I should know better than to open my big yap but: pcap isn't the only way to do raw packet I/O on Linux; you can also use socket(PF_PACKET) and not need any special libraries. Maybe a bit of conditionalized code in bridge.c would make it easier to build on Linux w/o breaking it on other Unices? (Yes I'd be happy to contribute code -- I've been working on my own mopd replacement anyway partly because of how hard mopd is to build on Slackware Linux.) John Wilson D Bit