Set file access control lists.

      setfacl [-bkndRLPvh] [{-m|-x} acl_spec] [{-M|-X} acl_file] file ...

      setfacl --restore=file

   -b, --remove-all
          Remove all extended ACL entries. The base ACL entries of the owner, group and others are retained.

   -k, --remove-default
          Remove the Default ACL. If no Default ACL exists, no warnings are issued. 

   -n, --no-mask
          Do not recalculate the effective rights mask. The default behavior of setfacl is to recalculate the ACL mask entry,
          unless a mask entry was explicitly given. The mask entry is set to the union of all permissions of the owning group,
          and all named user and group entries. (These are exactly the entries affected by the mask entry). 

          Do recalculate the effective rights mask, even if an ACL mask entry was explicitly given. (See the -n option.) 

   -d, --default
          All operations apply to the Default ACL. Regular ACL entries in the input set are promoted to Default ACL entries.
          Default ACL entries in the input set are discarded. (A warning is issued if that happens). 

          Restore a permission backup created by 'getfacl -R' or similar.
          All permissions of a complete directory subtree are restored using this mechanism.
          If the input contains owner comments or group comments, setfacl attempts to restore the owner and owning group.
          If the input contains flags comments (which define the setuid, setgid, and sticky bits), setfacl sets those
          three bits accordingly; otherwise, it clears them. This option cannot be mixed with other options except '--test'. 

          Test mode. Instead of changing the ACLs of any files, the resulting ACLs are listed. 

   -R, --recursive
          Apply operations to all files and directories recursively. This option cannot be mixed with '--restore'. 

   -L, --logical
          Logical walk, follow symbolic links to directories. The default behavior is to follow symbolic link arguments, and
          skip symbolic links encountered in subdirectories.
          Only effective in combination with -R. This option cannot be mixed with '--restore'. 

   -P, --physical
          Physical walk, do not follow symbolic links to directories. This also skips symbolic link arguments.
          Only effective in combination with -R. This option cannot be mixed with '--restore'. 

   -v, --version
          Print the version of setfacl and exit. 

   -h, --help
          Print help explaining the command line options.

   --     End of command line options. All remaining parameters are interpreted as file names, even if they start with a dash.

   -      If the file name parameter is a single dash, setfacl reads a list of files from standard input.


The setfacl utility recognizes the following ACL entry formats (blanks inserted for clarity):

[d[efault]:] [u[ser]:]uid [:perms]
    Permissions of a named user. Permissions of the file owner if uid is empty.

[d[efault]:] g[roup]:gid [:perms]
    Permissions of a named group. Permissions of the owning group if gid is empty.

[d[efault]:] m[ask][:] [:perms]
    Effective rights mask

[d[efault]:] o[ther][:] [:perms]
    Permissions of others.

Whitespace between delimiter characters and non-delimiter characters is ignored.

Proper ACL entries including permissions are used in modify and set operations. (options -m, -M, --set and --set-file).
Entries without the perms field are used for deletion of entries (options -x and -X).

For uid and gid you can specify either a name or a number.

The perms field is a combination of characters that indicate the permissions: read (r), write (w), execute (x), execute only if the file is a directory or already has execute permission for some user (X). Alternatively, the perms field can be an octal digit (0-7).

Automatically created entries

Initially, files and directories contain only the three base ACL entries for the owner, the group, and others. There are some rules that need to be satisfied in order for an ACL to be valid:

If the environment variable POSIXLY_CORRECT is defined, the default behavior of setfacl changes as follows: All non-standard options are disabled. The ''default:'' prefix is disabled. The -x and -X options also accept permission fields (and ignore them).


Grant an additional user read access:

setfacl -m u:lisa:r file

Revoke write access from all groups and all named users (using the effective rights mask):

setfacl -m m::rx file

Remove a named group entry from a file's ACL:

setfacl -x g:staff file

Copy the ACL of one file to another:

getfacl file1 | setfacl --set-file=- file2

Copying the access ACL into the Default ACL:

getfacl --access dir | setfacl -d -M- dir

“Originally, when I wrote the song 'The Sensual World' I had used text from the end of 'Ulysses.' When I asked for permission to use the text, I was refused, which was disappointing” ~ Kate Bush

Related linux commands

getfacl - get file access control lists.
chgrp - Change group ownership.
chown - Change file owner and group.
umask - Users file creation mask.acl(5)

Copyright © 1999-2024
Some rights reserved