Is there a way to tell an existing process to change what X server it should be using?
Não que eu saiba, no X. No entanto, existem dois aplicativos, Xpra e NX , que foram projetados para permitir exatamente isso.
Por exemplo, o Xpra afirma:
Xpra is 'screen for X', and more: it allows you to run X programs, usually on a remote host and direct their display to your local machine. It also allows you to display existing desktop sessions remotely. Xpra is "rootless" or "seamless", and sessions can be accessed over SSH, or password protected and encrypted over plain TCP sockets. Xpra adapts to bandwidth constraints and is fully open-source.
Da mesma forma, os caras da NoMachine, os criadores do NX, afirmam:
It is the perfect answer to those looking for a solution able to create hundreds of hosted Linux desktops, easy to manage and secure. NoMachine Terminal Server doesn't suffer from all the limitations that affect the traditional X-Window based solutions. Your desktop continues to live while it is disconnected, devices shared on the server follow you wherever you go and speed is spectacular even over the most modest network link, so fast to be unbeaten by any similar product designed for any operating system, not only Linux.
Ambos os produtos existem para todos os principais sistemas operacionais, Windows, MacOS, Linux.