#!/usr/bin/perl
use warnings;
use Cwd;
use File::Find;
my $file_pattern  ="*.txt";
find(\&d, cwd);
sub d {
  my $file = $File::Find::name;
  return unless -f $file;
  return  unless $file =~ /\Q$file_pattern\E$/;
  print "text file:$file\n";
}