From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: References: <36c9016b7918c302d777f1a605fc107f@brasstown.quanstro.net> <2CBEED8D-800D-40C8-8182-162695D9FF30@9srv.net> <45fe7ac7a1dab989624aa4ed2b376ff9@brasstown.quanstro.net> Date: Wed, 4 Feb 2015 15:29:17 +0100 Message-ID: From: Giacomo Tesio To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: multipart/alternative; boundary=001a11c33a7831b1ba050e4403c8 Subject: Re: [9fans] wstat and atomic directory change Topicbox-Message-UUID: 4000a876-ead9-11e9-9d60-3106f5b1d025 --001a11c33a7831b1ba050e4403c8 Content-Type: text/plain; charset=UTF-8 And unfortunately I cannot figure out any alternative, either. :-( An interesting point is: why directory entries can be read but cannot be written? I mean we use Tcreate to create a new file in a dir, while to be uniform with files, we should use a Twrite, appending a corresponding stat structure at the end of a directory entry. However this solution probably has not been adopted to enable safe concurrency in the file creation and removal. However this asymmetry shows that directories cannot be (pratically) handled in the same way of files. Giacomo 2015-02-04 15:06 GMT+01:00 erik quanstrom : > > You are right. > > But since protocol customizations goes against that same ideal, what's > the > > plan9 way of dealing with a feature X (in this specific case atomic file > > moves)? > > > > > > > this requires delving into the namespace to tell that the directories > are > > > still under the > > > same mount, and some non-uniform operations. > > > > > > > Good point. But thus, what are the alternatives? > > i wasn't holding out. i don't have any suggestions. > > - erik > > --001a11c33a7831b1ba050e4403c8 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
And unfortunately I cannot figure out any alternative, eit= her. :-(

An interesting point is: why directory entries = can be read but cannot be written? I mean we use Tcreate to create a new fi= le in a dir, while to be uniform with files, we should use a Twrite, append= ing a corresponding stat structure at the end of a directory entry.

However this solution probably has not been adopted to en= able safe concurrency in the file creation and removal.=C2=A0
However this asymmetry shows that directories cannot be (pratic= ally) handled in the same way of files.


=
Giacomo


2015-02-04 15:06 GMT+01:00 erik quanstrom <qua= nstro@quanstro.net>:
> You are right.
> But since protocol customizations goes against that same ideal, what&#= 39;s the
> plan9 way of dealing with a feature X (in this specific case atomic fi= le
> moves)?
>
>
> > this requires delving into the namespace to tell that the directo= ries are
> > still under the
> > same mount, and some non-uniform operations.
> >
>
> Good point. But thus, what are the alternatives?

i wasn't holding out.=C2=A0 i don't have any suggestions.
- erik


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