1、 权限
查看命令：# ls -la 或者 #ll
eg：
drwxr-xr-x. 2 dalianmao dalianmao 4096 Jul 11 08:01 Desktop
文件类型d
第一组（rwx）：文件拥有者权限
第二组（r-x）：文件拥有组权限位
第三组（r-x）：其他所有人
第一个dalianmao：代表拥有者
第二个dalianmao：代表拥有组
2、目录和文件权限
读 r（4）
读取文件内容
检查目录内容
写 w（2）
修改文件内容
改变目录内容
执行x（1）
执行文件
进入目录
3、修改权限命令：chmod chown chgrp
rwx : 4+2+1=7 可以任意组合
[user01@localhost ~]$ touch test1.py
[user01@localhost ~]$ ls
test1.py
[user01@localhost ~]$ ll
total 0
-rw-rw-r--. 1 user01 user01 0 Oct 2 00:07 test1.py
[user01@localhost ~]$ chmod 777 test1.py
[user01@localhost ~]$ ll
total 0
-rwxrwxrwx. 1 user01 user01 0 Oct 2 00:07 test1.py
[user01@localhost ~]$ chmod:
[root@localhost /]# ll
total 1702
dr-xr-xr-x. 2 root root 4096 Jul 13 06:41 bin
dr-xr-xr-x. 5 root root 1024 Jul 13 05:57 boot
drwxr-xr-x. 19 root root 3760 Sep 30 22:50 dev
drwxr-xr-x. 104 root root 12288 Oct 1 22:23 etc
-rw-r--r--. 1 root root 1642329 Apr 24 06:15 get-pip.py
drwxr-xr-x. 5 root root 4096 Oct 1 21:32 home
dr-xr-xr-x. 10 root root 4096 Jul 11 09:38 lib
dr-xr-xr-x. 9 root root 12288 Jul 13 06:41 lib64
drwx------. 2 root root 16384 Jul 11 07:40 lost+found
drwxr-xr-x. 2 root root 4096 Sep 23 2011 media
drwxr-xr-x. 3 root root 4096 Jul 11 07:53 mnt
drwxr-xr-x. 3 root root 4096 Jul 11 07:56 opt
dr-xr-xr-x. 146 root root 0 Sep 30 22:49 proc
dr-xr-x---. 4 root root 4096 Jul 11 12:14 root
dr-xr-xr-x. 2 root root 12288 Jul 13 06:41 sbin
drwxr-xr-x. 7 root root 0 Sep 30 22:49 selinux
drwxr-xr-x. 2 root root 4096 Sep 23 2011 srv
drwxr-xr-x 13 root root 0 Sep 30 22:49 sys
-rw-r--r--. 1 root root 0 Oct 2 00:12 test01.py
drwxrwxrwt. 13 root root 4096 Oct 1 21:41 tmp
drwxr-xr-x. 13 root root 4096 Jul 11 07:41 usr
drwxr-xr-x. 21 root root 4096 Jul 11 07:48 var
[root@localhost /]# chown user01 test01.py
[root@localhost /]# ll
total 1702
dr-xr-xr-x. 2 root root 4096 Jul 13 06:41 bin
dr-xr-xr-x. 5 root root 1024 Jul 13 05:57 boot
drwxr-xr-x. 19 root root 3760 Sep 30 22:50 dev
drwxr-xr-x. 104 root root 12288 Oct 1 22:23 etc
-rw-r--r--. 1 root root 1642329 Apr 24 06:15 get-pip.py
drwxr-xr-x. 5 root root 4096 Oct 1 21:32 home
dr-xr-xr-x. 10 root root 4096 Jul 11 09:38 lib
dr-xr-xr-x. 9 root root 12288 Jul 13 06:41 lib64
drwx------. 2 root root 16384 Jul 11 07:40 lost+found
drwxr-xr-x. 2 root root 4096 Sep 23 2011 media
drwxr-xr-x. 3 root root 4096 Jul 11 07:53 mnt
drwxr-xr-x. 3 root root 4096 Jul 11 07:56 opt
dr-xr-xr-x. 146 root root 0 Sep 30 22:49 proc
dr-xr-x---. 4 root root 4096 Jul 11 12:14 root
dr-xr-xr-x. 2 root root 12288 Jul 13 06:41 sbin
drwxr-xr-x. 7 root root 0 Sep 30 22:49 selinux
drwxr-xr-x. 2 root root 4096 Sep 23 2011 srv
drwxr-xr-x 13 root root 0 Sep 30 22:49 sys
-rw-r--r--. 1 user01 root 0 Oct 2 00:12 test01.py
drwxrwxrwt. 13 root root 4096 Oct 1 21:41 tmp
drwxr-xr-x. 13 root root 4096 Jul 11 07:41 usr
drwxr-xr-x. 21 root root 4096 Jul 11 07:48 varchgrp:
[root@localhost /]# chgrp user01 test01.py
[root@localhost /]# ll
total 1702
dr-xr-xr-x. 2 root root 4096 Jul 13 06:41 bin
dr-xr-xr-x. 5 root root 1024 Jul 13 05:57 boot
drwxr-xr-x. 19 root root 3760 Sep 30 22:50 dev
drwxr-xr-x. 104 root root 12288 Oct 1 22:23 etc
-rw-r--r--. 1 root root 1642329 Apr 24 06:15 get-pip.py
drwxr-xr-x. 5 root root 4096 Oct 1 21:32 home
dr-xr-xr-x. 10 root root 4096 Jul 11 09:38 lib
dr-xr-xr-x. 9 root root 12288 Jul 13 06:41 lib64
drwx------. 2 root root 16384 Jul 11 07:40 lost+found
drwxr-xr-x. 2 root root 4096 Sep 23 2011 media
drwxr-xr-x. 3 root root 4096 Jul 11 07:53 mnt
drwxr-xr-x. 3 root root 4096 Jul 11 07:56 opt
dr-xr-xr-x. 146 root root 0 Sep 30 22:49 proc
dr-xr-x---. 4 root root 4096 Jul 11 12:14 root
dr-xr-xr-x. 2 root root 12288 Jul 13 06:41 sbin
drwxr-xr-x. 7 root root 0 Sep 30 22:49 selinux
drwxr-xr-x. 2 root root 4096 Sep 23 2011 srv
drwxr-xr-x 13 root root 0 Sep 30 22:49 sys
-rw-r--r--. 1 user01 user01 0 Oct 2 00:12 test01.py
drwxrwxrwt. 13 root root 4096 Oct 1 21:41 tmp
drwxr-xr-x. 13 root root 4096 Jul 11 07:41 usr
drwxr-xr-x. 21 root root 4096 Jul 11 07:48 var