Slackware Linux: xrandroid uses two screens

1. view the monitor: xrandroid

LVDS connected 1366X768 + 0 + 0 (normal left inverted right X axis Y axis) 309mm x 173mm
1366X768 60.0 * +
1360X768 60.0
1280x768 60.0
1280x720 60.0
1024x768 60.0
1024x600 60.0
800x600 60.0
800x480 60.0
640x480 60.0
Crt1 connected (normal left inverted right X axis Y axis)
1360x768 59.7 +
1280x800 59.8
1280x768 59.8
1280x720 60.0
1024x768 75.0 70.1 60.0
1024x600 75.0 70.1 60.0
800x600 72.2 75.0 60.3
800x480 72.2 75.0 60.3
640x480 75.0 72.8 59.9

2. Enable the second monitor to work:

CRT1 is the new monitor. After all, the laptop screen is small and uncomfortable.

Xrandroid -- output CRT1 -- auto

At this time, the second monitor started to work. The display content is the same as that of the notebook. Now, use the notebook shortcut key to turn off the screen (do not use xrandroid to close the screen, so as to avoid some accidents and troubles)

If you want other effects, check man's manual...