Re: Versioning file system

From: alan
Date: Fri Jun 15 2007 - 19:01:34 EST

On Fri, 15 Jun 2007, Kok, Auke wrote:

Jack Stone wrote:
I hope I got the CC list right. Apologies to anyone in didn't include
and anyone I shouldn't have included.

The basic idea is to include an idea from VMS that seems to be quite
useful: version numbers for files.


have you looked into ext3cow? it allows you to take snapshots of the entire ext3 fs at a single point, and rollback / extract snapshots at any time later. This may be sufficient for you and the implementation seems to be rather stable already.

As long as there is only one person using the file system. Rolling back the entire filesystem may work well for you, but screw up something else someone else is doing.

And what kind of rights do you have to assign to the user to do that level of snapshot and rollback? You have to assume that there are more than one user and that they have less than root privileges.

"ANSI C says access to the padding fields of a struct is undefined.
ANSI C also says that struct assignment is a memcpy. Therefore struct
assignment in ANSI C is a violation of ANSI C..."
- Alan Cox
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