The show command shows their settings; show all shows all the settings.
Options changed using set can be returned to the default state by giving the
corresponding unset command. See also the reset (p. ) command, which returns
all settable parameters to default values.
If a variable contains time/date data, show will display it according to
the format currently defined by set timefmt, even if that was not in effect
when the variable was initially defined.
The set and unset commands may optionally contain an iteration clause.
See iteration (p. ).