[LRUG] UTF8 errors parsing mail file

[gvim]

I'm encountering some UTF-8 errors in Ruby 2.0. When installing gems I 
often see non-fatal errors relating to conversion of ASCII characters to 
UTF-8. The following script is designed to search a large Maildir folder 
for lines beginning with 4 word characters:

---------------------------------------------------------
dir = 'my/maildir/path'
Dir.chdir(dir)

Dir.foreach(dir) do |file|
   next unless file =~ /^\d{4}/
   print "\n\n************* Opening #{file} *************\n"
   fh = File.open(file)
   while fh.gets do
     print if $_ =~ /^\w{4}\b/
   end
   fh.close
end

-------------------------------------------------------------


After successfully scanning 7 email files it dies with a UTF-8 error:


************* Opening 1270516984.M407293P18051.mac,S=1601,W=1645:2,Sb 
*************
Paul
./1.rb:13:in `block in <main>': invalid byte sequence in UTF-8 
(ArgumentError)
	from ./1.rb:8:in `foreach'
	from ./1.rb:8:in `<main>'


The equivalent Perl script parses the whole directory without any errors:

------------------------------------------------------------
use 5.016;
use autodie;

my $dir = 'my/mail/path';
chdir $dir;
opendir my $dh, $dir;

while (readdir $dh) {
   next unless /^\d{4}/;
   open my $fh, '<', $_;
   say "\n\n************* Opening $_ *************";
   while (<$fh>) {
     chomp;
     say if /^\w{4}\s/;
   }
   close $fh;
}
closedir $dh;

-------------------------------------------------------------

gvim