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Date: Sat, 3 Oct 2015 23:08:57 +0200
From: Jilles Tjoelker <jilles@stack.nl>
To: Bryan Drewery <bdrewery@FreeBSD.org>
Cc: freebsd-arch@FreeBSD.org
Subject: Re: login -f changing session getlogin(2)
Message-ID: <20151003210857.GA57303@stack.nl>
References: <560D826D.7000302@FreeBSD.org> <20151001203436.GA22737@stack.nl>
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On Thu, Oct 01, 2015 at 03:02:21PM -0700, Bryan Drewery wrote:
> Can't we use something like forkpty(3) for the child to avoid the issues
> you mention? It calls setsid(2) via login_tty(3).

This would make sense for a special impersonation tool or for a paranoid
version of su, but not for a normal login.

You can do this right now using script(1), for example
  script /dev/null login -f SOMEUSER

-- 
Jilles Tjoelker