First, rights management
1 ls -l
rwxrwxrwx
Left three: the definition of user (owner) permission
In three: rights defined group of
The right three: define the rights of other
1, the process security context
a, process applications for access to the file:
Owner of the file owner and processes are the same, if the same, then the application owner permissions.
Otherwise, the owner checks whether the process is a set of files, if it is, is a set of permissions the application;
Otherwise, you can use other rights of other
2, the authority:
r: read, read
w：write，写
x: excute, execution
a, file:
r: available data files
Data files can be modified: w
x: this file can be run as a process
b, directory:
r: use ls command to get a list of all the files in it: but you can not get more information, such as ls -l
w: you can modify the list of files in this directory: that is, create or delete files
x: can cd to this directory, it can use ls -l to get detailed information about the properties of all files
c, mode: rwxrwxrwx
d、ownership：user，group
3, combination of rights mechanisms
---:：000 0
--x：001 1
-w-:010 2
-wx:011 3
r-- :100 4
r-x：101 5
rw-:110 6
rwx:111 7