There is a difference between ZZ and :wq! ZZ will NOT force a write on a
read only file :wq! will.
Also be careful with ZZ if you inadvertently press Control ZZ you will
have stopped jobs.
NOTE: All tips provided are USE AT YOUR OWN RISK. Tips are submitted
by various unix admins around the globe. UGU suggest you read and
test each tip in a non-volitile environment before placing into
production.