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	Mon, 15 Sep 1997 12:27:20 +0930 (CST)
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Date: Mon, 15 Sep 1997 12:27:20 +0930
From: Greg Lehey <grog@lemis.com>
To: Terry Lambert <tlambert@primenet.com>
Cc: brian@awfulhak.org, jkh@time.cdrom.com, hackers@FreeBSD.ORG
Subject: Re: Here's an interesting bug in our utmp handling.
References: <19970915121733.25438@lemis.com> <199709150255.TAA13144@usr09.primenet.com>
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In-Reply-To: <199709150255.TAA13144@usr09.primenet.com>; from Terry Lambert on Mon, Sep 15, 1997 at 02:55:01AM +0000
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On Mon, Sep 15, 1997 at 02:55:01AM +0000, Terry Lambert wrote:
>>>>> I don't understand why login should ever be called interactively.  We
>>>>> have su for that.
>>>>
>>>> Perhaps 0500 permissions are in order.
>>>
>>> Ugh.  Why not make it work as documented, instead?
>>
>> Because it requires changing every shell.  Most are ports.
>
> In exec, revoke the tty to kill off all the other processes, if
> it's /bin/login, while keeping the tty for the process exec'ing
> so it doesn't hang up.

Hmm.  What if the old user had left some things running in the
background?

> The original reason for this was to let you actually re-login;
> it is useful for dialup connections, which would otherwise cause
> you to have to reestablish the call.  Consider phone networks
> with higher charges for call teardown and reestablishing a call than
> the charges you'd pay for remaining online.  Most long distance
> calls fall into this category, even in the US.

'exec su' would do the same thing.

Greg