setfattr

Set extended attributes on files

TLDR

Set a user-defined attribute on a file

$ setfattr -n user.[attribute_name] -v "[value]" [path/to/file]

Set an attribute name without a value

$ setfattr -n user.[attribute_name] [path/to/file]

Remove a specific attribute from a file

$ setfattr -x user.[attribute_name] [path/to/file]

Restore attributes from a dump file

$ setfattr --restore=[dumpfile]

Modify attributes on a symbolic link itself (not target)

$ setfattr -h -n user.[attribute_name] -v "[value]" [path/to/symlink]

SYNOPSIS

setfattr [-h] -n name [-v value] pathname...setfattr [-h] -x name pathname...setfattr [-h] --restore=file

setfattr sets or modifies extended attributes on files and directories. Extended attributes are name-value pairs permanently associated with files, similar to environment variables but stored in the filesystem. Attribute names must be in the format namespace.name where namespace is typically user, system, security, or trusted.The user namespace is available to regular users for arbitrary data storage. System namespaces require appropriate capabilities or root privileges. Values can be specified as quoted strings with escape sequences, hexadecimal with 0x prefix, or base64 with 0s prefix.

PARAMETERS

-n, --name name

Specifies the name of the extended attribute to set

-v, --value value

Specifies the new value of the extended attribute. Value can be a string, hex (0x prefix), or base64 (0s prefix)

-x, --remove name

Remove the named extended attribute entirely

-h, --no-dereference

Do not follow symbolic links; operate on the link itself

--restore file

Restore extended attributes from a file created by getfattr --dump

--raw

Do not decode the attribute value

--version

Print version and exit

--help

Print help message

INSTALL

sudo apt install attr

sudo dnf install attr

sudo pacman -S attr

sudo apk add attr

sudo zypper install attr

brew install attr

nix profile install nixpkgs#attr

CAVEATS

Not all filesystems support extended attributes; common supported filesystems include ext2/3/4, XFS, Btrfs, and JFS. The user namespace may be disabled on some mount configurations. Attribute names have a maximum length of 255 bytes. Total attribute storage per file is filesystem-dependent (often 4KB-64KB).

HISTORY

Extended attributes support was added to Linux kernel 2.4 and became fully integrated in 2.6. The setfattr command is part of the attr package, developed as part of the XFS project at SGI and later adopted for general Linux filesystem use.