Re: [9fans] πp

[Sape Mullender <sape@plan9.bell-labs.com>]

Are we talking about πP or 9P?

ΠP doesn't have Twalk.  It has open, which combines clone, walk, and open from
9P.  Before you start jumping up and down and telling me that you can't open
without revieing the qids from the walk (to check them for mount points), let
me tell you that we are also tackling mount tables.  Mount tables will no longer
match qids but longest prefix path names.
We know the semantics are different.  But you have to look hard to find
realistic situations where the difference matters.

I intend to write a πP design document that explains the whole concept in
excruciating detail.  There's a lot more to it than just changing walk and
open.

	Sape


> From: lucho@ionkov.net
> To: 9fans@9fans.net
> Reply-To: 9fans@9fans.net
> Date: Thu Oct 14 23:13:59 CES 2010
> Subject: Re: [9fans] πp
>
> It can't be dealt with the current protocol. It doesn't guarantee that
> Topen will be executed once Twalk is done. So can get Rerrors even if
> Twalk succeeds.
>
> 2010/10/13 Venkatesh Srinivas <me@acm.jhu.edu>:
> >> 2) you can't pipeline requests if the result of one request depends on the
> >> result of a previous. for instance: walk to file, open it, read it, close
> >> it.
> >> if the first operation fails, then subsequent operations will be invalid.
> >
> > Given careful allocation of FIDs by a client, that can be dealt with -
> > operations on an invalid FID just get RErrors.
> >
> > -- vs
> >