x11vnc is wonderful but the only problem i have is when every i get off of it from my PC it shuts down in my N900,

i want to know a way on how to keep the process alive say if it dies i would want to keep it restart just like a service when killed it should be restarted how do i do it?
a shell script
or a python script thats always running and checks if the process is killed it started x11vnc again not sure
how do i do it using shell script?

Thanks a Lot in advance!