my $file="simple.txt";
open(FILE, "<:utf8", $file) or die "can not open $file";
my @data1 = <FILE>;
close(FILE);

use open ':encoding(utf8)';
open(FILE, $file) or die "can not open $file";
my @data2= <FILE>;
close(FILE);

die "different size" if (scalar(@data1) != scalar(@data2));
while (@data1) {
  my $s1 = shift(@data1);
  my $s2 = shift(@data2);
#  print "1: $s1\n2: $s2\n";
  die "different data" if ($s1 ne $s2);
}

##</code><code>##

utf8 "\xD0" does not map to Unicode at ./essai.pl line 8, <FILE> line 1.
different data at ./essai.pl line 21.