sort files as per their dated names at the same time create filehandles for each file in perl - perl

Question

I have the about 1000 files named as
CU20130404160033.TXT
CU20130405160027.TXT ....
CUYYYYMMDDHHMMSS.TXT
I need to append all the files into single file as per names where where min(date) to max(date)
How can i make the programm efficient where i should sort the files as per their Dates and create filehandles.
opendir (DIR, $Directory) or die $!;
#files = grep { (!/^\./) && -f "$Directory/$_" } readdir(DIR);
chdir($Directory);
#create an array of open filehandles.
#fh = map { open my $f, $_ or die "Cant open $_:$!"; $f } #files;
#create new file for output
open $out_file , ">$filename" or die "cant open new file $!";

Answer 1

Something like this should be helpful.
opendir (DIR, $dir);
#dir=readdir(DIR);
closedir(DIR);
#Sort file list by modification time and write to an output file
open(my $fh, ">", "output.txt") or die $!;
print $fh sort{ -M "$dir/$b" <=> -M "$dir/$a" }(#dir);
close $fh;

Answer 2

I propose this script:
use strict;
use warnings;
#1. Set up the general values
my $directory = "... the dir ...";
my $out_file = "... the out file ...";
#2. Fill an array with the names of your files
opendir(my $dh, $directory) or die $!;
while( my $file = readdir($dh) ) {
push #files, $file;
}
closedir $dh;
#3. Sort the array
#files = sort {$a cmp $b} #files;
#4. Open the target file
open $out_file , '>', $filename or die $!;
#5. Iterate for each input file, open it,
# and write line by line its contents to the target
foreach my $filename(#files) {
open my $ifh, '<', $filename or die $!;
while( my $line = <$ifh> ) {
print $out_file $line;
}
close $ifh;
}
#6. Close the target
close $out_file;