...
        my ($title, $track, $artist);
        {
          my $mp3 = MP3::Tag->new($curfile)
              or die "Didn't get an mp3 tag from '$curfile'";
          ($title, $track, $artist) = $mp3->autoinfo(); 
        };
        ...

##</code><code>##

     my $newname = File::Spec->catfile($mp3dir[$i],"$track. $artist - $title.mp3");
     my $oldname = File::Spec->catfile($mp3dir[$i],$mp3file[$i]);
    rename($oldname, $newname)
        or die "Couldn't rename '$oldname' to '$newname': $!";