Linux console scrollback [ Was: Allowing point to be outside the window? ]

[Alan Mackenzie]

Hello, Juri.

On Wed, Dec 08, 2021 at 21:56:47 +0200, Juri Linkov wrote:
> > I briefly tested with two contemporary editors (Atom and VS Code), and
> > their behavior indeed differs between mouse-based and keyboard-based
> > scrolling: in the former case (scrolling via mouse), the cursor stays
> > put and moves out of view, while in the latter case (scrolling via the
> > PgDn key), the cursor changes position to stay on screen.

> Linux console supported keyboard-based scrolling with
> Shift-PageDown/PageUp where the cursor stays on the command line and it
> scrolls back on a key press, but recently this feature was removed.

Just as a matter of interest, I've hacked the Linux sources to put this
essential feature back again, in an improved fashion.  Where previously
one scrollback buffer was shared by all the tty's, causing the
scrollback to be lost on moving to a different tty, now each tty has its
own buffer which does not lose its contents by such a move.

I've published the patch on the Gentoo user's list.  It is slightly
different for different kernel major versions.

If anybody is interested in this patch, and can't be bothered to dig it
out of the Gentoo list archive, feel free to send me an email, and I will
reply with the patch and (short) directions for its use.

-- 
Alan Mackenzie (Nuremberg, Germany).