c:> rename.pl .*\.mp3 1(\d\d.*) 4$1


##</code><code>##

my $inputMask = $ARGV[0];
my $regexSearch = $ARGV[1];
my $regexReplace= $ARGV[2];

my @files = <*.*>;

foreach my $file ( @files )
{
	if ( $file =~ /$inputMask/ )
	{
		my $oldname = $file;
		$file =~ s/$regexSearch/$regexReplace/;

		rename($oldname, $file) or die "$oldname to $file failed: $!";
		print "renamed $oldname to $file\n";
	}
}