x11vnc

A VNC server that will enable VNC on an existing display server. By default, the server will automatically terminate once all clients disconnect from it. More information: https://manned.org/x11vnc.

• Launch a VNC server that allows multiple clients to connect:
  x11vnc -shared
• Launch a VNC server in view-only mode, and which won't terminate once the last client disconnects:
  x11vnc -forever -viewonly
• Launch a VNC server on a specific display and screen (both starting at index zero):
  x11vnc -display :{{display}}.{{screen}}
• Launch a VNC server on the third display's default screen:
  x11vnc -display :{{2}}
• Launch a VNC server on the first display's second screen:
  x11vnc -display :{{0}}.{{1}}