File mode syntax
File modes are described by a nine characters string that follows the same scheme as the 
ls shell command:
| 
Position
 | 
Character
 | 
Meaning
 | 
| 
1
 | 
-
 | 
The file owner cannot read it.
 | 
| 
 | 
r
 | 
The file owner can read it.
 | 
| 
2
 | 
-
 | 
The file owner cannot write it.
 | 
| 
 | 
w
 | 
The file owner can write it.
 | 
| 
3
 | 
-
 | 
The file owner cannot execute it.
 | 
| 
 | 
x
 | 
The file owner can execute it.
 | 
| 
 | 
S
 | 
The file owner cannot execute it and the 'setuid' bit is set.
 | 
| 
 | 
s
 | 
The file owner can execute it and the 'setuid' bit is set.
 | 
| 
4
 | 
-
 | 
The file group cannot read it.
 | 
| 
 | 
r
 | 
The file group can read it.
 | 
| 
5
 | 
-
 | 
The file group cannot write it.
 | 
| 
 | 
w
 | 
The file group can write it.
 | 
| 
6
 | 
-
 | 
The file group cannot execute it.
 | 
| 
 | 
x
 | 
The file group can execute it.
 | 
| 
 | 
S
 | 
The file group cannot execute it and the 'setgid' bit is set.
 | 
| 
 | 
s
 | 
The file group can execute it and the 'setgid' bit is set.
 | 
| 
7
 | 
-
 | 
Other users cannot read the file.
 | 
| 
 | 
r
 | 
Other users can read the file.
 | 
| 
8
 | 
-
 | 
Other users cannot write the file.
 | 
| 
 | 
w
 | 
Other users can write the file.
 | 
| 
9
 | 
-
 | 
Other users cannot execute the file.
 | 
| 
 | 
x
 | 
Other users can execute the file.
 | 
| 
 | 
T
 | 
Other users cannot execute the file and the 'sticky' bit is set.
 | 
| 
 | 
t
 | 
Other users can execute the file and the 'sticky' bit is set.
 | 
See also