SETFACL(1)						       Access Control Lists							SETFACL(1)

NAME

       setfacl - set file access control lists

SYNOPSIS

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

       setfacl --restore=file

DESCRIPTION

       This  utility  sets  Access  Control  Lists  (ACLs) of files and directories.  On the command line, a sequence of commands is followed by a
       sequence of files (which in turn can be followed by another sequence of commands, ...).

       The options -m, and -x expect an ACL on the command line. Multiple ACL entries are separated by comma characters (`,'). The options -M, and
       -X read an ACL from a file or from standard input. The ACL entry format is described in Section ACL ENTRIES.

       The  --set  and --set-file options set the ACL of a file or a directory. The previous ACL is replaced.  ACL entries for this operation must
       include permissions.

       The -m (--modify) and -M (--modify-file) options modify the ACL of a file or directory.	ACL entries for this operation must  include  per-
       missions.

       The  -x	(--remove)  and -X (--remove-file) options remove ACL enries. Only ACL entries without the perms field are accepted as parameters,
       unless POSIXLY_CORRECT is defined.

       When reading from files using the -M, and -X options, setfacl accepts the output getfacl produces.  There is at	most  one  ACL	entry  per
       line. After a Pound sign (`#'), everything up to the end of the line is treated as a comment.

       If setfacl is used on a file system which does not support ACLs, setfacl operates on the file mode permission bits. If the ACL does not fit
       completely in the permission bits, setfacl modifies the file mode permission bits to reflect the ACL as	closely  as  possible,	writes	an
       error message to standard error, and returns with an exit status greater than 0.

   PERMISSIONS
       The  file  owner  and  processes capable of CAP_FOWNER are granted the right to modify ACLs of a file. This is analogous to the permissions
       required for accessing the file mode. (On current Linux systems, root is the only user with the CAP_FOWNER capability.)

   OPTIONS
       -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).

       --mask
	   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=file
	   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, and setfacl is run by root, the owner and owning group of all  files
	   are restored as well. This option cannot be mixed with other options except `--test'.

       --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. The default behavior is to follow symbolic link arguments, and to skip symbolic links encountered
	   in subdirectories. This option cannot be mixed with `--restore'.

       -P, --physical
	   Physical walk, skip all symbolic links. This also skips symbolic link arguments.  This option cannot be mixed with `--restore'.

       --version
	   Print the version of setfacl and exit.

       --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.

   ACL ENTRIES
       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:

       *   The three base entries cannot be removed. There must be exactly one entry of each of these base entry types.

       *   Whenever an ACL contains named user entries or named group objects, it must also contain an effective rights mask.

       *   Whenever an ACL contains any Default ACL entries, the three Default ACL base entries (default owner, default group, and default others)
	   must also exist.

       *   Whenever a Default ACL contains named user entries or named group objects, it must also contain a default effective rights mask.

       To help the user ensure these rules, setfacl creates entries from existing entries under the following conditions:

       *   If an ACL contains named user or named group entries, and no mask entry exists, a mask entry containing the	same  permissions  as  the
	   group  entry  is created. Unless the -n option is given, the permissions of the mask entry are further adjusted to include the union of
	   all permissions affected by the mask entry. (See the -n option description).

       *   If a Default ACL entry is created, and the Default ACL contains no owner, owning group, or others entry, a copy of the ACL owner,  own-
	   ing group, or others entry is added to the Default ACL.

       *   If a Default ACL contains named user entries or named group entries, and no mask entry exists, a mask entry containing the same permis-
	   sions as the default Default ACL's group entry is added. Unless the -n option is given, the permissions of the mask entry  are  further
	   adjusted to inclu de the union of all permissions affected by the mask entry. (See the -n option description).

EXAMPLES

       Granting an additional user read access
	      setfacl -m u:lisa:r file

       Revoking write access from all groups and all named users (using the effective rights mask)
	      setfacl -m m::rx file

       Removing a named group entry from a file's ACL
	      setfacl -x g:staff file

       Copying the ACL of one file to another
	      getfacl file1 | setfacl --set-file=- file2

       Copying the access ACL into the Default ACL
	      getfacl -a dir | setfacl -d -M- dir

CONFORMANCE TO POSIX 1003.1e DRAFT STANDARD 17
       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).

AUTHOR

       Andreas Gruenbacher, <a.gruenbacher@computer.org>.

       Please send your bug reports, suggested features and comments to the above address.

SEE ALSO

       getfacl(1), chmod(1), umask(1), acl(5)

May 2000							ACL File Utilities							SETFACL(1)