The read-only magic variable C<${^UNICODE}> reflects the numeric value
of this setting. This is variable is set during Perl startup and is
thereafter read-only. If you want runtime effects, use the three-arg
-open() (see L<perlfunc/open), the two-arg binmode() (see L<perlfunc/binmode>),
+open() (see L<perlfunc/open>), the two-arg binmode() (see L<perlfunc/binmode>),
and the C<open> pragma (see L<open>).
(In Perls earlier than 5.8.1 the C<-C> switch was a Win32-only switch