chmod 🔐

Modifies file/directory permissions (See here or here for more details).

Permission expressions are mostly formatted as [ugoa][+-=][rwx]:

Symbol Meaning
r Read
w Write
x Execute
Symbol Meaning
u User (owner of the file/directory)
g Group (of the file/directory)
o Other users/groups
a All users/groups

Grant all permissions to everyone; a+rwx or 777

chmod a+rwx some-file
# or
chmod 777 some-file

Make a file executable for everyone +x

chmod +x some-file
# or
chmod a+x some-file

Make a file executable only for the User (owner) u+x

chmod u+x some-file

Disallow Group and Others to read/write/execute go-rwx

chmod go-rwx some-file

Apply the same User (owner) permissions to the Group =u

chmod g=u some-file

Rewrite permissions for the Group and Others =

chmod go=rw some-file

Clear permissions for the Group and Others =

chmod go= some-file

Clear all permissions =

chmod a= some-file

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