clean up kernel_{read,write} & friends v2

[Nicolas Pitre]

On Fri, 5 Jun 2020, Philippe Mathieu-Daudé wrote:

> Unfortunately refreshable braille displays have that "hardware
> limitations". 80 cells displays are very expensive.
> Visual impairments is rarely a "choice".
> Relaxing the 80-char limit make it harder for blind developers
> to contribute.

Well, not really.

It is true that 80-cells displays are awfully expensive. IMHO they are 
also unwieldy due to their size: they are hardly portable, and they 
require your hands to move twice as far which may sometimes impair 
reading efficiency. So I never liked them.

My braille display has 40 cells only. So even with a 80-cells limit I 
always had to pan the display to see the whole line anyway.

My text console is set to 160x128. The trick here is to have the number 
of columns be a multiple of the braille display's width to avoid dead 
areas when panning to the right.

So if you ask me, I'm not against relaxing the 80 columns limit for 
code. What really matters to me is that I can stay clear of any GUI.


Nicolas