From: Detlef Vollmann <dv@xxxxxxxxxxx> Date: Tue, 06 Mar 2007 07:52:56 +0100 > Bernd Eckenfels wrote: > > > > In article <45EC8D42.57D11665@xxxxxxxxxxx> you wrote: > > > True, which in my case is 255.255.255.255 (local broadcast). > > > (which is internally 0.0.0.0), but not if bound to 192.168.100.100 > > > > 255.255.255.255 != 192.168.100.100 - thats why you dont receive traffic for > > 255.255.255.255 if you bind to 192.168.100.100 > True, but isn't that the whole idea of broadcasts, that you get > them even if your IP address doesn't match? > > I've read the RFCs, and I got the feeling that you should get > them, but then the RFCs don't talk about sockets and bind... > > I'm told that other operating systems work as I expect, but I > still have to test this. Let's stop this idiotic thread already. SO_BROADCAST, forever and since the beginning of time, allows your socket to BIND to and SEND to broadcast addresses, otherwise attempts to bind or send to broadcast addresses will error with -EACCESS. That is the sole meaning of SO_BROADCAST, there is nothing more to it. Please go read R. Stevens for more info, this list isn't "BSD sockets 101" :-) Start with page 437 of TCP/IP Illustrated Volume 2, figure 15.4 "so_option" values, it explicitly states that SO_BROADCAST means "socket can send broadcast messages" _NOT_ anything about the socket receiving broadcast messages. I can see where you perhaps get this idea from, the Linux section 7 man page for "socket" has language that suggests that SO_BROADCAST influences packet reception, but this is totally wrong. It wouldn't be the first time the Linux man pages have an inaccuracy :) - To unsubscribe from this list: send the line "unsubscribe linux-net" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
