For software that interfaces with Bitcoin Core via RPC, it can be useful to know whether the fRelayTxes flag is set. It could be added to `getnetworkinfo`.

if (i.second > 0)
                sendPerMsgCmd.push_back(Pair(i.first, i.second));
        }
        obj.push_back(Pair("bytessent_per_msg", sendPerMsgCmd));
        UniValue recvPerMsgCmd(UniValue::VOBJ);
        BOOST_FOREACH(const mapMsgCmdSize::value_type &i, stats.mapRecvBytesPerMsgCmd) {
            if (i.second > 0)
                recvPerMsgCmd.push_back(Pair(i.first, i.second));
        }
        obj.push_back(Pair("bytesrecv_per_msg", recvPerMsgCmd));
        ret.push_back(obj);
    }
    return ret;
}
UniValue addnode(const UniValue& params, bool fHelp)
{
    string strCommand;
    if (params.size() == 2)
        strCommand = params[1].get_str();
    if (fHelp || params.size() != 2 ||
        (strCommand != "onetry" && strCommand != "add" && strCommand != "remove"))
        throw runtime_error(
            "addnode \"node\" \"add|remove|onetry\"\n"
            "\nAttempts add or remove a node from the addnode list.\n"
            "Or try a connection to a node once.\n"
            "\nArguments:\n"
            "1. \"node\"     (string, required) The node (see getpeerinfo for nodes)\n"
            "2. \"command\"  (string, required) 'add' to add a node to the list, 'remove' to remove a node from the list, 'onetry' to try a connection to the node once\n"
            "\nExamples:\n"