I think I may have figured out how to do things from the virtual terminals to affect the X screen.
The vt for X is 6 so we can do:
chvt 6 to switch to the virtual terminal 6
Next we need to have a little delay, so let's add sleep 4 (you can also use 2 if you think that's a bit faster)
We also need to add "export DISPLAY=:0" to set the X display.
Then to change the user, we use "sudo -u knoppix "
So to do xrandr and change the resolution: (this is pretty useful when you mess around with screen resolutions that cause a blank screen)
Hit CTRL+ALT+F4 to switch to VT 4: then type
chvt 6; sleep 4; export DISPLAY=:0; sudo -u knoppix xrandr
chvt 6; sleep 4; export DISPLAY=:0; sudo -u knoppix xrandr --output HDMI-1 --mode 800x600
To launch terminator:
chvt 6; sleep 4; export DISPLAY=:0; sudo -u knoppix terminator &
To open the main menu:
chvt 6; sleep 4; export DISPLAY=:0; sudo -u knoppix lxpanelctl menu
Professionally restored & fully recapped Commodore 64 computer | NTSC C64
$299.00
Vintage Commodore 1702 Computer Gaming Monitor – CLEAN
$399.99
Commodore Floppy Disk Drive Model 1541 W/ Box - Powers On - G3
$19.99
Commodore 1541-II Floppy Disk Drive 5.25 C64 with Power Supply (Works)
$125.00
Commodore 128 Computer, Fully Cleaned And New Capacitors, Good Keyboard, Box
$499.00
Vintage Commodore 64 Computer With Power Supply,cabels , Powers On User Guide
$110.00
Commodore 128 Computer With Power Supply, Box, Manuals, 1571, 1541, Untested
$450.00
Vintage Commodore VIC 20 Computer Untested No Power Adapter MADE IN USA Keyboard
$59.99
TeensyROM Cartridge for Commodore 64/128: MIDI, Fastload, Emulation, and Network
$65.00
RARE Commodore KS64C Personal Computer Keyboard #’d 292/500 - Great Condition
$299.99