1unset [ -fmv ] name ...
2       Each  named  parameter  is unset.  Local parameters remain local
3       even if unset; they appear unset within scope, but the  previous
4       value will still reappear when the scope ends.
5
6       Individual elements of associative array parameters may be unset
7       by using subscript syntax on name, which should  be  quoted  (or
8       the  entire  command  prefixed  with noglob) to protect the sub-
9       script from filename generation.
10
11       If the -m flag is specified the arguments are taken as  patterns
12       (should  be  quoted)  and all parameters with matching names are
13       unset.  Note that this cannot be used when unsetting associative
14       array  elements, as the subscript will be treated as part of the
15       pattern.
16
17       The -v flag specifies that name refers to  parameters.  This  is
18       the default behaviour.
19
20       unset -f is equivalent to unfunction.
21