Perl script for generating iTunes xml Metadata for MP3 CDs/DVDs

Many years ago, I wrote a script in Perl that was meant to create a cached metadata of MP3 files (in Apple's plist/XML format) which iTunes uses when you insert a CD/DVD full of MP3 files (the same would be true for AAC files, but I limited the scope of my project, due to lack of usable libraries back then).

Since my Perl is rusty, I would love to have some feedback and constructive criticism on how to make the script better, especially regarding readability.

Since the script is trivial, but long, I don't know how much I should put it here. The whole script is in one of my github repositories, if you want to see it.

An abridged version of it is:

```
#!/usr/bin/perl -W
# Copyright (C) 2009 Rogério Brito
# This program is Free Software and is distributed under the terms of
# the GNU General Public License version 2 or, at your option, any
# latter version.

use strict 'vars';
use warnings;
use utf8;

use Encode qw(encode decode);
use MP3::Tag;

# ==============================================================================
# Auxiliary functions for generation of the output
sub pr_header {
print FH

Current Version1
Compatible Version1
Applicationm3s v0.0
Burner Info$_[0]
Disc ID$_[1]
Disc Name$_[2]
tracks

EOF
}
sub pr_footer { print FH "\t\n\n\n"; }

# ==============================================================================
# Functions to generate the proper XML tags for iTunes.
sub pr_open_dict { print FH "\t\t\n"; }
sub pr_key { print FH "\t\t\t", my_utf8_encode($_[0]), ""; }
sub pr_string { print FH "", my_utf8_encode($_[0]), "\n"; }
sub pr_integer { print FH "", my_utf8_encode($_[0]), "\n"; }
sub pr_date { print FH "", my_utf8_encode($_[0]), "\n"; }
sub pr_boolean { print FH ($_[0])?"\n":"\n"; }
sub pr_close_dict { print FH "\t\t\n"; }

# ==============================================================================
# Auxiliary functions
sub gen_serial_no {
return sprintf("%04X%04X%04X%04X",

Agree with what Vedran wrote. I'd also add some prototypes to go with that, so that perl can give you warnings or errors when you miss a parameter; e.g., something like

sub foo($) {

}

to specify that this sub takes two scalars as parameters.

There are some limitations to what you can do with perl's prototypes like this, but it's still useful.

StackExchange Code Review Q#29602, answer score: 2