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Path: utzoo!linus!decvax!harpo!eagle!mhuxl!ihnp4!fortune!norskog
From: norskog@fortune.UUCP
Newsgroups: net.wanted
Subject: Re: un-dedicating a line to a dialer, an - (nf)
Message-ID: <2070@fortune.UUCP>
Date: Tue, 20-Dec-83 23:07:31 EST
Article-I.D.: fortune.2070
Posted: Tue Dec 20 23:07:31 1983
Date-Received: Thu, 22-Dec-83 01:12:28 EST
Sender: notes@fortune.UUCP
Organization: Fortune Systems, Redwood City, CA
Lines: 20

#R:denelcor:-25000:fortune:12300009:000:561
fortune!norskog    Dec 20 18:53:00 1983

It doesn't have to be in the kernel.  

Someone on the net awhile back stated that they had done it thusly:
The execute bit on tty files is not used for anything essential.
Hack init so that it will accept a signal whose meaning is:
"If the execute bit on any tty is on, disable logins on that tty"
and conversely,
"If the execute bit is off, enable logins".
and hack 'cu' & 'uuxqt' to twiddle the execute bit
and signal 'init' when they want to use that tty.

		Lance Norskog
		Fortune Systems
		{hpda,harpo,sri-unix,amd70,ihnp4,allegra}!fortune!norskog