my $folder =  '/Users/chaz/Documents/perl/MailingList/Last.Mailing.Archive_20150218-1450/messages'; 
<\code>

<P>
This then causes the debugger, i.e. perl -d &ltfilename&gt to emit this error:
</P>

<code>
Use of uninitialized value $tid in concatenation (.) or string at /System/Library/Perl/5.18/perl5db.pl line 1831.
 at /System/Library/Perl/5.18/perl5db.pl line 1831.
	DB::_DB__read_next_cmd(undef) called at /System/Library/Perl/5.18/perl5db.pl line 2741
	DB::DB called at create_dead_eamil_list.pl line 45