$ cat spw638403.txt
aajkaj  XYZtcpHJHKtcpKJHKH
ashhgdasjh    JKHKJHtcpUUHtcpHDKJHtcpJHDJAHD
kjkjn  NHYtcpHHGJJH
$ cat spw638403.addr
Address1=
Address2=
Address3=
$

##</code><code>##

#!/usr/bin/perl -i.bak
#
use strict;
use warnings;

my @list = ();

BEGIN
{
    my $inFile = q{spw638403.txt};
    open my $inFH, q{<}, $inFile
       or die qq{open: $inFile: $!\n};

    while ( <$inFH> )
    {
        chomp;
        push @list, ( split m{tcp}, ( split )[1] )[0];
    }

    close $inFH
       or die qq{close: $inFile: $!\n};
}

while ( <> )
{
    s{$}{$list[$. - 1]};
    print;
}

##</code><code>##

$ ./spw638403 spw638403.addr
$ cat spw638403.addr
Address1=XYZ
Address2=JKHKJH
Address3=NHY
$