#!/usr/bin/perl -w
use strict;
use File::Find;

my @dirs = ('C:/temp');
my %options = (preprocess =>\&newest, wanted=>\&wanted, 
               bydepth=>1); # bydepth didn't work on Windows XP!!
find (\%options, @dirs);

sub newest
{
   # print "processing $File::Find::dir for ".@_." entries\n";
   # takes a list and returns a list of directories/files for
   # further processing..
   my $newest_file;
   my @files;
   
   foreach (@_)
   {
      if (!-f) {push @files, $_} # links,directories
      elsif (/\.txt$/)
      {
         $newest_file ||= $_ and next;
         $newest_file = $_ if (-M > -M $newest_file);
      }   
   }
   unshift (@files, $newest_file) if ($newest_file);
   
   return(@files);
}

sub wanted
{
   return if -d;
   print "$File::Find::name\n"; #only one "newest .txt file!"
}
__END__
Newest .txt file in each directory...
C:/temp/10.txt
C:/temp/inline/_Inline/build/_24to32/Comments.txt
C:/temp/Martin-GermanSchoolProject/output.txt
C:/temp/students/debug_notes.txt