How to use Xfce4-display-settings terminal commands?

What I want is a terminal command that would activate internal display in case it is de-activated in Xfce. (Then, I could run this command by a script+shortkey and get a solution to this problem). The help of Xfce4-display-settings gives this

~ $ xfce4-display-settings -h
Usage:
  xfce4-display-settings [OPTION...]

Help Options:
  -h, --help                    Show help options
  --help-all                    Show all help options
  --help-gtk                    Show GTK+ Options

Application Options:
  -s, --socket-id=SOCKET ID     Settings manager socket
  -v, --version                 Version information
  -m, --minimal                 Minimal interface to set up an external output
  --display=DISPLAY             X display to use

I am interested in this: --display=DISPLAY X display to use

I guess it means that the command xfce4-display-settings --display=DISPLAY would activate the given DISPLAY.

What to enter there in place of DISPLAY that would be the internal display?

What for the external display?

Solution 1:

The --display option to xfce4-display-settings will I assume take an X screen (as per the environment variable $DISPLAY, eg :0.0).

This is unlikely to be useful to you - multiple monitors are treated as a single large X screen, with the xinerama X extension providing hints on the actual monitor boundaries to window managers so that, eg maximising a window will maximise it to fill only one monitor.

This option is useful if you are running multiple thin clients off a single machine, or using X over SSH (in which case your $DISPLAY will look something like remotehost:7.0).