#!/usr/bin/perl

use strict; # https://perlmonks.org/?node_id=11151755
use warnings;

my @paths = @ARGV;
my %seen;
while( my $path = shift @paths )
  {
  $path eq '/data/logs/master' and next;
  unshift @paths, grep -d, <$path/*>;
  -f and $seen{join ' ', (stat)[0,1]}++ == 0 and save_file($_)
    for <$path/*auth.log>;
  }