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Annotated edit history of ACL version 5, including all changes. View license author blame.
Rev Author # Line
1 PerryLorier 1 [Acronym] for __A__ccess __C__ontrol __L__ist.
2
3 Instead of having simple "User/Group/Other" permissions, the idea with ACL's is you have lists of users and groups that have permissions to some resource. For instance:
4 user=PerryLorier,rwx
5 user=MattBrown,rwx
6 user=JohnMcPherson,rx
7 group=WLUG,x
8 other=none
9
5 JohnMcPherson 10 would give PerryLorier,MattBrown read/write access to some executable, JohnMcPherson gets to read the executable, and everyone in the group WLUG would be able to execute it. Linux 2.6 supports ACLs on some filesystems (such as [Ext2]).
2 JohnMcPherson 11
12 For example, [Solaris] allows you to do this. You can use the commands
13 ''setfacl'' and ''getfacl'' to see file ACLs.
14 The way this is implemented in Solaris, the presence of file ACLs is
15 specified by a __+__ character next to the "normal" access indicators:
16
17 $ ls -ld Projects
18 drwxr-xr-x__+__ 3 user group 4096 2004-01-07 22:29 Projects
3 PhilMurray 19
20 [FreeBSD]s ACLs work much in the same way as [Solaris]. FreeBSD 5 with UFS2 supports ACLs by default (they can be enabled by recompilation for UFS1 and FreeBSD 4), but you have to mount your filesystem with
21 mount -o acl
22
23 for the ''setfacl'' tool to work.
2 JohnMcPherson 24
25 You can then use setfacl to give write access to multiple users and groups (for example), rather than having to create a new group and
26 adding all the requisite users to that group.