I suspect the problem happens when the cursor moves to the modeline. When
you do the page-up and page-down, at some point you will notice the cursor
on the mode line. After that, you will see the minibuffer height increase
and the garbling starts.

To me, it appears like the count of lines/rows in the frame during the
scrolling is off by 1. This has a domino effect on subsequent page up and
down and ends up messing the modeline and the menubar.

Well, this is just a hypothesis based on observation.

-dhruva


On Sat, Aug 9, 2014 at 2:14 PM, dhruva <dhruvakm@gmail.com> wrote:

> I agree. Once you reproduce the problem with the first approach, the
> second flow reproduces it again. I am suspecting if we are somehow
> corrupting the tty.
>
> I am happy that you could reproduce it. Give me some pointers and I will
> debug. By the way, it has been a long (almost 5 years) since I started
> following emacs-devel closely.
> Nice to see the same familiar hackers hacking away on emacs.
>
> with best regards,
> dhruva
>
>
> On Sat, Aug 9, 2014 at 12:06 PM, Eli Zaretskii <eliz@gnu.org> wrote:
>
>> > Date: Sat, 9 Aug 2014 10:03:17 -0700
>> > From: dhruva <dhruvakm@gmail.com>
>> >
>> > I found an easier way to reproduce the problem.
>> >
>> > - Run emacs in terminal (-nw) mode: emacs -q -nw
>> > - M-x to enger minibuffer prompt
>> > - Type 'ho' and hit TAB
>> > - CTRL-g will quit the command but the menubar is gone and the
>> minibuffer
>> > frame is multiple lines high
>>
>> This doesn't reproduce the problem for me (your previous recipe did).
>>
>
>