Re: fds beyond 0/1/2

[nisse%lysator.liu.se@localhost (Niels Möller)]

der Mouse <mouse%Rodents-Montreal.ORG@localhost> writes:

> I had occasion to wish that ssh supported running remote commands with
> fds other than 0, 1, and 2 connected to useful things.
>
> Has anyone written up a spec for an extension to support this?  I don't
> recall seeing any, but that doesn't prove anything.

I haven't seen any.

I guess one ought to use MSG_CHANNEL_EXTENDED_DATA for the actual data,
but then you need some session handshaking to set up which fd:s should
be opened and which ids they should use in MSG_CHANNEL_EXTENDED_DATA.
All fd:s of the channel would then use a single window (or rather, one
in each direction) for flow control.

I take it this could be useful for both directions, although with the
client in chanrge of setting everything up. Do you want to be able to
setup bidirectional fd:s as well? That's more obscure, at least in the
context of shell scripting.

> If not, I've got some ideas I can write up and float for comment.
> if nobody but me cares, I suppose I can just hack something together
> and forget the issue. :)

I'm somewhat interested, but I'm not going to put in any real work any
time soon.

Regards,
/Niels

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