Something like this perhaps?

...
use List::Util qw{ max };
...
my %filesByAge = map { ( stat $_ )[ 9 ], $_ } glob q{*.rtf};
my $mostRecent = $filesByAge{ max keys %filesByAge };
...
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It might not pick the particular file you want if you have a lot of RTFs created at exactly the same time but that sounds unlikely.

I hope this is helpful.

That did work, using
open INPUT, "<$mostrecent"; after the code that you supplied!

The file test operators -X -M will give you the modification time, so something like

my $last = ( sort {-M $a <=> -M $b} glob('*.rtf') )[0];
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Do check the docs for glob, as it doesn't take a regex but a shell-like file match expression.

#!/usr/bin/perl
#check File::Find and note that the mtime
#of a directory matches that of its newest file (for static files).

#You can use the module File::Find to traverse the directory 
#structure and use stat to find the age of the file. The 
#example below sets up a hash data structure that contains 
#the name of the file and the last accessed modified time. 
#The application then compares the values in the hash and 
#prints out the newest file.

use strict;
use File::Find;
use vars qw/%files/;

sub findNewestFiles {
my $element = $File::Find::name;
return if (!-f $element);

$files{$element} = (stat($element))[9];

}

#######################################################
# MAIN
#######################################################
my $dir = '/home/zentara/1down';
find(\&findNewestFiles, $dir);
my $newestfile;
my $time = 0;
while(my ($k, $v) = each(%files)) {
if ($v > $time) {
$newestfile = $k;
$time = $v;
}
}
$time = localtime($time);
print "The newest file is $newestfile : $time\n";
exit;
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A second more complex version

#!/usr/bin/perl
#check File::Find and note that the mtime
#of a directory matches that of its newest file (for static files).
#that is NEWEST not where the last file was modified(edited)

#find the directory with the most recent modified time,
#then use glob on that directory to find the most recent file.
#That might be more efficient given the number of files and
#directories that you are searching through because you would
#only be storing directories in the hash and the application would
#not be calling stat on all those files.

#You can use the module File::Find to traverse the directory
#structure and use stat to find the age of the file. The
#example below sets up a hash data structure that contains
#the name of the file and the last accessed modified time.
#The application then compares the values in the hash and
#prints out the newest file.

use strict;
use File::Find;

my %dirs;

my $dir = '/home/zentara/1down';
#######################################
find(\&findNewestdirs, $dir);
sub findNewestdirs {
my $element = $File::Find::name;
return if (!-d $element);
$dirs{(stat($element))[9]} = $element;
}
######################################
my @times1 = sort { $a <=> $b } keys %dirs;
my $tmax = pop @times1;
my $newestdir = $dirs{$tmax};

#now find latest file in the latest dir
my $lat_file;
while (glob ("$newestdir/*")) {
#for Access time, not creation time
#$lat_file = $_ if ((-f) && (!defined ($lat_file) || -A $_ < -A $lat_f
+ile));

$lat_file = $_ if ((-f) && (!defined ($lat_file) || -M $_ < -M $lat_fi
+le));
}
if (defined ($lat_file)) {
print "latest_file is $lat_file\n";
}
exit;
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It might also be useful to consider tools like File::Find::Rule and its brethren, to provide a more platform-independent and/or perhaps easier to modify approach to the task.   Sometimes you find code that contains “a set of chicken-scratches that works,” and your task is to modify it.   :-O!!   It therefore might be worth considering an approach that, from the outset, delegates the file-searching and/or selection process to an existing body of CPAN code with an eye toward long-term serviceability and maintainability.