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Subject: Re: If not readdir() then what?
From: Trond Myklebust <trond.myklebust@fys.uio.no>
To: =?ISO-8859-1?Q?J=F6rn?= Engel <joern@lazybastard.org>
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Date: Mon, 09 Apr 2007 08:31:37 -0400
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On Mon, 2007-04-09 at 13:09 +0200, Jörn Engel wrote:
> That surely doesn't make life any easier for filesystem developers, I
> agree.  From that point of view, all telldir cookies should end their
> life at closedir time.  For "rm -r" it would be sufficient if the nfs
> client simply didn't seekdir at all.  For "ls -lR", this would return
> duplicate dentries.

Please go read the NFS spec. The only thing an NFS client has in order
to read a directory is a READDIR operation that in essence takes a
filehandle and a cookie as its arguments. Unless the server is able to
return the entire rest of the directory in one RPC reply, the client
needs to send a second READDIR operation with a cookie from the previous
READDIR operation. The server is expected to return cookies for _each_
entry in the directory.

That is a protocol limitation, not a client limitation.

Trond