#!/usr/bin/perl
die "File $ARGV[0] doesn't exist" unless -f $ARGV[0];
use MP3::Mplib;
my $mp3 = MP3::Mplib->new($ARGV[0]);
my $v2tag = $mp3->get_v2tag;
print "Error writing tags of $ARGV[0]\n" unless $mp3->set_v2tag($v2tag,&UTF8);

cd mp3directory                                    # Go to the directory with the mp3(s)
ls *mp3 | xargs ~/the-script                  # Apply the script to each of them

find /mp3 -name "*.mp3"  -print | xargs mp3-utf8.pl

#!/usr/bin/perl

use strict;
use MP3::Mplib;

my $directory=shift or die "Give a directory to process recursively\n"; #Argument directory is read into variable $directory

if(! -d $directory)
{
  die "Directory $directory doesn't exist\n";
}

# the directory exists, now we are reading its contents and do our job.

#### Functions ####

###############################################################################
#
# processDirectory
#
# To process a directory recursively. It calls itself with new arguments
# (directories) when it finds one.
#
# input parameters: 1: a directory to process.
# output: none
#
###############################################################################
sub processDirectory
{
  my $dirToProcess=shift;
  opendir DH,"$dirToProcess";
  my @files=readdir DH; # Read directory contents into array
  closedir DH;
  foreach my $item (@files) # Loop through array with files
  {
    next if $item =~ /^\.\.?$/; # Skip directories '.' ond '..' for obvious reasons
    if(-d "$dirToProcess/$item") # Is this item a directory?
    {
      processDirectory("$dirToProcess/$item");
      next;
    }
    if(-f "$dirToProcess/$item" && $item =~ /\.(mp3|MP3)$/) # Is this item a File AND does it end on mp3 or MP3 ?
    {
      rewriteFile("$dirToProcess/$item");
      next;
    }
    # This is obviously no mp3 file or directory
    warn "Skipped:   $dirToProcess/$item: no mp3 file\n";
  }
}

###############################################################################
#
# rewriteFile
#
# To do the actual rewriting (this was the original script in fact.
# I do not have these libraries, so I couldn't test the error handling
#
# input parameters: 1: a file (mp3) to rewrite the tags of
# output: none
#
###############################################################################
sub rewriteFile
{
  my $fileToRewrite=shift;
  my $mp3 = MP3::Mplib->new($fileToRewrite);
  my $v2tag = $mp3->get_v2tag;
  $mp3->set_v2tag($v2tag,&UTF8) or warn("Error writing to file $fileToRewrite: $!\n");
  print "Processed: $fileToRewrite\n";
}

#### Main program (very small :) ) ####

processDirectory($directory);