You pushed in result array a array ref:

$filesanddates[$filecounter] = \@fileanddate;
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and you should use following:

$logfilename = $filesanddates->[$listcount][0];
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instead of

$filesanddates[$filecounter] = \@fileanddate;
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But I would like to offer you another way:

       !/usr/bin/perl -w
       
       use strict;
       
       # You can use this module for dumping your data.
       use Data::Dumper; 
       
       # Function which forms an files array 
       sub one {
          my $dir = shift; # Dir name

          opendir(DIR, $dir) or die "Can't open $dir: $!";
          my @files = grep { !(/^\./) && /^post/ && -f } readdir(DIR);
          closedir(DIR);
                
          my $res; # Array reference which will consist results
      
          @$res = map { [$_, (stat($_))[9]] } @files;              
          
          return $res;
      }

      # Function which processes result array 
      sub two {
          my $array = shift;
      
          for(@$array) {
              print $_->[0] .': '.$_->[1]."\n";
              
              <do something> ...
          }
      }
      
      # Call our functions 
      two(one('/var/logs'));
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========================
{ firstname => 'Michael',
quote => 'Mice were crying and stinging but went on nibbling the cactus', }