As part of your complete solution, perhaps the module File::DirList would be helpful, as you can get the newest file in a directory from it:

use strict;
use warnings;
use File::DirList;

my $dir = '.';
my $newestFile = File::DirList::list( $dir, 'M' )->[0]->[13];
print $newestFile;
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Hope this helps!

Another part would be File::Tail.

#!/usr/bin/perl

use strict;
use warnings;
use Logfile::Tail ();
use Data::Dumper::Concise;

my $file = new Logfile::Tail('/var/log/messages',
     {autocommit => 1 },
);

my $line = $file->getline();
$file->commit();
print Dumper( $line );
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You obtain all the names fitting in a date in the dir, you sort the files, you pick the first and break the loop. This is more or less the idea

I had the same problem in one of my small projects, solved using a system line like:

Always opening the most recent file as long as the timestamp in its filename is right

(Entire script, just in case you want to read it, here)

So you need to monitor a directory for file creation events, right? Googling similar quiestion reveals some links which describe the way of solving the problem: File::ChangeNotify, described as cross-platform, File::Monitor, also passing tests on all operating systems, Win32::ChangeNotify, SGI::FAM, using the FAM daemon for *nix-like systems, Linux::Inotify2 and Linux::Inotify.

I had to do this once, with the added fun of arbitrarily complex processing of the log lines. I used POE::Wheel::FollowTail http://search.cpan.org/dist/POE/lib/POE/Wheel/FollowTail.pm which worked a treat. Probably overkill, but it opens a whole world of event based log processing fun to you. I handled some busy weblogs and as well as looking for errors, produced a pile of stats every minute too

Cheers,
R.