my $arg = $ENV{PATH}; # a tainted value
use constant UTF8 => "\x{1234}";
-sub is_utf8 {
- my $s = shift;
- return 0xB6 != unpack('C', chr(0xB6).$s);
-}
+*is_utf8 = \&utf8::is_utf8;
for my $ary ([ascii => 'perl'], [latin1 => "\xB6"], [utf8 => "\x{100}"]) {
my $encode = $ary->[0];