There are some potential feefilter cleanups mentioned and motivated in comment https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-805808485 . If you address the locking one, please be careful and make sure that `round()` is only called under a lock. See https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-807992199

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}
#ifndef WIN32
    if (!args.GetBoolArg("-sysperms", false)) {
        umask(077);
    }
    
    registerSignalHandler(SIGTERM, HandleSIGTERM);
    registerSignalHandler(SIGINT, HandleSIGTERM);
    
    registerSignalHandler(SIGHUP, HandleSIGHUP);
    
    signal(SIGPIPE, SIG_IGN);
#else
    SetConsoleCtrlHandler(consoleCtrlHandler, true);
#endif
    std::set_new_handler(new_handler_terminate);
    return true;
}
bool AppInitParameterInteraction(const ArgsManager& args)
{
    const CChainParams& chainparams = Params();
    
    
    
    
    
    std::string network = args.GetChainName();
    if (network == CBaseChainParams::SIGNET) {
        LogPrintf("Signet derived magic (message start): %s\n", HexStr(chainparams.MessageStart()));
    }