#!/usr/bin/perl
use strict;
use File::Copy;
use warnings;
my $open_file= "C:/oracle/ora81/network/ADMIN/SQLNET.ORA";
my $write_file=">>C:/oracle/ora81/network/ADMIN/SQLNET.ORA";
open(IN,$open_file) || die "cannot open $open_file $!";
open(OUT,$write_file) || die "cannot create $write_file $!";
while (<IN>) {
  if ($_ = /^SQLNET\.AUTHENTICATION_SERVICES=\ \(NTS\)$/){
    print  "\#\ ^SQLNET\.AUTHENTICATION_SERVICES=\ (NTS)";
    print OUT $_  "\#\ SQLNET\.AUTHENTICATION_SERVICES=\ (NTS)";
#Want to write the 2nd string print ... to OUT write handle  
#OUT $_
  }
}

##</code><code>##

String found where operator expected at ora.pl line 22, near "$_  "\#\ SQLNET\.AUTHENTICATION_SERVICES=\ (NTS)""
	(Missing operator before "\#\ SQLNET\.AUTHENTICATION_SERVICES=\ (NTS)"?)
syntax error at ora.pl line 22, near "$_  "\#\ SQLNET\.AUTHENTICATION_SERVICES=\ (NTS)""
Execution of ora.pl aborted due to compilation errors.