> -----Original Message----- > From: linux-net-owner@xxxxxxxxxxxxxxx > [mailto:linux-net-owner@xxxxxxxxxxxxxxx] On Behalf Of grimson > Sent: Wednesday, April 15, 2009 7:02 AM > To: linux-net@xxxxxxxxxxxxxxx > Subject: Re: Get name and ip-address for each interface > > So far I learned that the information Im looking for, is the interface > index. > If I receive a message on one of my interfaces I can receive > it with UDP > (oh yes I forgot to tell you that I have to use UDP) function recvfrom > or better "recvmsg". > > With recvmesg I do not only receive a message from any > client, but also > get back a filled "struct cmsghdr" (which I have to > initialize first, of > course). > > I got this information from Steven's Unix Network Programming. Amongst > the data I get back from a filled "struct cmsghdr" is also > the interface > index of my interface. Exactly what Im searching for. > _BUT_ Unfortunally I get this information only if the symbol > "HAVE_MSGHDR_MSG_CONTROL" is defined. And this is not the case on my > system. Please correct me, if I did not unterstand this matter! > So what can I do to get that symbol defined? For owner of this book, > its on page 588-592. > > It would be great if anybody could help me at this point. > > Sincerely Chris > > grimson schrieb: > > Hello out there, > > I got an interesting but challenging problem. > > I want to create a daemon-process, which runs on a host with several > > NICs. If the daemon gets a request from one of the interfaces, it > > should, amongst others, send back the IP-address and/or MAC-address, > > interface-name... of the interface from which the request > came. And only > > of that interface. No infos about local-interfaces and so on. > > > > My approach so far was to invoke ioctl with the > SIOCGIFCONF-request and > > collect all informations about every active interface on > the host. But I > > need at least one unique identifier of the interface from which the > > request came. With the interface-name for exeample I can call the/ > > /SIOCGIFADDR-request to get the IP-address. How can I achive this. > > > > Has anybody an idea. > > > > Thanks in advance. > > One alterative to the approach you are taking which might get you what you want might be to create several sockets, one bound to each network interface/IP address you want to do this on. Then when you receive a packet on one of these sockets, you know which interface it came in on from the socket descriptor and can respond appropriately. Just a thought, Jeff Haran -- 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
