if ( -1 != index $log, '198.167.1.10' ) { push @ip, $log; # or... print $log # or whatever makes sense for you } # OR just written differently push @ip, $log if -1 != index $log, '198.167.1.10'; print $log if -1 != index $log, '198.167.1.10'; # Or... as a regexp but I prefer it the other way push @ip, $log if $log =~ /198\.167\.1\.10/; print $log if $log =~ /198\.167\.1\.10/;