Looking at the source (utf8.c)
Come on. perluniprops. 
binmode STDOUT, ':encoding(utf-8)';

my $arg = "\x{10FFFF}"; # for instance

# simpler way?
$arg =~ s/\p{NChar}/\x{FFFD}/; # replacement char

print $arg, "\n";

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In reply to Re: catching Unicode non-character ... illegal for open interchange by Anonymous Monk
in thread catching Unicode non-character ... illegal for open interchange by karlberry

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