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Linux/Unix
      -

             2010, Spring
•     (Owner)
•   (Group)
•     (Other)
Linux
littleq@ubuntu:~$ ls -l

  drwxr-xr-x   3   littleq   littleq   4096   2010-02-01   01:00   ~
  drwx------   2   littleq   littleq   4096   2010-02-04   11:53   amsn_received
  drwxr-xr-x   3   littleq   littleq   4096   2010-02-21   17:33   Downloads
  drwxr-xr-x   9   root      root      4096   2010-02-20   23:24   judge
  drwx------   2   littleq   littleq   4096   2010-01-25   17:22   mail
  drwxr-xr-x   8   littleq   littleq   4096   2010-02-18   16:28   OnlineJudge
  drwxr-xr-x   4   littleq   littleq   4096   2010-03-08   16:47   program
  drwxr-xr-x   7   littleq   littleq   4096   2010-03-08   22:42   public_html



 drwxr-xr-x 3 math11 mathlab 4096 2010-02-21 17:33 Downloads
Read   Write   eXecute


  R     W      X
   4    2      1
Linux
  4   2   1   4   x   1   4   x   1
d r w x r - x r - x



          7       5       5
• chmod:   SUID...
• chown:
• chgrp:
chmod-
• chmod   775 <       >

      rwxrwxr-x
          4 2 1 4 2 1 4 0 1

           7      7       5
• chmod   a+w,g+w <       >
           u
                  +       W
           g
                  -       R
           o      =       X
           a
chown-


• chown   [-R] <    >[:      ] <   >
• chown   -R monkey:mathlab banana
• chown   littleq aicp0529
chgrp-


• chgrp   <   > <   >
• chgrp   mathlab yellowfish
•                 •
    ASCII
    binary        •
       data


•
•
•
      block
      character

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Linux-Permission

  • 1. Linux/Unix - 2010, Spring
  • 2. (Owner) • (Group) • (Other)
  • 3. Linux littleq@ubuntu:~$ ls -l drwxr-xr-x 3 littleq littleq 4096 2010-02-01 01:00 ~ drwx------ 2 littleq littleq 4096 2010-02-04 11:53 amsn_received drwxr-xr-x 3 littleq littleq 4096 2010-02-21 17:33 Downloads drwxr-xr-x 9 root root 4096 2010-02-20 23:24 judge drwx------ 2 littleq littleq 4096 2010-01-25 17:22 mail drwxr-xr-x 8 littleq littleq 4096 2010-02-18 16:28 OnlineJudge drwxr-xr-x 4 littleq littleq 4096 2010-03-08 16:47 program drwxr-xr-x 7 littleq littleq 4096 2010-03-08 22:42 public_html drwxr-xr-x 3 math11 mathlab 4096 2010-02-21 17:33 Downloads
  • 4. Read Write eXecute R W X 4 2 1
  • 5. Linux 4 2 1 4 x 1 4 x 1 d r w x r - x r - x 7 5 5
  • 6. • chmod: SUID... • chown: • chgrp:
  • 7. chmod- • chmod 775 < > rwxrwxr-x 4 2 1 4 2 1 4 0 1 7 7 5 • chmod a+w,g+w < > u + W g - R o = X a
  • 8. chown- • chown [-R] < >[: ] < > • chown -R monkey:mathlab banana • chown littleq aicp0529
  • 9. chgrp- • chgrp < > < > • chgrp mathlab yellowfish
  • 10. • ASCII binary • data • • • block character