my $rh_set = IO::Select->select($read_set, undef, undef, 0);
foreach my $rh (@$rh_set) {

##</code><code>##

my($rh_set) = IO::Select->select($read_set, undef, undef, 0);
foreach my $rh (@$rh_set) {

##</code><code>##

my @rh_set = $read_set->can_read();
foreach my $rh (@rh_set) {