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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 com-
       mands, ...).

       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 permis-
       sions.

       The -x (--remove) and -X (--remove-file) options remove ACL entries. It
       is not an error to remove an entry which	 does  not  exist.   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, set-
       facl operates on the file mode permission bits. If the ACL does not fit
       completely  in the permission bits, setfacl modifies the file mode per-
       mission 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 hap-
	   pens).

       --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,
	   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
	   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	inter-
	   preted 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  per-
       missions: 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 permis-
	   sions 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
	   permissions 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 --access 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@bestbits.at>.

       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)