[comp.emacs] GNU 18.52 redisplay problem

bill@hpcvlx.HP.COM (Bill Frolik) (03/24/89)

Has anyone else out there seen the problem I'm seeing in GNU Emacs 18.52?
Put the cursor at the start of a line of text, and have a fairly long line
of text on the line immediately above it.  Now do something like, say, a
kill-line.  The text on the current line disappears, as it should, but then
the last 9 characters of the previous line get replicated at the start of
the line I just wiped out, and the cursor and everything else get bumped
down one line.  For example:


Before:		This is a long line of text to show what might happen.
		_Cursor is here, this line will get killed.
		Other text follows.


After:		This is a long line of text to show what might happen.
		t happen.
		_
		Other text follows.


Sometimes I see this with other functions, too.  Like, in the "before" case,
when the cursor is where I've indicated, maybe all I need to do is insert
a tab; everything drops down a line and the tail end of the previous line
appears.

If I do a ^L the ghost line disappears, and everything is fine.  This problem
doesn't happen all the time, I haven't pinned down exact circumstances to 
guarantee it will happen.  Have I got some variable set wrong, is it pilot
error, or is there a bug in the redisplay code?

I'm running GNU Emacs 18.52 under SCO's 386 XENIX on an HP Vectra RS/25C.

________________________________________

Bill Frolik	Hewlett-Packard Co
hp-pcd!bill	Corvallis, Oregon

shirono@hcx3.SSD.HARRIS.COM (04/02/89)

**> comp.emacs  bill@hpcvlx.HP.COM  Mara 23, 1989 <**
> Put the cursor at the start of a line of text, and have a fairly long line
> of text on the line immediately above it.  Now do something like, say, a
> kill-line.  The text on the current line disappears, as it should, but then
> the last 9 characters of the previous line get replicated at the start of
> the line I just wiped out, and the cursor and everything else get bumped
> down one line.  For example:

			**> Example deleted <**

> Sometimes I see this with other functions, too.  Like, in the "before" case,
> when the cursor is where I've indicated, maybe all I need to do is insert
> a tab; everything drops down a line and the tail end of the previous line
> appears.

Yup, sounds familiar.  I've been experiencing the same problem for some
time, but used to attribute it to other factors:

	- (*&)$#(&# terminal
	  I used to have a Wyse 50.  I really hated it, and couldn't wait
	  'til I got my hands on a 95.  Well I finally did.

	- Windowing system
	  In-house, we use a CRT windowing program that we got from I don't
	  know where, and I thought that maybe the windowing program was
	  the one acting up with my text.  Also, at times I thought that
	  perhaps the program generating those funny terminfo files was the
	  one acting up.

Now that somebody else has mentioned it, I am disabused of my
misperceptions.  Perhaps there is a bug in the display code; I don't know.

--Roberto
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