clear scrollback buffer of Linux Virtual Console Terminals

Question

I'd like to clear the scrollback buffer on Linux console VTs programmatically. i.e. not just clear the current visible screen, but the entire scrollback buffer, too. I.e. everything that after a clear screen would still be visible with Alt-PgUp should be gone too. Anybody got an idea how to achieve that in nice code?

Answer 1

I don't think this is in mainline yet, but linux-next has a patch to support a new console escape sequence that clears the screen and the scrollback buffer: CSI 3 J

For something that works without having to upgrade your kernel, you can use:

chvt 42; chvt <current tty no>; echo -en "\e[1;1H\e[2J"

Alternatively:

echo -e "\e[12;42]"; sleep .01; echo -en "\e[12;<current tty no>]\e[1;1H\e[2J"

You can get the current tty number with:

$( ls -l /proc/self/fd | sed -ne 's/.*tty//p' )