It was thus said that the Great Sean Conner once stated:
It was thus said that the Great Clark Snowdall once stated:
Everyone,
Thanks for the suggestions ... some of them were helpful.
I've done some more exploration, and I think the issue is I can't
send
a UDP broadcast packet. I can see non-broadcast packets, but when I
select the ip address for broadcast, it doesn't show up. Could it
be
something with my router? Or lua UDP doesn't really like broadcast?
Any suggestions?
If you want to send a broadcast packet, you need to set an option
on the
socket to do so. In C (under Unix) this would be:
rc = setsockopt(sock,SOL_SOCKET,SO_BROADCAST,&dummy,sizeof
(dummy));
if (rc < 0)
{
perror("setsockopt(SO_BROADCAST)");
return(EXIT_FAILURE);
}
You'll need to find the equivilent under the Lua library you are
using.
I checked back and I see you are setting the broadcast flag. I
checked an
old project of mine (testing broadcast UDP packets) and I see that
in the
server side I have:
local = "10.0.0.3:2020"; /* well, these are actually struct
sockaddr */
remote = "10.0.0.255:2020"; /* but you get the idea ... */
sock = socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);
setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,&dummy,sizeof(dummy));
setsockopt(sock,SOL_SOCKET,SO_BROADCAST,&dummy,sizeof(dummy));
bind(sock,&local,sizeof(local));
while(1)
{
sendto(sock,data,sizeof(data),0,&remote,sizeof(remote));
}
And oddly enough, in the client side:
local = "10.0.0.2:2020";
sock = socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);
setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,&dummy,sizeof(dummy));
setsockopt(sock,SOL_SOCKET,SO_BROADCAST,&dummy,sizeof(dummy));
bind(sock,&local,sizeof(local));
while(1)
{
recvfrom(sock,&data,sizeof(data),0,&remote,&dum);
}
It looks like you need to set the recieving socket with the broadcast
option as well.
-spc
