
  裡.
    ᫨   ਬ  㭪樥 read, ᫥ ⬥,  -
਩     ।⠢  ⮬,    ⭨  -
  ନ   믮 㣨 ⢨. ਩  -
 ⭨ ᮮ饭  ᨣ: ᫨ ⭨ 室  ﭨ ਮ-
⠭  ਮ⮬, ᪠騬 뢠,   室  ⮣
ﭨ  ४頥 믮 ⥬ 㭪樨;  ⨢ 砥  -
 㭪樨   ᯥ譮 襭.
    ᬮਬ, , 砩 㯫 ᨣ  ६,  易 
믮  ⥬  㭪樨.  ᫨  ᨣ    㣮 ,
⭨ 砥    뫠  ᮮ饭    ᨣ  ਩
, ᨬ  ⮣, ᠥ   ᨣ ਩ 
  .  ਩  ஢뢠 ᮮ饭  뫠 ᨣ -
,  ॠ    浪. ᫨ ᨣ   -
਩ ,  믮 ⠭ ⢨,  ਡ 
㣠 ᢮ ⭨.
     ਩  뫠 ᨣ 㣨  ਩  -
ᠬ,      ᮮ饭    맮 㭪樨 kill  뫠  -
-⭨,  ᯮ 뢠 㭪 쭮. ᫨   -
ᮢ,   ।祭 ᨣ,  ⮭宦  㣨 -
਩  , ᨣ  ( ॠ   祭 -
襮ᠭ ࠧ)  ⭨.



                                    389

        13.2   NEWCASTL

     ।饬 ࠧ  ᬮ५ ⨯ ᨫ쭮易 ⥬,  -
ண ࠪୠ 뫪    ਩   -
饭    㭪  ⥬ ࠢ 䠩  㤠 (業ࠫ)
.  ३  ᬮ७ ⥬   ᨫ쭮 , -
   設, ந 饭  䠩, 室騬  -
 設.  , 饩  ᮭ ஢   ࠡ  ⠭-
権,  ਬ,  짮⥫       䠩, ᯮ 
让 設.  ᫥  ࠧ  ᬮਬ ⠪ 䨣樨
⥬,    ⥬ 㭪樨 믮   ⥬,
  ⮬   饭  䠩 (१ 㭪樨 ⥬
ࠢ 䠩), ᯮ  㣨 設.
     ஢ 㤠 䠩   ⥬ ᯮ 
 ᫥  ⥩.   ⥬  ⠢  䠩  
ᯥ樠  ᨬ:  , । ⮬ ᨬ, -
 設, ⠫쭠   - 䠩, 室騩   ⮩  設.
, ਬ, ⠢ 

    "sftig!/fs1/mjb/rje"

  䠩  "/fs1/mjb/rje",  室騩   設 "sftig". 
奬 ஢ 䠩 ᮮ⢥ ᮣ襭, ⠭ ண-
ࠬ uucp ⭮⥫쭮 । 䠩  ⥬ ⨯ UNIX.  㣮
奬 㤠 䠩     ᯥ樠쭮 -
䨪, ਬ:

    /../sftig/fs1/mjb/rje

 "/../" - 䨪, ᢨ⥫騩  ⮬,   䠩  㤠;  
   䠩   㤠 設.   奬 -


        -                      -ࢥ
+-----------------------------+     +----------------------------+
|                      |     |  -                  |
|  -⥪      |     |  ⭨             |
|                   䠩    |     |  (짮-         ⥭ |
|                   +------+  |     |  ⥫᪨      |   |     |
|    +--------------+---   |  |     |  ஢)        |   |     |
|    |              +------+  |     |                  |   |     |
|    |     |      |  |     |    +-------------+   |     |
|    |              +------+  |     |    |                 |     |
|    |         +----+---   |  |     |    |                 |     |
|    |         |    +------+  |     |    |                 |     |
|    |         |    |      |  |     |    |                 |     |
|    |         |    +------+  |     |    |                 |     |
|    |         +-----+        |     |    |                 |     |
+----+---------------+--------+     +----+-----------------+-----+
     |               | 㤠         |                 |
+----+---------------+--------+     +----+-----------------+-----+
|    |              ⥢   |     |    |             ⥢   |
|               䥩 |     |              䥩 |
|                    |        |     |                      |     |
+--------------------+--------+     +----------------------+-----+
                     |                                 |
                     +-------------------------------------+

    㭮 13.9. 㫨஢ ᮢ  䠩 ࢥ ()

                                    390



 ਢ ᨭ⠪  䠩  ⥬ UNIX, ⮬  ⫨稥
 ࢮ 奬  짮⥫᪨ ணࠬ   室  ਭ-
ࠢ    ᯮ짮 ,    (. [Pike
85]).
     ⠢  ࠧ  ⨬  ᬮ७    ⥬,
ᯮ饩   ⨯ Newcastle,  ன    ᯮ-
 㤠 䠩;  㭪    ணࠬ  
⠭⭮  -⥪,  믮騥   砥 ஫ ⥬ -
䥩.  ணࠬ     䠩,  -
 ᠭ ᯮᮡ ஢ ᮤঠ ਧ 㤠  䠩-
.    ⮬ ⮨ 㯫   浪,  ஬ -
 ணࠬ   ᨭ⠪᪨ ࠧ஬    䠩.  
㭪  13.9 ,  ࠧ 㫨   䠩 -
. ᫨ 䠩 ,  쭮 ⥬ ࠡ뢠   -
 ᯮᮡ. ᬮਬ  砩:

    open("/../sftig/fs1/mjb/rje/file",O_RDONLY);

ணࠬ open  -⥪     ⠢-
    䠩    㧭,    䠩 ᫥ ᪠  㤠 設
"sftig". ⮡  ଠ  ⮬, 뫠  ࠭     -
 設, ணࠬ  ᯥ樠 ,  ன -
  䠪,   砥 ⥫쭮 ⢥ ⠭    䠩-
 ࢥ஬, ࠡ騬  㤠 設.   㫨 ᢮
   ⠭樮 ࠡ, 㤠 ࢥ ⢥ত -
,   砥 室     짮⥫᪮  㯯-
  䨪樨  ᮧ ⭨,   㤥  㯠
  -.
    ⮡ 믮  , ⭨    㤠 -
   ࠢ 㯠  䠩,   . 㣨 ᫮, 짮⥫
"mjb"     㤠,    䠩  ࠢ -
㯠.  ᮦ,  ᪫祭  ⮣,   䨪樨 -
  "mjb"    ᮢ   䨪樨 㣮  㤠
設.  ࠧ, ࠬ ⥬  ࠡ     設
᫥  ᫥  祭  짮⥫  䨪樨,
㭨쭮    ᥩ ,    㫨஢   ⥢
㦨 믮 ८ࠧ . ᫨   㤥 ᤥ, -
-⭨ 㤥   㤠 設 ࠢ 㣮 .
      ᮬ  祭  ⭮襭 ࠡ    㤠-
묨 䠩 ࠢ 㯥௮짮⥫.   ஭, -㯥௮짮-
⥫        ࠢ  ⭮襭 㤠 ⥬, ⮡ 
  㦤 ।⢠  㤠 ⥬.   㣮  ஭,
    ணࠬ,  ᫨     ।⠢ ࠢ 㯥௮짮⥫,
  ᬮ ࠡ. ਬ஬ ⠪ ணࠬ  ணࠬ mkdir
(.  7), ᮧ  ⠫.  ⥬    ࠧ訫  
  ᮧ  ⠫, ᪮  㤠 ࠢ 㯥௮짮-
⥫  . ஡ ᮧ 㤠  ⠫  㦨  쥧
᭮    ᬮ  ⥬ 㭪樨 mkdir  ஭ ७ 
⥩  ⮬᪮  ⠭    室  짮⥫
痢.      , 祭 setuid-ணࠬ (  ⭮ 
ணࠬ mkdir) ࠢ 㯥௮짮⥫  ⭮襭  㤠 䠩  
  ⠥  饩 ஡, ॡ饩 ᢮ 襭. ,  -
訬 襭 ⮩ ஡ 뫮  ⠭  䠩 ⥫
ࠪ⨪, 뢠     ஭ 㤠  㯥௮짮-
⥫;  ᮦ,  ॡ  ᥭ    ᪮-
   (    )  த  ᫨誮 让
ᯮ冷   ⥬.

                                    391

    ᫨ ணࠬ open 蠥 ᯥ譮, 쭠 ⥪  ⠢-
  ⮬ ᮮ⢥ ⬥  㯭  짮⥫ ,
ᮤঠ饩   ⥢ 㧫, 䨪 -⭨, ਯ
䠩     ଠ.    ணࠬ  read  
write  ⠭, 室  ਯ,   䠩 㤠,  
砥 ⥫쭮 ⢥  뫠  ⭨  ᮮ饭.  -
    ᢮  ⭨     饭  ⥬
㭪, 㦤騬  㣠 㤠 設. ᫨  頥  
 䠩, ᯮ    ⮩  㤠 設,  
  ⭨,   ᫨ 䠩 ᯮ  ࠧ 設, ᯮ
㦥  ⭨:     設.  ⭨ ᯮ   
⮬ 砥,   䠩  㤠 設   . -
  ⥬ 㭪 १ ⭨,  ନ ᮮ饭, -
饥  ᥡ  㭪樨,   ᪠    室  ଠ,
 ⮩,  室   ᮮ饭  ⥬  ਩-
묨 ࠬ.
    堭  믮  権  ⥪騬 ⠫  ᫮. 
 롨ࠥ  ⢥ ⥪饣 㤠 ⠫,  筠  -
ணࠬ 뫠 ᮮ⢥饥 ᮮ饭 ⭨,   ⥪-
騩  ⠫,    ⮬  ணࠬ ,  ⠫ 㤠. 
 ,    ᪠ 稭  ᨬ, ⫨筮   -
    (/),  ணࠬ  뫠    㤠 設, 
-⭨ ப뢠 , 稭  ⥪饣 ⠫. ᫨  -
騩 ⠫ - , ணࠬ  ।   ᪠ 
쭮  ⥬. ⥬ 㭪 chroot  ⭮襭 㤠 ⠫
믮 宦,   ⮬  믮      쭮  ⥬
室  祭;  ண  ,   ⠢  
 , ᪮ ⮫쪮 ⥪ 䨪  믮.
      뢠 㭪 fork, ᮮ⢥ 筠  -
ணࠬ  뫠  ᮮ饭  ⭨.  -⭨ 믮
 ⢫  뫠 䨪 ᢮ ⮬  -த-
. - ᪠ ⥬ 㭪 fork,  । ࠢ-
  ஦  ⮬;  ⮬    㤠 -
⮬-⭨,  ண ࠭ 筠 ணࠬ. 
ࠪ⮢ 㭪樨 fork 砥 ᠬ-⭨ ஫   묨
䠩  ⥪騬 ⠫.  , ࠡ騩  㤠묨 䠩-
, 蠥 (뢠 㭪 exit), ணࠬ 뫠 ᮮ饭 ᥬ
  㤠  ⭨,  ⮡   祭 ᮮ饭 த  
ᠬ. ⤥  ॠ樨 ⥬ 㭪権 exec  exit ࠣ-
  ࠦ.
    २⢮ 裡 ⨯ Newcastle ⮨  ⮬,  饭  
  㤠  䠩  ⠭ "஧" (  짮⥫),
 ⮬   ⥬     㦭.  ,  
ࠧࠡ⪥    ⪮. ० ᥣ,   ॠ樨 -
 ᭨ ந⥫쭮 ⥬.  裡  ᯮ짮 ७
-⥪ ࠧ ᯮ㥬  ᮬ  㢥稢, -
 ᫨   頥  㤠 䠩; ⥪ 㡫 㭪-
樨     ॡ  ᥡ    . 祭 ࠧ -
ᮢ ਢ  㤫 த⥫쭮 ਮ ᪠     -
   ७   , ᮧ ᫮   -
⮩ 㧪  窨 .    ᯮ 
- 㢥祭 த⥫쭮  饭  ,   -
  ஧  ࠡ⪥ 㤠 ᮢ,   뫪  
 㢥稢. ⥫쭠 ࠡ⪠ 㤠 ᮢ  짮-
⥫᪮ ஢ 㢥稢 ⢮ ४祭 ⥪,  権  
㧪  窥 ᮢ. ,  ⮣, ⮡   㤠-
  䠩,  ணࠬ   ४஢  ᯮ짮 
⥪;  ணࠬ  ⠢ ꥪ 㫨  ⮣  ࠡ-
  㤠묨 䠩  ᬮ.   ⪨   -

                                    392

, 뢠  ᫥饬 ࠧ.


        13.3 ""   


    ନ "஧筮 ।" 砥,  짮⥫, ࠡ騥
  設,    䠩, 室騬  㣮 設, 
ᮧ ⮣,  ⥬ ᠬ  ᥪ 設 ࠭,  ⮬,
   ᢮ 設   室   䠩 ⥬  㣮 -
ᥪ 窨 ஢. ,      䠩,
室騬  㤠 設, 宦    䠩:  ⫨-
⥫  ᨬ      .  䨣樨,   㭪
13.10, ⠫ "/usr/src", ਭ騩 設 B, "஢"    ⠫
"/usr/src",  ਭ騩 設 A.  䨣 ।⠢ 㤮-
  ⮬ 砥, ᫨  ࠧ ⥬ । ᯮ짮   
   室  ⥬, ࠤ樮 室騩  ⠫ "/usr/src".
짮⥫, ࠡ騥  設 A,    䠩, ᯮ-
  設 B, ᯮ ਢ ᨭ⠪ ᠭ  䠩 (-
: "/usr/src/cmd/login.c"),   㦥 ᠬ 蠥 ,    䠩
㤠   . 짮⥫, ࠡ騥  設 B,  -
   ᢮  䠩 ( ॢ  ⮬,   ⨬  䠩 -
   짮⥫ 設 A), ,  ᢮ ।,   -
  䠩, 室騬  設 A. 筮,   㣨 ਠ, 
⭮, ⠪,    㤠 ⥬     ୥  -
쭮  ⥬,  祬 짮⥫    ᥬ 䠩
  ⥬.


            設 A                          設 B
+-----------------------------+    +-----------------------------+
|               /             |    |              /              |
|               |             |    |              |              |
|      +--------+--------+    |    |  +-----------+-----------+  |
|      |                 |    |    |  |           |           |  |
|     bin               usr   |    | usr         bin         etc |
|      |                 |    |    |  |                          |
| +----+----+       +----+--+ |    |  +-------+                  |
| |         |       |       | |    |  |       |                  |
|login    mail     bin     src| +--->src     bin                 |
|                   |       | | |  |  |                          |
|               +---+---+   | | |  |  +------+-----+             |
|               |       |   | | |  |  |      |     |             |
|              troff   vi   | | |  | lib    cmd   uts            |
|                           | | |  |         |                   |
|                           | | |  |     +---+---+               |
|                           | | |  |     |       |               |
|                           | | |  |  login.c   mail.c           |
+---------------------------|-+ |  +-----------------------------+
                            +---+

    㭮 13.10.  ⥬ ᫥ 㤠 ஢


    稥 室⢠  ஢  䠩 ⥬   -
⨥  㯠   㤠 䠩 ⥬ 㦨   樨
㭪樨 mount ਬ⥫쭮  㤠 䠩 ⥬.     砥
 砥  ᢮ ᯮ殮 ⠡ ஢ ७ ଠ.
믮  㭪 mount,  ࣠ ⥢   㤠 設 

                                    393

࠭  ⠡ ஢ ଠ, ࠪਧ  .
    ᭠ ஡ 易   ⥩,  "..". ᫨  -
    ⥪騬 ⠫  㤠 䠩 ⥬, ᫥饥 -
짮   ᨬ ".." ᪮॥ ୥    䠩
⥬, 祬    䠩, ᯮ  ⥪饣 -
.    㭪 13.10, ⬥⨬,   , ਭ-
騩  設  A,  ࠢ  ।⥫쭮    ⢥  ⥪饣   ⠫
"/usr/src/cmd", ᯮ  㤠 䠩 ⥬, ᯮ 

    cd ../../..

⥪騬  ⠫ ⠭ ୥ ⠫, ਭ騩 設 A,   -
設 B.  namei, ࠡ騩   㤠 ⥬, 稢  ᫥-
⥫쭮 ᨬ "..", ஢,   뢠騩  -
⮬  -,   砥 ⥫쭮 ⢥ ⠭, ࠪ-
   ⥪騩 ࠡ稩 ⠫  ⢥   㤠  䠩
⥬.
        㤠 設 ਭ    : 맮 㤠
楤  맮 㤠 ⥬ 㭪樨.  ࢮ ଥ   -
楤  ,       ᠬ, ஢, 㪠뢠   
㤠 䠩,  ᫨  ⠪, 뫠  㤠 設     -
 㪠 樨.  奬 ⢥ ࠧ 뢠 
ࠪ  প 䠩 ⥬ ࠧ ⨯, ᠭ 
⥫쭮      5.  ࠧ, 饭  㤠 䠩
 樨஢ 뫪   ᪮쪨 ᮮ饭, ⢮  -
 । ⢮ ࠧ㬥 権  䠩,  ᮮ⢥-
騬 㢥祭 ६ ⢥    ⮬ ਭ⮣   -
  .    㤠 権 砥  ᥡ,  ࠩ
, ⢨  ஢ ,  뫮  ..  楫  -
襭⢮   । ࠧ ⨬樮 襭, -
  ꥤ ᪮쪨 権    (ᮮ饭)    -
ਧ樥    (. [Sandberg 85]).


       ࢥ                    (/)
+--------------------+  +----------------------------------------+
| ⠡            |  | ⠡   ⠡  ⠡             |
| ᮢ +-------+ |  | ᮢ  䠩   짮-             |
| +-----+  |⭨|-|  | +-----+   +-----+  ⥫-             |
| |     |  +-+-----+ |- | |     |   |     |  ᪨                |
| +-----+    |       |  - +-----+   +-----+  ਯ-   +-------+|
| |     |    |     +------+-   -+-+ |     |  ஢   +--+||
| +-----+    |     | |  | +-----+ | +-----+  䠩   |  +-------+|
| |     |    |     | |  | |     | +-+-   -++ +-----+ |           |
| +-----+    |     | |  | +-----+   +-----+| |     | |           |
| |     |    |     | |  | |     |   |     || +-----+ |ਯ |
| +-----+    |     | |  | +-----+   +-----++-+-   -+-+䠩      |
| |   --+----+-----+ |  | |     |   |     |  +-----+             |
| +-----+            |  | +-----+   +-----+  |     |             |
|                    |  |                    +-----+             |
+--------------------+  +----------------------------------------+

             㭮 13.11. ⨥ 㤠 䠩

    ᬮਬ     ,          뢠     㤠     䠩
"/usr/src/cmd/login.c",  "src" - 窠 ஢.  믮  ᨭ⠪-
᪨ ࠧ  䠩 ( 奬 namei-iget),  㦨,  䠩
㤠,   뫠  設,   室,   祭 -
஢ . 稢  ⢥, 쭮  ᮧ   -

                                    394

   , ᯮ  㤠 䠩. ⥬  ந-
 ஢  室 ࠢ 㯠  䠩 (  ⥭,  -
),  ᫠    㤠 設   ᮮ饭. 믮 ⬠
open த   ᮮ⢥⢨  , ਢ    5,  
뫪  ᮮ饭    㤠  設   室,  
砭 ⬠  ᢮ .      ࠬ
   襭 ⬠ open   㭪 13.11.
    ᫨   뢠 ⥬ 㭪 read,    -
 , 뫠   ஢ 㤠  ,  
 ⥭ ,     , 뫠   -
  㤠     ᢮  .  奬
ᮮ⢥ ᥬ⨪ 饣 ୮ ,   -
짮  (᪮쪮 饭   ⥬  㭪)  ᭨
ந⥫쭮  ᥩ  ⥬. , ⮡ 㬥 ⮪ ᮮ饭 
,     ꥤ ᪮쪮 権.  ਬ  㭪-
 read   ᫠ ࢥ  騩     "⥭",    
ࢥ   믮 ᠬ ਭ 襭  墠  ᢮ -
. 饭 ⥢ 䨪    ⥬ ᯮ짮 㤠-
  ஢ ( 祬  㦥 ਫ ),   ⮬ 㦭 
 ⮬, ⮡ ⥬ 㭪樨 ࠡ  䠩,  ᯮ騥    ,
믮﫨 騬 ࠧ.
      ன  ଥ  裡  㤠 設 (맮 㤠 ⥬
㭪樨) 쭮  㦨,  ⥬ 㭪   ⭮襭
  㤠 䠩,  뫠 㪠   맮 ࠬ  㤠
⥬,  ᯮ 㭪  頥 १  .  設
  砥 १ 믮 㭪樨  室  ﭨ 맮-
. 設⢮ ⥬ 㭪権      믮    ᯮ짮
⮫쪮  ⥢   祭 ⢥ १ 筮 ਥ-
  ६,    ⠪  뢠   㭪樨. , ਬ, 
祭  ᨣ  ᮧ   䠩    "core"
(  7).  ⮣ 䠩  易  ⭮ ⥬ 㭪樥,
 蠥 믮 ᪮쪨 権, ⠪  ᮧ  䠩,  -
ઠ ࠢ 㯠  믮 鸞 権 .
     砥  ⥬ 㭪樥 open   ᯮ 㭪樨, 뫠-
  㤠 設, 砥  ᥡ   䠩, ⠢ -
 ᪫祭    ᪠, ⫨ 㤠 䠩,  ⠪-
  ࠧ  䫠.    ᬮ७  ࠭  ਬ    ⨥  䠩
"/usr/src/cmd/login.c"  뫠  㤠 設   "cmd/login.c".
饭  ⠪ 砥  ᥡ ⥫ , ⠪  짮-
⥫᪨  㯯  䨪樨, 室  ஢ન ࠢ  -
㯠   䠩  㤠 設. ᫨  㤠 設 㯠 ⢥,
ᢨ⥫騩  ᯥ譮 믮 㭪樨 open, 쭮   롨-
ࠥ  ᢮      쭮 設  砥   
㤠 䠩, ࠭ ଠ  㤠 設   㤠  -
        浪 뤥    ⠡ 䠩. 
ࠢ  ॠ ᮬ  㤠 設 , ਭ騩  -
쭮  設,  ଠ,  騬 䨣 , -
  楫 ᮢ  䨣樥, ᯮ㥬   맮  㤠
楤  (㭮  13.11).  ᫨ 뢠 ᮬ 㭪 頥 
㤠 䠩   ਯ, 쭮  㧭     (-
쭮)    ⮬,  䠩 㤠, 㫨 , 騩  ᥡ
뢠 㭪,  뫠   㤠 設.   ᮤন
㪠⥫  㤠 ,  ஬ -⭨ ᬮ  -
஢ ᠬ 㤠 䠩.
    稢 १ 믮  ⥬ 㭪樨,    
ࠡ⪨  ਡ  㣠 ᯥ樠쭮 ணࠬ ( 襭 ன
  ࠡ  㭪樥),   ᥣ 쭠 ࠡ⪠  १-
⮢,  ਬ塞   ୮ ⥬, 室  ⥬  -
쪨 ࠬ. ᫥⢨ ⮣    ᥬ⨪  -

                                    395

⥬  ⬮, ࠢ  ᯥ祭 প 믮 㤠-
 ⥬ 㭪権. ,  ⮬   㫨  ⮪
ᮮ饭, ᯥ稢騩 쭮 ६ ॠ樨 ⥬    㯠騥
.


        13.4     

    ᯮ짮  ।  ᮢ (ᮢ-⭨)  "஧-
" । ⥬ 砥 ᫥  㤠묨 䠩, 
 ⮬ ⠡ ᮢ 㤠 ⥬ ॣ㦠  ᠬ--
, 騬   ६.  㣨 奬  ࠡ⪨
㤠  ᮢ ᯮ ᯥ樠 -ࢥ (. [Sandberg
85]  [Cole 85]).   ⥬  ᯮ  ஬  (㫮)  -
ᮢ-ࢥ஢, ६  ६ 砥   ࠡ⪨ 㯠 㤠-
 ᮢ. ᫥ ࠡ⪨  -ࢥ 頥   
室    ﭨ  ⮢   믮 ࠡ⪨ 㣨 ᮢ.
ࢥ  ࠭ 짮⥫᪨ ⥪    饭ﬨ,  
    ࠡ뢠    ࠧ ᪮쪨 ᮢ. ⥫쭮,
 㯠饥  - ᮮ饭    ᥡ  -
ଠ   ।  믮,  :  䨪樨 짮⥫,
⥪騩 ⠫, ᨣ  .. -⭨      -
 ᢮    ६ 믮 ⥬ 㭪樨.
      뢠 㤠 䠩,  㤠 ⥬ 砥
  ᫥ 뫮  䠩. 쭠 設 ᯮ ⠡楩
짮⥫᪨  ਯ஢  䠩, ⠡楩 䠩  ⠡楩 ᮢ 
 ஬ ᥩ, 祬     ⠡  ᮢ  
㤠  設  㤠 .   ,  ⥬ 㭪
(ਬ, read) ᯮ ਯ 䠩,  뫠 ᮮ饭,  㪠-
뢠饥   ࠭ 祭 㤠 ,  । 易  -
ᮬ ଠ:   䨪樨  짮⥫,  ᨬ쭮-⨬
ࠧ  䠩    .. ᫨ 㤠 設   ᢮ ᯮ殮 -
-ࢥ, ⢨  ⮬ ਭ , ᠭ ࠭, -
   ⮬  ࢥ஬ ⠭ ⮫쪮  ६  믮-
 ⥬ 㭪樨.
    ᫨    ᮢ-⭨ ᯮ짮 㣠 ࢥ஢, -
ࠢ ⮪ , ᨣ  㤠묨  ன⢠    ᫮-
.  㯠騥  讬 ⢥   㤠 設  -
⢨ 筮 ᫠ ࢥ஢   ࠨ    ।.  
⮣  㦥 ⮪  ᮪ ஢, 祬 ,  ᯮ 
᭮ .  , ᯮ饩 ⭨,  㣮  ஭,  ७-
饭 ᠬ ᪫砥,     ࠡ뢠 ᨭ-
஭.       , 饣 ࠡ⪨.
    ࠡ⪠  ᨣ,  뢠  믮 ⥬ 㭪樨,  -
짮 ࢥ஢ ⠪ ᫮, ᪮ 㤠 設 室-
  ⮬ ᪠ ᮮ⢥騩 ࢥ, 㦨騩 믮 㭪樨.
 ᪫砥   ⠪ ,   裡     -
஢    믮 ⥬ 㭪樨 室  ﭨ 
ࠡ⪨. ᫮   ७樨 ᪫뢠  ⮣, 
ࢥ 頥 १ 믮 ⥬ 㭪樨 뢠饬 -
  ⢥ ࢥ 砥  ᥡ 뫪 १  ᮮ⢥饣 ᨣ-
쭮 ᮮ饭.  ᮮ饭     祭  ⠪  ࠧ,
⮡  㤠 ⥬  ᯮ    砥 室 -
 ࠡ ᮢ-ࢥ஢.  ᯮ짮 ⭨  , -
 㦨 믮  ,   ⮬-
,      砥  㯫 ᨣ ஢ઠ ⮣, 祭  ࠡ⪠
  ,  ⠢ ᮡ 㤠.
    , ᫨ 뢠 ⮬ ⥬  㭪  ⠢  ࢥ
ਮ⠭   । ६ (ਬ,  ⥭   㤠-

                                    396

 ନ), ࢥ    ࠡ 㣨  ᮢ,  ⮡
᢮  ⥬ ᠬ ࢥ . ᫨  㤠 ன⢠ 
ࠧ ᪮쪮 ᮢ  ᫨   ⮬  ⢮  ࢥ஢  ࠭祭
ᢥ,    ⨬ 㧪 .  ᯮ짮 ⭨
⮣   ந室, ᪮ ⭨ 뤥  -.
  ஡, 易  ᯮ짮 ࢥ஢  㤠 ன-
, 㤥 ᬮ७  ࠦ 13.14.
    ᬮ  २⢠,   ।⠢  ᯮ짮  -
ᮢ-⭨, ॡ  ᢮  ⠡ ᮢ  ࠪ⨪
⠭ ⮫쪮 ன,   設⢥ 砥  ࠡ⪨ 㤠-
 ᮢ -⠪ ਡ  㣠 ᮢ-ࢥ஢.


짮⥫   +------------------------------+
     |         | ⥪ ⥬ 㭪権 |
     |         +------------------------------+
     |         | ஢ 裡 ⨯ Newcastle |
     v         +------------------------------+
     ^         +------------------------------+
     |         | ணࠬ ࠡ⪨ - |
     |         | 饭  ⥬ 㭪樨    |
     |         +------------------------------+    + ਩
     |         | ணࠬ ⢨ <----+ ⥬,
     |         | 㤠 䠩 ⥬  |    | 맮 㤠-
     |         +------------------------------+    +  ⥬
     |         | ⥬ ࠢ 䠩<------맮 㤠-
           +------------------------------+       楤

    㭮 13.12.  楯㠫쭠 奬 ⢨  㤠-
                    묨 䠩  ஢ 



        13.5 

          뫨 ᬮ७  奬 ࠡ  ᯮ묨
 㤠 設 䠩, ࠪ騥 㤠 䠩 ⥬  -
७ 쭮. ⥪ ࠧ  ⨬  奬    
㭪  13.12.     ᢮ । ⫨   -
⥬, ᠭ  ।饩 , ⥬,       ᯮ
䨧  ᮢ⭮. ⥬  ਩묨 ࠬ ⮨ 
ᨫ쭮易  ஢, ᮢ⭮ ᯮ 䠩 
業ࠫ쭮  .   ⨯ Newcastle ᯥ稢  ("஧-
")   㤠 䠩,   ।⢠  樮  -
⥬,     ᯮ짮 ᯥ樠쭮 -⥪.  ⮩ 稭
 ணࠬ, ।騥 ᯮ짮   ⨯,    
४஢,   饬-  쥧 ⪮ ⮩ 奬.
 䠩 砥   ᯥ樠쭮 ᫥⥫쭮 ᨬ-
,  뢠  設,   ன ᯮ 䠩,    
 䠪஬, ࠭稢騬 쭮 ணࠬ.
     "஧" । ⥬  㯠    㤠  䠩
ᯮ 䨪 ⥬ 㭪樨 mount.   쭮 -
 ᮤঠ ⬥  ⮬,   ⭮  㤠 䠩,  쭮
 뫠  㤠 ⥬ ᮮ饭, 뢠饥 訢 -
⥬  㭪,  ࠬ  㤠 .   "஧筮" -
। ⥬ ন   ଠ:   ଥ  맮  㤠
楤  (  㤠  設  뫠 ᮮ饭, ᮤঠ饥 祭
権, 易  ᮬ)   ଥ 맮 㤠 ⥬ 㭪樨
(ᮮ饭 뢠 訢 㭪).   ⥫쭮    

                                    397

ᬮ७  , 騥 ⭮襭  ࠡ⪥ ⠭樮 ᮢ 
 ᮢ-⭨  ࢥ஢.


        13.6 

 *1.  ॠ ⥬ 㭪樨 exit    ⥬    ਩묨
     ࠬ.  祬 ࠧ  ⨬ 砥  ⥬,   -
     蠥 ᢮ ࠡ  祭 墠祭 ᨣ ?  -
       ᫥ ࠭  ᮤন  ?
  2.        ஢ ᨣ ⨯ SIGKILL; ᭨, 
     ந室  ਩ ⥬,   砥 ⠪ ᨣ.
 *3.  ॠ ⥬ 㭪樨 exec    ⥬    ਩묨
     ࠬ.
 *4.  ࠧ 業ࠫ쭮  ᫥ ந ।
     ᮢ   ਩묨 ࠬ  ⥬, ⮡ ᡠ஢
      㧪 ?
 *5.  ந  ⮬ 砥, ᫨  ਩   -
      筮   ࠧ饭  㦥   ᮢ?
     ࠧ  ந 㧪  窠 ᮢ  ?
  6. ᬮਬ ⥬,  ன    㤠  䠩  ࢥ
     뫠    砥  㦥   䠩 ᯥ樠쭮 䨪.
       뢠 㭪
               execl("/../sftig/bin/sh","sh",0);
     ᯮ塞  室  㤠 設,   믮
      쭮 ⥬. ᭨,  ࠧ 㤠   ७-
        ⥬.
  7. ᫨  㦭    ⥬   -
       Newcastle  設,    ⮬  ᥣ நନ஢
     㫨 -⥪ ?
 *8.  ६ 믮 㭪樨 exec   ࠥ  ᭮  ࠭⢮
     ,        ⠡,  ᯮ㥬  ⨯
     Newcastle  ᫥  뫪  㤠 䠩. ᫥ 믮
     㭪樨   ࠭  饭  ⨬ 䠩 
       ਯࠬ.  ॠ ⮣ .
 *9.    ࠧ 13.2, 맮 ⥬ 㭪樨 exit  ⥬ 
      ⨯ Newcastle ਢ  뫪  ᮮ饭  -⭨,
     ⠢饣  ᫥   ᢮ ࠡ.    ஢
      ணࠬ.  ந室,    -
     砥 ᨣ, 㦤騩   ᢮ ࠡ  ०  ?
*10.  ࠧ  ⥬   ⨯ Newcastle,   㤠  䠩
           ᯥ樠쭮 䨪, 짮-
     ⥫ , 㪠  ⢥   䠩 ".." (த⥫᪨
     ⠫),  㤠  ஢ ?
 11.   7  ⭮  ⮬,  ࠧ ᨣ 㦤  
     뢠   ᮤন   ⥪騩 ⠫.   ந-
       ⮬ 砥, ᫨ ⥪騬  ⠫  㤠 䠩
     ⥬ ?  ⢥    ⮬ 砥, ᫨  ⥬  ᯮ-
       ⨯ Newcastle ?
*12.   ᫥⢨   ᮢ   㤠  ⥬
      ᮢ-⭨  ࢥ஢ ?
*13. 㬠  ⥬,   "஧筮"  ।  ⥬  ᫥
     ॠ    link,  ࠬࠬ ண    
     㤠 䠩,  ⠪  exec, 易   믮  -
     쪨  ७ 権 ⥭. ᬮ   裡: 맮
     㤠 楤  맮 㤠 ⥬ 㭪樨.
*14.  饭  ன -ࢥ    ३    ﭨ
     ਮ⠭,  ண  㤥 뢥 ࠩ஬ ன⢠. -
     ,  ᫨  ᫮ ࢥ஢ ࠭祭, ⥬  ᬮ  㤮-

                                    398

     ⢮  쭮 設. ਤ㬠  奬,  -
     ன   襭 -뢮, 易  ன⢮,  -
     ⠭     -ࢥ. ⥬ 㭪  ४-
      ᢮ 믮,   ࢥ  .

          +----------+    +----------+     +----------+
          |  A |    |  B |     |  C |
          +----------+    +----------+     +----------+
             -    -          -    -           -    -
     getty-  -    -          -    -           -    -
     -    -          -    -           -    -
             -    -          -    -           -    -
          +-------------------------------------------+ ନ-
          |  -    -          -    -           -    -  |  ࢥ
          +--+----+----------+----+-----------+----+--+
             |    |          |    |           |    |
          tty00  tty01    tty02  tty03     tty04  tty05

         㭮 13.13. 䨣  ନ ࢥ஬

*15.  짮⥫ ॣ   ⥬,  樯  ନ쭮
       ࠭  ଠ  ⮬,  ନ  ᪨,
     騬 㯯 ᮢ.  ⮩ 稭,  짮⥫  -
      ନ   "break",  ᨣ  뢠  
         㯯.  ᬮਬ  䨣 ⥬,  ன 
     ନ 䨧᪨    設,  ॣ 짮-
     ⥫ ᪨ ॠ  㣨 設 (㭮 13.13).  -
       ⤥쭮  砥  ⥬  ᮧ      㤠   ନ
     getty-.  ᫨     㤠 ⥬ ࠡ뢠  -
       ᮢ-ࢥ஢, ᫥ ⬥,     믮
     楤  ࢥ ⠭   祭. 
     믮 㭪樨 open 蠥, ࢥ 頥 ⭮  -
      , ࠧ뢠 ᢮   ନ.  ࠧ ⢫-
       뫪  ᨣ    뢠,  뢠  ⨥  
     "break",  ᠬ ᮢ, 室   㯯 ?
*16.   -  ᮡ,   設.   -
     ᪮  窨  ७, 뤥 饩  䨧᪮  (-
     쭮  㤠)  ⢨   ᮢ, ਭ
     ࠧ 設.  ॠ ⮣ .
*17. ᬮ७   9  㧪 ᮢ  窨 ࠭
      饭 । ᯮ짮 쭮 ன⢠ 㧪.
       ᫥      ⮣, ⮡  ᮧ
      প 㤠 ன 㧪 ?
*18.  ।,     㤠 設 (  ) 稫 ⠫
     ᡮ   ⮪ ⥢ ஢ 䨪஢  䠪.  -
     ࠡ⠩  奬  ⠭ 쭮 ⥬, 饩  㤠-
      ࢥ  ᠬ. ஬ ⮣, ࠧࠡ⠩ 奬  ⠭-
      ࢥ୮ ⥬, ⨢襩   ⠬.
*19.     頥  㤠 䠩,  ᪫祭 
     ⮣,   ᪠ 䠩   ᪮쪮 設.    ⢥
     ਬ  쬥   "/usr/src/uts/3b2/os",  "/usr" - ⠫, -
     騩 設 A, "/usr/src" - 窠 ஢    設  B,
     "/usr/src/uts/3b2"  -  窠  ஢  設 C. 室 १
     ᪮쪮 設   筮 祭 뢠 "᪠窮"
     (multihop). , ᫨  設 A  C  ।⢥-
      ⥢ , 뫪  १ 設 B 뫠   䥪⨢-
     .   ᮡ ॠ樨 "᪠窠"  ⥬  
     Newcastle   "஧筮" । ⥬.


                                    399
