Re: [9fans] Q: moving directories? hard links?

[Bakul Shah <bakul@bitblocks.com>]

On Thu, 21 Apr 2011 15:44:32 -0000 smiley@zenzebra.mv.com  wrote:
> Bakul Shah <bakul@bitblocks.com> writes:
>
> > Ask yourself *why* do you need it. Is it just convenience
> > (what you are used to) or is there something you do that
> > absolutely requires hard links? Next compare the benefit
> > of hardlinks to their cost. It is worth it?
>
> I'm trying to create a data structure in the form of a directed acyclic
> graph (DAG).  A file system would be an ideal way to represent the data,
> except that P9 exposes no transaction to give a node more than one name.

A FS is not necessarily the ideal way.

> I could store the data in a P9 file system tree and maintain a set of
> links in, say $home/lib/bindrc.d/myDAG.  But, every time I
> copy/relocate/distribute the tree, I would have to include the myDAG
> bindings.  It would be much nicer if the structure of the data embodied
> in the data itself.
>
> ATM, I'm thinking about creating a DAGfs backed by pq.  That way,
> standard file utilities could still be used be used to manipulate the
> data.  However, that solution strikes me as being suspiciously similar
> to creating a new disk file system.  (How many do we have, already?)

Not a disk FS, just a naming FS.  You can overlay your naming
FS on top of an existing disk based FS.  In effect each named
file in this naming FS maps to a "canonical name" of a disk
based file.  You can implement linking via a ctl file or
something.