#!/usr/bin/perl -w -CO

use strict;
use utf8;
use CGI qw/:standard/;

my $URLRAWDATA = "";
if ($ENV{'REQUEST_METHOD'} eq "POST") {
   read(STDIN, $URLRAWDATA, $ENV{'CONTENT_LENGTH'});
}
else {
   $URLRAWDATA = $ENV{'QUERY_STRING'};
}
my %URLDATA;
my @data = split (/&/, $URLRAWDATA);
for (@data) {
   my ($key, $value) = split /=/;
   $value =~ s/%0D%0A/<\|br\|>/g;
   $value =~ tr/+/ /;
   $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
   $URLDATA{$key} = $value;
}

print "Content-type: text/html\n\n";
print "äöü ";   # richtige Umlaute: äöü
print $URLDATA{'name'}; # fehlerhafte Umlaute: äöü

print "Content-Type: text/html; charset=utf-8\n\n";

use CGI;
my $q = CGI->new;
$q->charset('UTF-8');

print $q->header();

print $q->param('name');

use CGI;
use Encode qw(decode_utf8);
my $q = CGI->new;
$q->charset('UTF-8');

print $q->header();

my $name = decode_utf($q->param('name'))
print $name;

binmode STDOUT, ':encoding(UTF-8)';
binmode STDIN,  ':encoding(UTF-8)';

#!/usr/bin/perl -w

use strict;
use utf8;
use CGI;
use Encode qw(decode_utf8);

binmode STDOUT, ':encoding(UTF-8)';
binmode STDIN,  ':encoding(UTF-8)';

my $q = CGI->new;
$q->charset('UTF-8');
print $q->header();

print "äöü";
print decode_utf8($q->param('name'));