[NCLUG] xrandr

[Jeff Moe]

On 11/04/2013 04:28 PM, Kerry Miller wrote:
> Hi Group,
>
> I have read the man page.  It is NOT obvious to me how to use xrandr 
> to cause an image to appear on both the lap top monitor and on the 
> projector svga port at the same time.  More explicit detail please.

There are a couple ok GUIs for xrandr (at least in Debian). I prefer 
arandr, but there is also lxrandr (from memory).

Here is what we use to do a *different* screen on both monitors (double 
wide):

xrandr --output HDMI1 --mode 1920x1080 --pos 1920x0 --rotate normal 
--output DP1 --off --output eDP1 --mode 1920x1080 --pos 0x0 --rotate 
normal --output VGA1 --off


I think instead of --pos, you can use something like: --same-as. So as 
an untested guess, perhaps something like:

xrandr --output HDMI1 --mode 1920x1080 --rotate normal --output DP1 
--off --output eDP1 --same-as --mode 1920x1080  --rotate normal --output 
VGA1 --off

Or perhaps for your ports, something along the lines of:
xrandr --output VGA1 --mode 1024x768 --rotate normal --output VGA2 
--same-as --mode 1024x768  --rotate normal

If you run `xrandr` without any options, it will list what modes and 
outputs you have available.

Perhaps that will help a bit. :)

-Jeff