Tshark is another application that identical to Tcpdump

No, it's much more powerful - have a look again at the tshark manpage, especially the -T fields and -e options. You can use them to output Wireshark's tcp.options.mss_val field.

As for your output, it looks like the packets don't contain an MSS option, or, if you know the packets do have one, NetPacket::TCP isn't parsing them correctly, in that case file a bug with the module.

In reply to Re^3: filter tcpdump packets by Anonymous Monk
in thread filter tcpdump packets by syboar

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