From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <7871fcf50612201654u2bf12d6j7a8291991e4ef991@mail.gmail.com>
Date: Wed, 20 Dec 2006 19:54:58 -0500
From: "Joel Salomon" <joelcsalomon@gmail.com>
To: "Fans of the OS Plan 9 from Bell Labs" <9fans@cse.psu.edu>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Subject: [9fans] Implementing cooked mode
Topicbox-Message-UUID: f6d1d5fa-ead1-11e9-9d60-3106f5b1d025

If a program has the console in raw mode, can it erase characters or
words that it has echoed to the screen?

Context is a homework assignment to implement cooked mode in user
space.  The code in /sys/src/cmd/rio/wind.c looks to be a start, but I
don't see how to remove characters from the screen.  I suppose I could
use string() in libdraw and draw the string graphically rather than
echoing.  Rio's wind.c and acme's text.c both handle the various
control characters, but they aren't pretending to write to the
console.

Nemo's book has a similar assignment, so it seems to be doable; I just
haven't found how in the manual.

Failing that, are there printable glyphs shown if control characters
are write()n to the console?

--Joel