     In     
.    --symbolic  In  ,   , 
  ,    .

 cd   

        cd   -
,    ,    ,   -
  .

      cd  ,   -
,   pwd    .  pwd (/bin/pwd) -
  ,    ,   ,   ,   
:

$ In -s /home/alex/grades /tmp/grades.old

$ pwd

/home/alex

$ cd /tmp/grades.old

$ pwd

/tmp/grades.old

$ /bin/pwd

$/home/alex/grades

          ,  -
 :

$ cd ..
$ pwd

/tmp
$ /bin/pwd

/tmp

rm:  

        .   
rm   , ,   Linux,  . 
           
 ,        
   .'      
.        ,     -
,             .

           
 .     cat ,   total 
,       :

$ Is -I sum

-rw-rr 1 alex pubs 981 May 24 11:05 sum

$ In -s sum total

$ rm sum

$ cat total

cat: total: No such file or directory       (    )

   DOS/Windows,       .
       ,      .

216                                               II.   Red Hat Linux