Re: hidden buffers for async

[Nic Ferrier <nferrier@tapsellferrier.co.uk>]

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Richard Stallman <rms@gnu.org> writes:

>     Something that would help a great deal is if one could create a buffer
>     that was hidden, ie: it did not ordinarily appear in the buffer list
>     and was not returned by a call to:
>
> 	(get-buffer buffername)
>
> Why do you think this is necessary?
> I don't see what problem this would solve.

Buffers are more convieniant (and more efficient) than strings for
large amounts of data. But buffers are very visible to the user and
that makes them less attractive for storing purely temporary or
transient data.


A concrete example. IMAP does file transfers with variable sized
chunks. It states the chunk size and then sends that many bytes of the
file. But you don't recieve all the bytes at once in an elisp async
reciever. 

I wanted to use a buffer to collect the data from the chunks while the
file transfer was still going on.

But IMAP can be asked to download lots of files at once and will be
chunking them all. So I wanted to have lots of chunk buffers, one for
each file transfer. When the files are downloaded they can be put
straight into the correct mode for displaying the file.

So there might be 10 or 20 (or 1000) buffers all recieving chunks of
files from IMAP. But these are purely temporary objects, until IMAP
sends a "file downloaded" status message the buffers are just data
stores. So I wanted to hide them from the user.

I think there are a lot of protocols where this happens. HTTP is
similar and so is NNTP.



Nic