chmod: Changing File/Directory Permissions

• Symbolic Notation::
  The syntax is:: chmod [-option][ugoa][+-=][rwx][st] file or directroy
  
  The meanings of the symbols are as follows:
  

  chmod	[-option]	[ugoa]	[+-=]	[rwx]	[st]	[file directroy]
  	-c →Report changes -R →Report changes -v → Verbosely report the process	u →user g →group o →other a →all	+ →increase permission - →subtract permission = →directly set permission	r → read permission w → write permission x → excute permission	s →suid or sgid t →sticky bit	ile or directory

  
  

  For example, to add write permission to the group of a file, you can use chmod g+w FILE. Also, chmod -v ug=rw,o+r FILE means giving the user and group read and write permissions, and others read permissions (resulting in "rw-rw-r--" permissions).

  For more examples and explanations of symbolic notation with chmod, please refer to the provided link.

  
  
  
• Numeric Notation:
  The basic syntax ischmod [-option] ### file or directroy。(where ### is a three-digit number).
  
  The relationship between numbers and permissions is as follows:

    0 → ---
    1 → --x
    2 → -w-
    3 → -wx
    4 → r--
    5 → r-x
    6 → rw-
    7 → rwx  

  For instance, using chmod 543 FILE would set the permissions of the file to "r-w r-- -wx" (matching the table).

  For more examples and explanations of numeric notation with chmod, please refer to the provided link.