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From: chris@umcp-cs.UUCP (Chris Torek)
Newsgroups: net.unix-wizards
Subject: Re: TTY Inquiry
Message-ID: <1834@umcp-cs.UUCP>
Date: Sun, 13-Oct-85 10:41:04 EDT
Article-I.D.: umcp-cs.1834
Posted: Sun Oct 13 10:41:04 1985
Date-Received: Tue, 15-Oct-85 05:51:52 EDT
References: <482@scirtp.UUCP> <5647@fortune.UUCP>
Distribution: net
Organization: U of Maryland, Computer Science Dept., College Park, MD
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> One approach that can be taken to allow bi-directional use
> of tty lines is to have 2 minor #'s for each physical port.

We use two major device numbers, but the basic idea is the same.

> ...  attempts to open the other mode fail with EBUSY.

Personally, I think that our approach (making normal `incoming'
opens simply suspend until the outgoing call has completed) is
better.

> The changes that need to made are relatively minor (but are
> unfortunately proprietary code, so I can't post them).

But I can post ours, and I have done so in the past.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 4251)
UUCP:	seismo!umcp-cs!chris
CSNet:	chris@umcp-cs		ARPA:	chris@mimsy.umd.edu