open FILE,"tnsnames.ora" or die $!;
{local $/=undef; $_ = <FILE>; }
close FILE;

##</code><code>##

open(FILE, '<', 'tnsnames.ora')
  or die "Cannot open tnsnames.ora for reading, stopped ",$!;
my $tnsnames = '';
for (<FILE>) {
  next if /^#/;
  $tnsnames .= $_;
}
close FILE;