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Date: Sun, 14 Dec 2025 14:05:45 +0300
Message-ID: <14364434.20251214140545@yandex.ru>
To: Marco Atzeri <marco.atzeri@gmail.com>, cygwin@cygwin.com
Subject: Re: group '545' does not exist ?
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From: Andrey Repin via Cygwin <cygwin@cygwin.com>
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Cc: Andrey Repin <anrdaemon@yandex.ru>
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Greetings, Marco Atzeri!

> On 05/12/2025 19:48, Corinna Vinschen via Cygwin wrote:

>>> Right now, our newgrp is commandline compatible with Linux' newgrp from
>>> shadow-utils:
>>>
>>> - A single '-' reinitializes the environment.
>>> - The group must be given as name, not as GID.
>>>

> Hi Corinnathe current version of newgroup is NOT doing so.
> It spins a new shell process

IIRC, that's the only way to create a new environment in Windows by an
external process.
If you take a look at the exec's implementation, it also starts a small code
to manage the spawned process.

> $ pstree
> ?─┬─?───sshd
>    ├─mintty───bash───pstree
>    └─ssh-agent

> $ newgrp - Users

> $ pstree
> ?─┬─?───sshd
>    ├─mintty───bash───bash───pstree
>    └─ssh-agent


> Noticed as it is very easy to bomb the enviroment.


-- 
With best regards,
Andrey Repin
Sunday, December 14, 2025 14:02:50

Sorry for my terrible english...

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