NAME¶
chacl - change the access control list of a file or directory
SYNOPSIS¶
chacl acl pathname...
chacl -b acl dacl pathname...
chacl -d dacl pathname...
chacl -R pathname...
chacl -D pathname...
chacl -B pathname...
chacl -l pathname...
chacl -r pathname...
DESCRIPTION¶
chacl is an IRIX-compatibility command, and is maintained for those users
who are familiar with its use from either XFS or IRIX. Refer to the
SEE
ALSO section below for a description of tools which conform more closely
to the (withdrawn draft) POSIX 1003.1e standard which describes Access Control
Lists (ACLs).
chacl changes the ACL(s) for a file or directory. The ACL(s) specified
are applied to each file in the pathname arguments.
Each ACL is a string which is interpreted using the
acl_from_text(3)
routine. These strings are made up of comma separated clauses each of which is
of the form, tag:name:perm. Where tag can be:
- "user" (or "u")
- indicating that the entry is a user ACL entry.
- "group" (or "g")
- indicating that the entry is a group ACL entry.
- "other" (or "o")
- indicating that the entry is an other ACL entry.
- "mask" (or "m")
- indicating that the entry is a mask ACL entry.
name is a string which is the user or group name for the ACL entry. A null name
in a user or group ACL entry indicates the file's owner or file's group. perm
is the string "rwx" where each of the entries may be replaced by a
"-" indicating no access of that type, e.g. "r-x",
"--x", "---".
OPTIONS¶
- -b
- Indicates that there are two ACLs to change, the first is
the file access ACL and the second the directory default ACL.
- -d
- Used to set only the default ACL of a directory.
- -R
- Removes the file access ACL only.
- -D
- Removes directory default ACL only.
- -B
- Remove all ACLs.
- -l
- Lists the access ACL and possibly the default ACL
associated with the specified files or directories. This option was added
during the Linux port of XFS, and is not IRIX compatible.
- -r
- Set the access ACL recursively for each subtree rooted at
pathname(s). This option was also added during the Linux port of XFS, and
is not compatible with IRIX.
EXAMPLES¶
A minimum ACL:
chacl u::rwx,g::r-x,o::r-- file
The file ACL is set so that the file's owner has "rwx", the file's
group has read and execute, and others have read only access to the file.
An ACL that is not a minimum ACL, that is, one that specifies a user or group
other than the file's owner or owner's group, must contain a mask entry:
chacl u::rwx,g::r-x,o::r--,u:bob:r--,m::r-x file1 file2
To set the default and access ACLs on newdir to be the same as on olddir, you
could type:
chacl -b `chacl -l olddir | \
sed -e 's/.*\[//' -e 's#/# #' -e 's/]$//'` newdir
CAUTIONS¶
chacl can replace the existing ACL. To add or delete entries, you must
first do chacl -l to get the existing ACL, and use the output to form the
arguments to
chacl.
Changing the permission bits of a file will change the file access ACL settings
(see
chmod(1)). However, file creation mode masks (see
umask(1))
will not affect the access ACL settings of files created using directory
default ACLs.
ACLs are filesystem extended attributes and hence are not typically archived or
restored using the conventional archiving utilities. See
attr(5) for
more information about extended attributes and see
xfsdump(8) for a
method of backing them up under XFS.
SEE ALSO¶
getfacl(1),
setfacl(1),
chmod(1),
umask(1),
acl_from_text(3),
acl(5),
xfsdump(8)