#!/usr/bin/perl -w
use strict;

use utf8;
my $str1 = <DATA>;              # not utf8
my $str2 = eval "'".<DATA>."'"; # utf8

no utf8;
my $str3 = <DATA>;              # not utf8
my $str4 = eval "'".<DATA>."'"; # not utf8

binmode(DATA,":utf8");          # THIS is what you should do.
my $str5 = <DATA>;              # utf8 

print "str1 is",utf8::is_utf8($str1) ? "" :" not"," utf8\n";
print "str2 is",utf8::is_utf8($str2) ? "" :" not"," utf8\n";
print "str3 is",utf8::is_utf8($str3) ? "" :" not"," utf8\n";
print "str4 is",utf8::is_utf8($str4) ? "" :" not"," utf8\n";
print "str5 is",utf8::is_utf8($str5) ? "" :" not"," utf8\n";
__DATA__
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