On Jan 25, 2007, at 8:23 PM, Stuart MacDonald wrote: > I've read the man pages on the tools that come with Wireshark. I was > hoping to find a tool that opens a capture, applies a filter and > outputs matching packets to a new file. Here's a sample run of the > hypothetical filtercap tool: > # filtercap -r very-large.eth -w only-infrequent.eth -f > "tcp.port==50000"
tcpdump -r very-large.eth -w only-infrequent.eth tcp port 50000 That can't do arbitrary display filtering, but truly *arbitrary* display filtering has problems with reassembly (i.e., a filter that matches something in the reassembled portion of the packet can't match anything but the last packet). It also can't handle non-libpcap capture files, but given that your capture file is *from* tcpdump, it's obviously readable by tcpdump.... > tshark is almost the right thing, except that tshark also tries to > read in the whole capture first instead of processing it like editcap. No, actually, it *does* process it like editcap; neither it nor Wireshark read the entire capture file into memory. They *do* keep reassembled data in memory, but that's another matter. _______________________________________________ Wireshark-users mailing list Wireshark-users@wireshark.org http://www.wireshark.org/mailman/listinfo/wireshark-users