Difference between -R and -Y.

As far as I can tell this also depends on the version of tshark you're using, in newer versions use -Y, older versions -R. For the exact meaning of those options see the tshark manpage. I'm guessing you haven't read that page yet, since then you would know the answer to your next questions is that -Y is the display filter, so you can use that to apply the filters on tcp.options.mss_val, tcp.flags, and icmp.type that you are asking about.

In a captured frame, there are protocols like "eth(0):ip(0):gre:eth(1):ip(1):tcp"

I'm not quite sure what you mean - could you show some of the actual tshark output you're having a problem with? If I'm understanding your sample output, $src_addr contains the string "1.1.1.1,2.2.2.2"??

In reply to Re^5: filter tcpdump packets by Anonymous Monk
in thread filter tcpdump packets by syboar

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