:x is a vim feature, so this wouldn't support it, so you'll have to use :wq instead.
Incorrect.
:x is a vi feature, that was introduced by Mary Ann Horton to actual Joy+Horton vi in February 1980.
* https://code.illumos.org/plugins/gitiles/illumos-gate/+/refs...
Ritter's vi is derived from Joy+Horton vi. Illumos has the original.
or ZZ to save and exit
Incorrect.
:x is a vi feature, that was introduced by Mary Ann Horton to actual Joy+Horton vi in February 1980.
* https://code.illumos.org/plugins/gitiles/illumos-gate/+/refs...
Ritter's vi is derived from Joy+Horton vi. Illumos has the original.