This is an incomplete / broken idea that I'm just posting as a
discussion point. I don't intend to pursue this idea further at the
moment.
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The major issue with it is that it uses a custom binary protocol
between nbdkit & the external process. That's a pain for anyone to
parse and generate. Ideally we could use an existing protocol, but
the problem with that is it adds both dependencies to the plugin and a
need for the external process to have a library or implementation for
that protocol, which may not be any better.
Rich.
