Check if UDP port is opened in Perl -


i need check if remote udp port opened. part of code is:

sub scanudp {     $address = shift;     $port = shift;     $udpsocket = new io::socket::inet (                                         peeraddr => $address,                                         peerport => $port,                                         proto => 'udp',                                         ) or return 0;     $udpsocket -> send ('hello', 0);     #........some code.............     return 1; }

..some code.. should check if received icmp packets "host unreached" or "port unreached" check if port opened. how can it?

generally can't. udp not have connected state, in no way required send reply packet sent. , that's when ignoring package loss. may positive reply if sent valid request in whatever protocol you're accessing , remote port open, absence of such reply can not used make conclusions.


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