1unsetopt [ {+|-}options | {+|-}o option name ] [ name ... ] 2 - 3 Unset the options for the shell. All options specified either 4 with flags or by name are unset. If no arguments are supplied, 5 the names of all options currently unset are printed. If the -m 6 flag is given the arguments are taken as patterns (which should 7 be quoted to preserve them from being interpreted as glob pat- 8 terns), and all options with names matching these patterns are 9 unset. 10