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)
