While most people know ex commands
only by their use within vi, the
editor exists also as a separate program and can be invoked from the
shell (for instance, to edit files as part of a script).
Within ex, you can enter the
vi or visual command to start
vi.
Similarly, within vi, you can enter
Q to quit the
vi editor and enter
ex.
If you invoke ex as a standalone
editor, you can include the following options: