<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">I have a problem when joining more than one source specific multicast group. The first gen_udp:open() works as expected, I start receiving datagrams sent to the specified multicast address, and coming from the specified source. However, in another gen_server if I try to do the same, but on a different multicast and source address, I start receiving the datagrams on both the new socket as well as the first socket and from both multicast groups. The open looks like:<div class=""><br class=""></div><div class="">Port = 3100,</div><div class=""><font face="Andale Mono" class=""><span style="font-style: normal;" class="">Bin = << <<239,0,0,1>>/binary, <<0,0,0,0>>/binary, <<10,0,1,1>>/binary >>,</span></font></div><div class=""><font face="Andale Mono" class=""><span style="font-style: normal;" class="">{ok, _Socket} = gen_udp:open(Port,<br class=""> [binary,<br class=""> {active, true},<br class=""> {reuseaddr, true},<br class=""> {multicast_ttl, 30},<br class=""> {raw, 0, 39, Bin}]), %% 0 - IPPROTO_IP, 39 - IP_ADD_SOURCE_MEMBERSHIP</span></font></div><div class=""><br class=""></div><div class=""><font face="Avenir-Book" class="">I am able to join multiple multicasts, non source specific, and receive only datagrams from the correct group by using an open like:</font></div><div class=""><font face="Avenir-Book" class=""><br class=""></font></div><div class=""><div class="">Port = 3100,</div><div class=""><span style="font-family: "Andale Mono";" class="">{ok, _Socket} = gen_udp:open(Port,</span></div><div class=""><font face="Andale Mono" class=""> [binary,<br class=""> {active, true},<br class=""> {reuseaddr, true},<br class=""> {multicast_ttl, 30},<br class=""></font></div></div><div class=""><font face="Andale Mono" class=""> {add_membership, {239,0,0,1}, {0,0,0,0}}]),</font></div><div class=""><font face="Andale Mono" class=""><br class=""></font></div><div class=""><font face="Avenir-Book" class="">Any suggestions or help would be appreciated.</font></div><div class=""><font face="Avenir-Book" class=""><br class=""></font></div><div class=""><font face="Avenir-Book" class="">Mark.</font></div></body></html>