From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <b97ed081ef4f66fcf0eaffc4b24adfd7@terzarima.net>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] the meaning of group
From: Charles Forsyth <forsyth@terzarima.net>
Date: Mon, 28 Jan 2008 22:10:59 +0000
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> explain how it could be more elaborate.

it's completely up to them (as it is to fossil or kfs, which use a file /adm/users that they maintain themselves).
the location and representation of group membership, and its interpretation are all independent things.
that is, all three aspects could be handled by different services: for instance something like google's Chubby could
store a group map in s-expression form [unknown to chubby] but read and interpreted by other servers, even with
different interpretations of what that representation meant)

as another example, in a flash file system we did for inferno, there wasn't an /adm/users but a ctl file
of some sort received requests to manage a group membership similar to fossil console requests.

as a further example, SPKI's public key certificates can be used in various ways to establish group membership,
typically by producing a certificate stating that a given principal (represented by a public key)
is a member of a local name (ie group) rooted at another principal's public key. the latter principal
might correspond to the `owner' of a resource.  this example is more interesting than some of the others
because there isn't (in general) a group membership list; also SPKI itself allows delegation and compound
group names.

in your case, however, a simple scheme might have the kernel (or just a device) accept a ctl request that added
or removed a user name from a local group table, and then system start up script(s) would load the table from some agreed source
(and presumably one that's adequately reliable).  i think something like that was mentioned,
if not discussed, many months ago on the list.