Thanks guys. Especially McA and Corion. I have this figured. This is what I have done so far and it seems to work. Please suggest any improvements or blunders that I am making with the code. 
use strict;
use warnings;

use constant {
    FILE_A  => './kma',
    FILE_B  => './kma2',
};

my %a_hash;

my @a_array;
my @b_array;

open my $a_fh, "<", FILE_A;
while (<$a_fh>) {
chomp;
my ($key, $value) = split '=', $_, 2;
$a_hash{$key} = $value;
}

open my $b_fh, "<", FILE_B;
while (<$b_fh>) {
chomp;
my ($key, $value) = split '=', $_, 2;
$a_hash{$key} = $value;
}

open my $c_fh, ">", FILE_A or die $!;
print $c_fh "$_=$a_hash{$_}\n" for (keys %a_hash);

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In reply to Re^2: Merge the difference between two files and save it on the first file. Also update the first file with info in second file. by Shariq
in thread Merge the difference between two files and save it on the first file. Also update the first file with info in second file. by Shariq

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