Re: [9fans] p9sk2

[Russ Cox <rsc@swtch.com>]

> I was trying to document -O in cpu(1) which is undocumented, it enables

It is like -R (run the server aka remote side of the protocol)
except that it runs the pre-9P2000 server side.
It is undocumented because you never say it yourself
on the command line (just like -R) and because it needs
to go away.  It persists only because of drawterm.

> 'p9sk2', but what that does is rather confusing, my initial guess was that it
> was a deprecated version of p9sk1,  but lookman p9sk2 pointed me at
> factotum(4) which says:
>
> p9sk1   a Plan 9 shared key protocol described in
>       authsrv(6)'s ``File Service'' section.
> p9sk2   a variant of p9sk1 described in authsrv(6)'s
>       ``Remote Execution'' section.

Authsrv(6) is still describing the pre-9P2000 protocols.
Except for the 9P stuff, it's still accurate and does describe
p9sk1 and p9sk2 (without naming them) in the sections
mentioned.

/sys/doc/auth.ps has a quick sketch of p9sk1 that may well
be easier to digest, and
http://swtch.com/usr/local/plan9/src/cmd/auth/factotum/p9sk1.c
has a similar sketch and tells you exactly what messages are
in play in both.

P9sk2 exists only for backwards compatibility when connecting
to old (pre-9P2000) services.  It does not authenticate the server
to the client, only vice versa.  It was used by cpu in the old days,
as you've no doubt figured out.

> (Oh, and it seems that factotum(4) in p9p and in Plan 9 are out of sync..
> *sigh*)

Both factotum(4)s accurately describe their respective factotums.
Go ahead.  Complain that the factotum programs are out of sync too.

> This all started because cpu -O is used in
> http://plan9.bell-labs.com/wiki/plan9/Drawterm_to_your_terminal/
>
> My guess is that it's needed for drawterm to be able to connect, will dt2k
> fix that? what is up with dt2k anyway?

As it always is, progress is slow.  Skip and Brucee have added Windows
support to dt2k, and Andrey has been maintaining it.  I use it for days
at a time without problems on Linux except that snarf doesn't work.
Others have reported problems.  At the moment, it's really far down
on my to do list, and no one else is stepping up to the plate.

Russ