$sock_r = IO::Socket::INET->new(Proto     => "udp")
                 or die "can't connect socket to port: $!";

    $host_port = $sock_r->sockport;
    print "Listening on host_port $host_port\n";
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   print $sock_w "test 01234 $test";

00 08 74 4A 64 A0 00 02 FD B1 41 C2 08 00 45 00 ..tJd.....A...E.
00 28 A7 6B 40 00 3D 11 4F A1 BA 01 EE B0 BA 01 .(.k@.=.O.......
E4 04 80 02 14 20 00 14 98 46 74 65 73 74 20 30 ..... ...Ftest 0
31 32 33 34 20 34                               1234 4
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"Ftest 01234 4" is an ascii string as your testing shows. If you want to try some non-ascii data in the quoted string try sending "\01\02\03" that will send non-ascii data (OK, these are in the ascii set, but are "control characters"). You can use pack to put "binary" data into a scalar.

HTH, --john

For the first question, you have to specify LocalAddr, that should resolve your problem. For example:

use IO::Socket::INET;

$sock_r = IO::Socket::INET->new(Proto => "udp", LocalAddr => "127.1")
                 or die "can't connect socket to port: $!";

    $host_port = $sock_r->sockport;
    print "Listening on host_port $host_port\n";
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For you second part, just as jasonk said UDP does not understand what ASCII is, or what binary is, it is just a stream of bytes. Encoding is controlled by your script. Absolutely nothing to with UDP, and UDP absolutely does not care that.

As for syntax, you write binary data to socket in the same way you swrite ascii data to it. The socket does not know, and does not care what you are sending.

Thank you All so much!!

Adding "LocalAddr" was all I needed and now $sock_r->sockport returns the listening port.

Sending $hex hi thru my write socket is exactly what I need!

    
# results in "4567" in datagram trace - WINNER!!
my $hex_hi  = pack("H*", "4567");
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