bug#9246: Scrolling bug with word-wrap in emacs -nw

[Eli Zaretskii <eliz@gnu.org>]

> From: Antoine Levitt <antoine.levitt@gmail.com>
> Cc: riccardi.thomas@gmail.com,  9246@debbugs.gnu.org
> Date: Fri, 30 Dec 2011 15:01:26 +0100
> 
> Here's two patches. The first adds the warning from the info file into
> the variable definition. The second fixes erc-scrollbottom by using
> post-command-hook instead of window-scroll-functions.
> 
> Can you merge them?

Will do, thanks.

> >   go to window-end
> >   call posn-at-point
> >   compare the row returned by posn-at-point with window-height
> 
> That works pretty well! (when hooked into post-command-hook) Except that
> sometimes posn-at-point is nil, presumably because redisplay hasn't
> taken place yet.

If posn-at-point returns nil, it means point is outside of the
displayed portion, which in itself is something you may want to know,
I think.

> I couldn't find a post-redisplay-hook, which might be more
> appropriate. Is there one?

There's redisplay-end-trigger-functions, but it's deprecated.  Stefan
expressed the desire to have a hook you want many times in the past,
but no one stepped forward to do the job yet.