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use 5.16.2;

my @finalnwlist = ( '192.169.32.0/255.255.255.0',
                    '192.169.72.0/255.255.255.0',
                    '192.169.73.0/255.255.255.0');

my @output = replace_exports();
use Data::Dumper; say Dumper \@output;

sub replace_exports {
  chomp(my @lines = <DATA>);

  my @changes;
  foreach my $line (@lines) {
    if ($line !~ /\*/) {
      push(@changes,$line)
    } else {
      foreach my $server (@finalnwlist) {
        my $output = $line;
        $output    =~  s/\*/$server/g;
        push(@changes,$output);
      }
    }
  }

  return @changes;
}

__DATA__
/file1 *(rw,sync,no_root_squash,no_subtree_check)
/file2 *(ro,sync,no_root_squash,no_subtree_check)
# shares for Tsp InstallServer
file3 *(ro,sync,no_subtree_check)
[download]