I want to query (and set) the multicast TTL and loopback values using getsockopt (setsockopt). no errors occur, but no values are returned either. i can't use CPAN IO::Socket::Multicast due to configuration management restrictions. 

use Socket;
require "netinet/in.ph";
my $s;
socket($s, PF_INET, SOCK_DGRAM, getprotobyname('udp')) or  die;
my $ttl = getsockopt($s, getprotobyname('ip'), IP_MULTICAST_TTL()) or 
+die;
print "ttl => $ttl\n";

[download]

results are "ttl =>". same thing happens with IP_MULTICAST_LOOP. and as expected, since i can't query the value, setsockopt also fails.

i am running perl version 5.8.4 on solaris 10. this is the standard package delivered with solaris 10 installation disks and has not been altered.

i ran "perl -V" and the results included "usesocks=undef" but the libraries included "-libs=-lsocket" and "perllibs=-lsocket". perhaps this is related?

thank you for any advice you can give me

In reply to Values of Multicast Socket Options on Solaris 10 are not returned by getsockopt. by Anonymous Monk

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