[ltp] T420 /proc/acpi/ibm/video not working

Jagged O'Neill linux-thinkpad@linux-thinkpad.org
Sun, 8 Feb 2015 20:50:46 +0100

On Sun, Feb 08, 2015 at 04:46:15PM +0000, Timothy Murphy wrote:
> On Saturday 07 February 2015 12:14:45 David Woodfall wrote:
> > commands:       lcd_enable, lcd_disable
> > commands:       crt_enable, crt_disable
> > commands:       dvi_enable, dvi_disable
> > commands:       auto_enable, auto_disable
> > commands:       video_switch, expand_toggle
> I get the same output on my T520 under Fedora-21/KDE
> in /proc/acpi/ibm/video.
> But I have no idea what it means.
> How does one give the command lcd_enable, for example,
> and what effect does it have?

You echo those commands into the very same file. See
(some lines above the middle of the document).

Don't know if it's worth it, however. When I use an external display
with my TP, I prefer to let xrandr manage them.


valgrind python -c 'for i in range(1,1): print(i)' 2>&1 | grep error