Thomas writes:
>
> just a little question: is there anything like the immutable and
> append only flags of ext2 (and for instance FFS in BSD) in XFS
> too - maybe somehow realized via extended attributes or in
> any other way?
>
I didn't know what "immutable and append only flags" were :)
Looking in the ext2 CHANGES file:
- New file attributes:
- Immutable files cannot be modified. Data cannot be written to
these files. They cannot be removed, renamed and new links cannot
be created. Even root cannot modify the files. He has to remove
the immutable attribute first.
- Append-only files: can only be written in append-mode when writing.
They cannot be removed, renamed and new links cannot be created.
Note: files may only be added to an append-only directory.
- No-dump files: the attribute is not used by the kernel. My port
of dump uses it to avoid backing up files which are not important.
No, I don't believe we have any equivalents.
Immutable sounds pretty much what one could achieve using the
standard access modes except for ROOT being disallowed to change
the file (without first setting the attribute).
OOI, how useful is this attribute ?
The No-Dump attribute (not that you asked ;-), I guess, could
be achieved rather easily by modifying xfsdump to use a particular
Extended Attribute.
The extended attributes used in XFS in Linux are:
1. DMAPI info
2. ACL info (coming soon).
Other uses of EA in IRIX which _may_ be added to XFS in Linux are:
3. MAC (Mandatory Access Controls) info
4. File capability info
Cheers,
Tim.
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