Re: [Nbd] [PATCH] Add "temporary" option, and ability to create files.

[Alex Bligh <alex@...872...>]

Wouter,

(replying to myself)

--On 9 June 2011 16:19:02 +0100 Alex Bligh <alex@...872...> wrote:

> I think the answer here is because there is no way from prerun
> or postrun to feed back the name of the temporary file created. Just
> to be clear, what it's doing is creating a temporary file based on
> the pathname specified in the export session, and using that. So multiple
> clients can say "I want a 50Gig disk that will go away after I use
> it". Pre-run could create one, with a fixed filename, but I see
> no way to avoid overwriting the files of existing clients.

Oh, there were a couple of other reasons.

Firstly I want to introduce a negotiated option (partly to test whether
option negotiation can work - I was just going to write some code
and see what people thought) where the client can ask for a disk
size. That's not fantastically useful in nbd-server without the
temporary file option, though it would be with it (with the
configured size acting as a maximum). I thought I'd get the
temporary file stuff in first as it is reasonably non-destructive.

Secondly, it will simplify the test suite a bit (no need
for that dd, a trap() to delete the file, etc.).

--
Alex Bligh