From mboxrd@z Thu Jan  1 00:00:00 1970
From: Konrad Hinsen <konrad.hinsen@fastmail.net>
Subject: Re: Towards reproducibly Jupyter notebooks with Guix-Jupyter
Date: Mon, 21 Oct 2019 14:50:27 +0200
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To: Ludovic =?utf-8?Q?Court=C3=A8s?= <ludovic.courtes@inria.fr>
Cc: Guix Devel <guix-devel@gnu.org>

Hi Ludo,

>>> At the API level, there=E2=80=99s =E2=80=98inferior-for-channels=E2=80=
=99 which does that +
>>> registers a GC root + maintains a cache so that the second time you use
>>> a given instance of Guix it=E2=80=99s immediately available.
>>
>> Just what I need...
>
> Awesome, let us know how it goes!

Not so well...

If I run "guix environment" in the inferior, it's the inferior that
forks and runs the specified command in the newly created environment.
But the inferior doesn't have access to the tty, so this is bound to
fail for running interactive commands.

Unless there is some Linux magic that I am not aware of for transferring
the tty temporarily to another process, the fork would thus have to
happen in the main Guix process rather than in the inferior. But any
scheme I can come up with for creating a profile in the inferior and
using it in the main process ends up generating the same problem that I
am trying to solve: the need for a temporary reference (profile or GC
root) that must later be removed.

Cheers,
  Konrad.