if bpf fd's select()able?

Dmitry Morozovsky marck at rinet.ru
Sun Sep 7 12:46:58 PDT 2003


Dear colleagues,

[all below is for 4-STABLE]

I'm trying to write effective arp scanner for multi-interface router (esp.
multi-vlan); I plan to use multiple bpf devices attached to different
interfaces emitting ARP requests and filters listening to ARP replies; the most
natural way to multiplex them for me is select().

However, my tests show that select()ing bpf fd does not lead to trigger packets
available to bpf filter; the process hangs in select state while parallel
tcpdump process shows packets desired *and* is in bpf state.

Am I missing something "base"? References (surely, I'd already read
manpages for bpf, pcap and related -- but did I still missed something
serious?) would be greatly appreciated.

Thanks for your time, as always.

Sincerely,
D.Marck                                     [DM5020, MCK-RIPE, DM3-RIPN]
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*** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck at rinet.ru ***
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