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Mail Archives: djgpp-workers/1998/12/29/03:25:24

Date: Tue, 29 Dec 1998 10:25:24 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender: eliz AT is
To: Kbwms AT aol DOT com
cc: djgpp-workers AT delorie DOT com
Subject: Re: info fails to clear the screen
In-Reply-To: <d643f859.3687fb45@aol.com>
Message-ID: <Pine.SUN.3.91.981229102447.15836S-100000@is>
MIME-Version: 1.0
Reply-To: djgpp-workers AT delorie DOT com

On Mon, 28 Dec 1998 Kbwms AT aol DOT com wrote:

> I notice that info (from txi312b of 16 Sep 98) fails to clear the screen
> upon exit.

Info doesn't clear the screen on purpose.  The screen is cleared as a
side effect of changing the screen dimensions (i.e., the number of
rows or columns displayed on the screen).  That's how the BIOS
functions used by Info work.  Info actually tries to avoid clearing
the screen, by not switching the video mode unless it has to.  (I find
this behavior justified because sometimes you would like the
information be still on screen for you to be able to read it when you
do whatever you needed to invoke Info for.)

The above means that if Info uses the same screen dimensions as those
you usually run your system, the screen will not be cleared.  For
example, if your monitor is in the default 80x25 mode, and Info is not
instructed to switch to other dimensions once it starts, the screen
will not be cleared upon exit.

The default setup of Info is to switch to 80x40 display, because
DJGPP.ENV has this snippet in the [info] section:

  +INFO_LINES=40

However, if you have edited this line, or renamed info.exe into
something else, or set INFO_LINES in the environment to a different
value, you might have a situation where the screen dimensions inside
and outside of Info are identical, and then the screen is not cleared
on exit.

Is this behavior a problem?

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