Understanding chmod Symbolic Notation and use of Octal

Many new users make mistakes (or have misunderstanding) while applying chmod on files or directories, because of a lack of informative knowledge of:

• Symbolic notation for ugo and rwx
• Use of octal numbers

So, in this answer I have provided some useful information that can help to understand correct symbolic notation and using octal numbers.

Solution 1:

Informative knowledge is provided with the help of The Linux Command-line as refrence/source.

• First of all it is very essential to know about ugo and rwx manner:

  

• Understanding of attribute which can be out put by ls-l:

  

• Applying Permission:

  

• Using Octal number:

  

Hence Following work same like:

chmod +rwx [file_name]
chmod 777 [file_name]

And

chmod 775 [file_name]
chmod ug+rwx,o=rx [file_name]

Hope this helps new users to understand and get knowledge about Symbolic Notation & using Octal number for chmod.

you can download pdf version of linux-command-line book from sourceforge-project