[comp.sources.bugs] screen emulation bug

nelson@sun.soe.clarkson.edu (Russ Nelson) (03/19/89)

The following uuencoded typescript is a bit of output for an ANSI
X3.64 terminal.  It was produced by Gnu Emacs running GNUS.  If you
have an ANSI terminal (or VT-100), you can cat the file and see that
all the numbers on the left hand margin line up.  I am using a PC with
NANSI, and they line up for me.  If you run screen and try the same
thing, you'll see that the numbers don't line up.

I have tracked the problem down to CursorRight, which refuses to move
the cursor to the right if a character has been printed in the
rightmost position (causing a wrap).  In other words, screen thinks
that CursorRight won't cause a wrap.

Perhaps someone can explain to me why screen insists on repositioning
the cursor to the right hand column after a wrap has occurred?
-russ

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++2TM+1M;,3LX2`I3S
``
end
-- 
--russ (nelson@clutx [.bitnet | .clarkson.edu])
If you can, help others.
If you can't, at least don't hurt others--the Dalai Lama

net@tub.UUCP (Oliver Laumann) (03/21/89)

In article <2690@sun.soe.clarkson.edu> nelson@clutx.clarkson.edu writes:
> I have tracked the problem down to CursorRight, which refuses to move
> the cursor to the right if a character has been printed in the
> rightmost position (causing a wrap).  In other words, screen thinks
> that CursorRight won't cause a wrap.

This is a feature of the VT100 (and descendants such as VT220 and
VT320); try it out in local mode.  Since my ANSI X3.64 document has
vanished from my desk, I can't look what the standard says about this.

Regards,
--
Oliver Laumann              net@TUB.BITNET              net@tub.UUCP