How to change file access permission in linux

By Weldon James On Jul 17, 2015

How to change file access permission in linux

1. Name
chmod [man page] – change file access permissions

2. Synopsis

chmod [OPTION]... MODE[,MODE]... FILE...
chmod [OPTION]... OCTAL-MODE FILE...
chmod [OPTION]... --reference=RFILE FILE...

3. Frequently used options in file access permission in linux

-R, --recursive
      change files and directories recursively
-c, --changes
      like verbose but report only when a change is made
-v, --verbose
      output a diagnostic for every file processed

4. Basics

r : read (user can read the file, or list a given directory)
w : write (user can write to the file, or create file or directory in the directory)
x : execute (user can execute the file, or enter directory)

$ ls -ld dir/

chmod octal and symbolic guide

5. Examples

5.1. Octal Mode

Let’s see how we can change file.txt permissions to rwxr-xr– with octal mode:

$ chmod 764 file.txt

use octal chmod to change file permitions

5.2. Symbolic Specification

Symbolic specification is just another way to change file and directory permissions. In the next example we will change file.txt’s permissions to rwxr-xr– with a following symbolic specification:

$ chmod u=rwx,g=rx,o=r file.txt

use symbolic chmod to change file permitions
Source taken from http://linuxconfig.org/

linux