Re: save-buffer in tar-mode

[Richard Stallman]

      What tar-mode would ideally want to do
    > is copy the tar data to auxiliary buffer B so buffer A could be in 
multibyte
    > and buffer A in unibyte, but copying 25MB of tar data is a bit costly, so
    > instead we could offer a primitive that swaps the buffer_text of
    > two buffers.

I think it would work, and it might be a good idea.
However, something about it seems not quite right.
I have the feeling that the really right thing to do would
be different in some detail.

Perhaps attempting to write the buffer A into a file should actually
write buffer B into the file.