Re: [gentoo-user] Console scrollback

[Alan Mackenzie <acm@muc.de>]

Hello, Wol.

On Thu, Jan 21, 2021 at 09:32:13 +0000, Wols Lists wrote:
> On 20/01/21 19:59, Alan Mackenzie wrote:
> > I can understand the kernel maintainers not being enthusiastic about
> > the existing code.  But that dates from, I believe, the 1990s, when
> > RAM was measured in megabytes, and processor speeds in megahertz.
> > Optimisation for speed and store usage just isn't important any more.

> I think you're being highly optimistic. Bear in mind that this is the
> code that was responsible for Alan Cox ceasing linux development, it's
> such a pile of steaming manure ...

It is indeed a tortuous mess of code, with far too many abstractions, and
far too little overview.

> Don't ask me why it is, but I think it's got so much stuff wrong with it
> that the entire system is marked "beware here be dragons".

Over the weekend, I achieved the first part of my task, getting a
transparent new driver into the kernel, which would merely pass through
to and from /dev/sctty3 to and from /dev/tty3, etc.  This works.

Now I have to hook up with the /dev/vcs drivers to buffer the text
written to the screen, so as to be able to output it again in the event
of a <Ctrl>-<PageUp/Down>.

I would guess I'm around 50% through the task (as in the first 50% takes
the first 90% of the time, and the second 50% takes the second 90% of the
time).

> https://lwn.net/Articles/842415/

> Take a read, as it's mentioned in this article.

The website said it would become freely available on 2021-01-28, so I'll
read it then.

> Cheers,
> Wol

-- 
Alan Mackenzie (Nuremberg, Germany).