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From: thurlow@convex.com (Robert Thurlow)
Newsgroups: comp.windows.x
Subject: Re: how does xterm tell vi the window size
Keywords: xterm vi
Message-ID: <1989@convex.UUCP>
Date: 8 Oct 89 16:57:42 GMT
References: <253@zeek.UUCP> <1227@virtech.UUCP> <286@enuxha.eas.asu.edu> <1233@virtech.UUCP> <1055@acorn.co.uk>
Sender: news@convex.UUCP
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john@acorn.co.uk (John Bowler) writes:
>	2) If the number of columns or lines is still not known, use
>		BSD specific ioctl's to attempt to find the column and
>		line values from the *new* tty driver.  If the old tty
>		driver is being used this fails, if not, and the columns
>		and lines values are non-zero use these.  (See tty(4) on
>		a BSD system).  Since pre-R4 System V systems only have
>		the old (version 7) tty driver this mechanism can't
>		be used on System V (until release 4).

Um, just a nit, but I remember a major change to the AT&T 'tty' driver
between System III and System V Release 1.  It made a big difference to
the performance of our Zilog Z8000, and I think I remember the release
notes making some comments.  And the 'termio' structure came along in
there somewhere as well, changing the ioctl()'s completely from 'sgtty'
days.  How much heritage does the Sys V driver have with version 7?

Rob T
--
Rob Thurlow - Expatriate Canadian                      thurlow@convex.com
"From the heart of 'The Friendship State'"