unsetopt [ {+|-}options | {+|-}o option name ] [ name ...
       ]
       Unset the options for the shell.  All options spec-
       ified  either  with flags or by name are unset.  If
       no arguments are supplied, the names of all options
       currently  unset  are  printed.   If the -m flag is
       given the arguments are taken  as  patterns  (which
       should be quoted to preserve them from being inter-
       preted as glob  patterns),  and  all  options  with
       names matching these patterns are unset.
