Re: [PATCH v7 0/3] console: Add persistent scrollback buffers for all VGA consoles

Adam Borowski
2016-11-29T10:44:20Z

On Tue, Nov 29, 2016 at 10:01:15AM +0000, Andrey Utkin wrote:
> Regarding logout scrollback clearing not working for me. ncurses-6.0-rc1
> which I tested it with is the latest available in Gentoo portage, please
> confirm whether I need any newer version, or should I tune something
> else. I'd appreciate if you also tested your patch with gentoo setup.

Could you please check whether its terminfo carries the required
definitions? In ncurses sources, that's misc/terminfo.src

The relevant parts are:
.--==
# The 3.0 kernel adds support for clearing scrollback buffer (capability E3).
# It is the same as xterm's erase-saved-lines feature.
linux3.0|linux 3.0 kernels,
E3=\E[3J, use=linux2.6,

# This is Linux console for ncurses.
linux|linux console,
use=linux3.0,
`----

I believe the first part was added first; if that's true it's possible this
will work for you:
TERM=linux3.0 clear

I'm not sure what Gentoo does to clear the console during logout: it might
just invoke "clear" (or its underlying ncurses implementation), it might
carry a copy of Debian's "clear_console"[1], it might do something else
entirely.

Meow!

[1]. It originally came from Ubuntu, forked there from "clear".
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