Scrolling: This must be a bug!

[Lars Hansen]

Hi!

This must be a bug!

When a scroll a window by hold down the the down-arrow button,
the scrolling motion have anoying jumps now and then. What happes
is, obviously, that the window gets recentered. I have tried (nearly)
any combination of settings of variables in the customization group
"windows", but nothing helps.

Today I have tried the following:
Set scroll-margin to eg. 5. Press the down-key repeatedly (but slowly
so you can see what happens). Then the window is supposed to scroll
so that there are 5 rows from the cursor to the bottom of the window.
But now and then there is no scroll, so that there is only 4 lines from
the cursor to the bottom of the window! The next press of the down-key
brings things back to normal. There are no long lines in the file, and
and the behavoiur does not seem to be conneted to any specific points
in a file.

The problem occurs in

GNU Emacs 21.2.1 (i386-msvc-windows98.3000) of 2002-03-19 on buffy

on a PC running MS Windows ME, but it was there also when I used GNU Emacs
20.7 and MS Windows 95. I do *NOT* have the problem with

GNU Emacs 20.7.4 (alphaev56-dec-osf4.0d, X toolkit) of Wed Feb 28 2001 on
gram

under suse linux, so I suppose it is i bug in the MS Windows specific code.

Best regards, Lars Hansen <larsh@math.ku.dk>