#!/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; }