#!/usr/bin/perl
use strict; my %count; my $directory = "\\Test";
opendir( DIR, $directory )
  || die "Unable to open directory - $!\n";
my @files = grep /\.txt/, readdir( DIR );
closedir( DIR );

open( OUTFILE, ">> $directory\\COID_LIST.txt" )
  || die "Unable to open write file! - $!\n";

foreach my $file (@files) {
    open( FH, "$directory\\$file" )
      || die "Unable to open $file - $!\n";
    while( <FH> ) {
        my $ID = substr( $_, 260, 5 );
        print OUTFILE "$ID\n";
        $count{$ID}++ if ( defined( $ID ) );
    }
    close( FH );
}

print "Number of company ID = " . scalar keys %count;

sub process_files
{
    if ($File::Find::dir ne $dir)
    {
        $File::Find::prune = 1;
        return 0;
    }

    return 0 if ($_ !~ /\.txt$/);

    copy($File::Find::name, "\\temp\\$_") or die "Failed to copy $_: $!\n";
    return 1;
}

find(\&process_files, $dir);


Sub renaming_files
{

   foreach my $file (glob "*.old") {
     my $newfile = $file;
     $newfile =~ s/\.old$/.new/;
     
     if (-e $newfile) {
        warn "can't rename $file to $newfile: $newfile exists\n";
     } elsif (rename $file, $newfile) {
       ## success, do nothing
     } else {
        warn " rename $file to $newfile failed: $!\n";
     }
}