通过IO :: Socket :: INET连接到MPD的麻烦

Question

我正在尝试使用IO :: Socket :: INET从MPD守护程序获取有关当前轨道的信息，但是，无论请求如何，我总是获得 OK MPD版本。

#!/usr/bin/perl -w
use strict;
use feature 'switch';
use YAML qw(LoadFile Dump);
use IO::Socket::INET;

$| = 1;
my @params = ('mpd_host', 'mpd_port', 'mpd_password');

sub get_config_file
{
    my @configpaths = (
        "config.yml",
#       "$ENV{'HOME'}/.config/mpdtweet/config.yml",
    );
    for (@configpaths) {
        return $_ if -e $_;
    }
}

sub load_conf
{
    my $config = YAML::LoadFile($_[0])
        or return 1;
    my %configuration = %$config;
    return %configuration;
}

sub check_conf
{
    my @missingparams;
    for ($_[0]) {
        push(@missingparams, $_) unless $_[0]{$_};
    }
    return 0 if $#missingparams eq 0 or return @missingparams;
}

sub first_run
{
    sub sure
    {
        print "Would you like to start the first run wizard? [y/n] ";
        chomp (my $choice = <STDIN>);
        given ($choice) {
            when (/n/) {
                exit 0;
            }
            when (/y/) {
                print "I need some informations about how to connect to MPD.\n";
                &make_sample_config(&request_mpd_informations);
                print "Configuration finished!\n";
            }
            default {
                print "$choice is not a valid answer.\n"; &sure;
            }
        }
    }
    &sure;
}

sub request_mpd_informations
{
    sub request_mpd_host
    {
        print "Host [localhost]: ";
        chomp (my $host = <STDIN>);
        return "localhost" if !$host;
    }
    sub request_mpd_port
    {
        print "Port [6600]: ";
        chomp (my $port = <STDIN>);
        return 6600 if !$port;
    }
    sub request_mpd_password
    {
        print "Password [null]: ";
        chomp(my $password = <STDIN>);
        return "" if !$password;
    }
    return (&request_mpd_host, &request_mpd_port, &request_mpd_password);
}

sub make_sample_config
{
    my $first_config = {
        'mpd_host'     => $_[0],
        'mpd_port'     => $_[1],
        'mpd_password' => $_[2],
        patterns => [
            '#nowplaying %a - %t (%d)',
            '#nowplaying %a - %t',
        ],
        patterns_comment => [
            '#nowplaying %a - %t (%d) « %c',
            '#nowplaying %a - %t « %c',
        ],
    };
    open my $first_configfile, '>', 'config.yml'
        or die "Can't make config file: $!";
    print $first_configfile Dump($first_config);
    close $first_configfile;
}

sub check_mpd_connection_handshake
{
    my $data = <$_[0]>;
    return 1 unless $data =~ m/OK MPD/
        or return 0;
}

sub current_song_info
{ # tracktitle, artistname, albumname || 1
    my $mpd_socket = shift;
    my %response;
    print $mpd_socket "currentsong";
    while (<$mpd_socket>) {
        chomp;
        my ($key, $value) = split(': ', $_, 2);
        $response{$key} = $value;
    }
    return %response;
}

my $configfilepath = &get_config_file;
open my $configfile, '<', $configfilepath
    or print "I haven't found any configuration file, \
    maybe this is the first time you run this software.\n"
    and &first_run and exit 0;
my %config = &load_conf($configfile);
die "Malformed configuration file ($configfilepath).\n"
    if &check_conf(\%config) eq 1;
close $configfile;

my $mpd_socket = new IO::Socket::INET (
    PeerHost => $config{'mpd_host'},
    PeerPort => $config{'mpd_port'},
    Proto => 'tcp',
) or die "Error connecting to MPD socket: $!\n";
die "Error connecting to MPD daemon: maybe something else is running on $config{'mpd_port'} port"
    if check_mpd_connection_handshake($mpd_socket) eq 1;
my %tags = &current_song_info($mpd_socket);
print $tags{artist};
$mpd_socket->close();

我做错了什么？

提前致谢。