If your intention is to simply determine if or not TCP opens on a port (i.e. you don't care about the protocol being transmitted on TCP), this can be done simply with TCP Ping (which just establishes TCP and then closes the connection).

Example:

use AnyEvent::Ping::TCP;
my $t = tcp_ping '10.0.0.2', 1235;
my $result = defined $t ? "OK" : "Failed";
print $result."\n";
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