| chmod is a command in UNIX that allows you to set
access privileges to Owner - Group - Other, it is very simple
Usually you are guided with the format of ten consecutive letters of
either -, D, R, W, X where D means directory, R means read, W means
write and X means Execute.
| |
Owner |
Group |
Other |
| Read |
On or Off (1) |
On or Off (4) |
On or Off (7) |
| Write |
On or Off (2) |
On or Off (5) |
On or Off (8) |
| Execute |
On or Off (3) |
On or Off (6) |
On or Off (9) |
Now that we have given the states of on or off numbers, lets see
how to interpret a string of instructions.
| dir or file |
Owner Privalages |
Group Privalages |
Other Users
Privalages |
| 1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
| D OR - |
R OR - |
W OR - |
X OR - |
R OR - |
W OR - |
X OR - |
R OR - |
W OR - |
X OR - |
drwxrwxrwx = D means that this is a directory to be modified, the
first rwx means OWNER gets read and write and execute privalages, the
second rwx means Group gets them too and the third rwx means Others as
well.
-rw-r--r-- = This string means this is a file (d is absent) Owner
gets read write privalages but not execute (first three after
directory character are rw-) Group gets read only (r--), and other get
read only as well.
Now what about those numbers (CHMOD 700 for example means
-rwx------ ! and CHMOD 444 means -r--r--r-- !)
Those numbers are the message that goes to the server when you set
privileges, there is a way to interpret them that i will explain later
(when we find more time for the advanced section of the website)
Yazeed Madaeen 2003 |
