Update: Please note that this solution searches for the files recursively. Thanks to aristotle for the clarification

Use File::Find

Untested

#!/usr/bin/perl -w

use File::Find;
use strict;

my $dir = '/path/to/dir/';

my $oldestfile = 0;
my $filename = "No BOT REPORT: ERROR";

finddepth(\&oldfile, $dir);
print "oldest file = " , $filename,$/;

sub oldfile {
    return unless (/BOT/);
    my $mtime = -M $_;
    if ($mtime > $oldestfile) {
        $filename = $File::Find::name;
        $oldestfile = $mtime;
    }
}

[download]

BTW i think you are not getting the files using the readdir due to the context

from perldoc -f readdir 

 readdir DIRHANDLE
Returns the next directory entry for a directory opened by "opendir". 
+If used in list context, returns all the rest of the entries in the d
+irectory.  If there are no more entries, returns an undefined value i
+n scalar context or a null list in list context.

[download]

In reply to Re: Finding Oldest File in a Directory by sk
in thread Finding Oldest File in a Directory by awohld

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