scroll-conservatively but still cursor *sometimes* still jumps off bottom

[Chris Seberino]

I want up and down arrow keys to advance by 1 line so I added this
to .emacs...

(setq scroll-conservatively most-positive-fixnum)

I noticed that when moving down through big files, *sometimes* the
cursor will jump from bottom of screen to middle.

Any idea why this would happen only some of the time?

cs

[Juanma Barranquero]

> I noticed that when moving down through big files, *sometimes* the
> cursor will jump from bottom of screen to middle.
>
> Any idea why this would happen only some of the time?

Because Emacs' redisplay is unable to keep with the scrolling. Before
23.1, with scroll-conservatively set to a large value, Emacs never
jumped; now it tries no to do it, but sometimes it fails. I think the
relevant ChangeLog entry is this one:

2008-10-27 Chong Yidong <c...@stupidchicken.com>

* xdisp.c (try_scrolling): When computing the distance from the
scroll margin to PT, try moving some distance past the window
bottom before giving up.

Juanma

[Chris Seberino]

On Dec 12, 10:08 am, Juanma Barranquero <lek...@gmail.com> wrote:

> Because Emacs' redisplay is unable to keep with the scrolling.

Juanma

Thanks! Does the latest version fix this problem? Is there another
fix? Or, do we all just have to wait until it gets fixed in future?

cs

[Juanma Barranquero]

> Thanks!  Does the latest version fix this problem?  Is there another
> fix?  Or, do we all just have to wait until it gets fixed in future?

I don't think it is currently considered a bug, but you're free to
report one with M-x report-emacs-bug :-)

Juanma