chown

change file owner and group

TLDR

Change owner

$ chown [user] [file]

Change owner and group

$ chown [user]:[group] [file]

Recursive change

$ chown -R [user]:[group] [directory/]

Change group only

$ chown :[group] [file]

SYNOPSIS

chown [options] owner[:group] file...

chown (change owner) modifies file ownership. It can change the user owner, group owner, or both. File ownership determines who has ultimate control over file permissions.The command typically requires root privileges to change ownership to other users.

PARAMETERS

-R, --recursive

Change files and directories recursively

-v, --verbose

Verbose output

-c, --changes

Report only changes

--reference=file

Use ownership from reference file

-h, --no-dereference

Affect symbolic links instead of targets

-f, --silent, --quiet

Suppress most error messages

--from=currentowner[:currentgroup]

Change only if current owner and/or group matches

--dereference

Affect the referent of each symbolic link (this is the default)

-H

If a command line argument is a symbolic link to a directory, traverse it (used with -R)

-L

Traverse every symbolic link to a directory encountered (used with -R)

-P

Do not traverse any symbolic links (default, used with -R)

--preserve-root

Fail to operate recursively on /

--no-preserve-root

Do not treat / specially (default)

OWNERSHIP FORMAT

user

Change user owner only

user:group

Change user and group

user:

Change user and set group to user's login group

:group

Change group only (same as chgrp)

WORKFLOW

$ # Change owner
sudo chown alice file.txt

# Change owner and group
sudo chown alice:developers file.txt

# Change owner, group to user's login group
sudo chown alice: file.txt

# Change group only
sudo chown :www-data file.txt

# Recursive change
sudo chown -R alice:developers project/

# Use reference file
sudo chown --reference=template.txt newfile.txt

# Change only if owned by specific user
sudo chown --from=bob alice file.txt

COMMON USES

Web server files:

$ sudo chown -R www-data:www-data /var/www/html

User home directory:

$ sudo chown -R alice:alice /home/alice

Restore ownership:

$ sudo chown -R $(whoami):$(whoami) ~/myproject

INSTALL

sudo apt install coreutils

sudo dnf install coreutils

sudo pacman -S coreutils

sudo apk add coreutils

sudo zypper install coreutils

brew install coreutils

nix profile install nixpkgs#coreutils

CAVEATS

Usually requires root/sudo. Changing ownership removes some security features (like setuid). Recursive changes can break system files. Cannot change ownership to users that don't exist. Symbolic links handled differently depending on options.