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Date: Wed, 12 Mar 1997 20:04:49 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199703120904.UAA22408@godzilla.zeta.org.au>
To: ache@nagual.ru, brian@awfulhak.demon.co.uk
Subject: Re: ppp & signals pending
Cc: brian@FreeBSD.ORG, current@FreeBSD.ORG
Sender: owner-current@FreeBSD.ORG
X-Loop: FreeBSD.org
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>HUP must never come during normal mode because modem is not control
>terminal for PPP. PPP code strangely use every second carrier check
>instead of using HUP on control terminals.

It's difficult to use HUP on control terminals.  Remember all the
problems slattach had getting it to work?  (slattach still doesn't
work right, mainly because too much is done in the signal handler :-).
E.g., an interactive process can't use HUP on a separate control
terminal since it needs to keep its normal control terminal and there
can only be one control terminal.

Bruce