CHACL(1) Access Control Lists CHACL(1)
chacl - change the access control list of a file or directory
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...
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 descrip-
tion of tools which conform more closely to the (withdrawn draft) POSIX 1003.1e standard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", "---".
-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.
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 exe-
cute, 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
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.
getfacl(1), setfacl(1), chmod(1), umask(1), acl_from_text(3), acl(5), xfsdump(8)
September 2001 ACL File Utilities CHACL(1)