Linux Commands for Beginners-- Changing Permissions --chmod command

港控/mmm° 2023-06-28 11:19 20阅读 0赞

**In this part, I go over changing permissions of files and folders.  
  
  
1.COMMAND:  
 chmod  
DESCRIPTION:  
change file mode bits  
SYNOPSIS:  
chmod \[OPTION\] \[ugoa\]\[+-=\]\[rwx\] FILE  
  
OPTION:  
 \-R recursive, include objects in subdirectories  
  
uuser the owner of the file  
ggroupusers who are members of the file's group  
oothersusers who are neiter the owner of the file nor members of the file's group  
 aallall three of the above, same as ugo  
  
\+adds the specified modes to the specified classes  
\-removes the specified modes from the specified classes  
 =the modes specified are to be made the exact modes for the specified classes  
  
  
 rread read a file or list a directory's contents  
wwritewrite to a file or directory  
 xexecuteexecute a file or recurse a directory tree**

**If you have any problem in reading following example,maybe you need to know more about file permission.Want more information?You can click my previous tutorial [File Permission][]**

**Example:  
  
piniheaven@fish:~/Documents/tutorial$ ls -l  
total 0  
\-rw-rw-r-- 1 jack piniheaven 0 Aug 25 21:42 essay.txt  
piniheaven@fish:~/Documents/tutorial$ sudo  chmod u+x essay.txt \#give user the permission to execute essay.txt  
\[sudo\] password for piniheaven:   
piniheaven@fish:~/Documents/tutorial$ ls -l  
total 0  
\-rwxrw-r-- 1 jack piniheaven 0 Aug 25 21:42 essay.txt  
  
  
piniheaven@fish:~/Documents/tutorial$ sudo chmodu-r essay.txt  \#remove user's permission of reading essay.txt  
piniheaven@fish:~/Documents/tutorial$ ls -l  
total 0  
\--wxrw-r-- 1 jack piniheaven 0 Aug 25 21:42 essay.txt  
  
  
piniheaven@fish:~/Documents/tutorial$ sudochmod uo+r essay.txt\#give user and others the permission of reading essay.txt  
piniheaven@fish:~/Documents/tutorial$ ls -l  
total 0  
\-rwxrw-r-- 1 jack piniheaven 0 Aug 25 21:42 essay.txt  
  
  
  
  
piniheaven@fish:~/Documents/tutorial$ sudo chmod a=x essay.txt\#assign user,group and others only the permission to execute essay.txt  
piniheaven@fish:~/Documents/tutorial$ ls -l  
total 0  
\---x--x--x 1 jack piniheaven 0 Aug 25 21:42 essay.txt  
  
  
  
piniheaven@fish:~/Documents/tutorial$sudo chmod ugo+rwx essay.txt \#assign user,group and others with the permission of read,write and excute  
piniheaven@fish:~/Documents/tutorial$ ls -l  
total 0  
\-rwxrwxrwx 1 jack piniheaven 0 Aug 25 21:42 essay.txt  
  
  
piniheaven@fish:~/Documents/tutorial$ cd ..  
piniheaven@fish:~/Documents$sudo chmod -R a=rx tutorial\#assign user,group and others with the permission of read and excute, including it's subdirectories  
  
piniheaven@fish:~/Documents$ ls -l  
total 32  
drwxrwxr-x 4 piniheaven piniheaven 4096 Aug 22 12:16 assemble  
......  
......  
dr-xr-xr-x 2 jack piniheaven 4096 Aug 25 21:42 tutorial  
piniheaven@fish:~/Documents$ ls -l tutorial/  
total 0  
\-r-xr-xr-x 1 jack piniheaven 0 Aug 25 21:42 essay.txt**

[File Permission]: http://blog.csdn.net/piniheaven/article/details/9238135