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`.

nMaxConnections = std::min(nFD - MIN_CORE_FILEDESCRIPTORS, nMaxConnections);
    if (nMaxConnections < nUserMaxConnections)
        InitWarning(strprintf(_("Reducing -maxconnections from %d to %d, because of system limitations."), nUserMaxConnections, nMaxConnections));
    
    fDebug = !mapMultiArgs["-debug"].empty();
    
    const vector<string>& categories = mapMultiArgs["-debug"];
    if (GetBoolArg("-nodebug", false) || find(categories.begin(), categories.end(), string("0")) != categories.end())
        fDebug = false;
    
    if (GetBoolArg("-debugnet", false))
        InitWarning(_("Unsupported argument -debugnet ignored, use -debug=net."));
    
    if (mapArgs.count("-socks"))
        return InitError(_("Unsupported argument -socks found. Setting SOCKS version isn't possible anymore, only SOCKS5 proxies are supported."));
    
    if (GetBoolArg("-tor", false))
        return InitError(_("Unsupported argument -tor found, use -onion."));
    if (GetBoolArg("-benchmark", false))
        InitWarning(_("Unsupported argument -benchmark ignored, use -debug=bench."));
    if (GetBoolArg("-whitelistalwaysrelay", false))
        InitWarning(_("Unsupported argument -whitelistalwaysrelay ignored, use -whitelistrelay and/or -whitelistforcerelay."));
    
    int ratio = std::min<int>(std::max<int>(GetArg("-checkmempool", chainparams.DefaultConsistencyChecks() ? 1 : 0), 0), 1000000);
    if (ratio != 0) {
        mempool.setSanityCheck(1.0 / ratio);
    }
    fCheckBlockIndex = GetBoolArg("-checkblockindex", chainparams.DefaultConsistencyChecks());
    fCheckpointsEnabled = GetBoolArg("-checkpoints", DEFAULT_CHECKPOINTS_ENABLED);