#!/usr/bin/perl
open FH, "master.cfg" or die $!;
open FH1, "config1.cfg" or die $!;
while(my $line=<FH>){
chomp;
my %hash;
(my $key,my $value) = split /=/, $line;
$hash{$key} = $value;
while(my $line2=<FH1>){
chomp;
my %hash1;
(my $key1,my $value1) = split /=/, $line;
$hash1{$key} = $value;
open FH1, ">config1_new.cfg" or die $!;
if ($value1 != $value)

##</code><code>##

[root@localhost test]# cat master.cfg
env=qa
env_var2=val2
env_var1=val1
env_var3=val3
env_var4=val4
env_var5=val5
[root@localhost test]# cat config1.cfg
env_var3=x
env_var4=y
Var=conf

##</code><code>##

variavle=value
env_var2=val2
env_var1=val1