# untested code...
my $config_dir = "/path/to/script/config";
my $config_file = $config_dir . "/" . "config.file";
my %config = read_config($config_file);

sub read_config {
  my $config = shift || die "Config file name not supplied \n";
  open(CONFIG, $config) || die "Could not read from $config: $!\n";
  # code to parse config file goes here
  close(CONFIG);
  return %config;  # or @config or .... 
}