diff --git a/src/bench/bench_bitcoin.cpp b/src/bench/bench_bitcoin.cpp
index 4b39db166..0f8f3d8c0 100644
--- a/src/bench/bench_bitcoin.cpp
+++ b/src/bench/bench_bitcoin.cpp
@@ -1,107 +1,116 @@
 // Copyright (c) 2015-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <bench/bench.h>
 
 #include <crypto/sha256.h>
 #include <key.h>
 #include <random.h>
 #include <util.h>
 #include <validation.h>
 
 #include <boost/lexical_cast.hpp>
 
 #include <memory>
 
 static const int64_t DEFAULT_BENCH_EVALUATIONS = 5;
 static const char *DEFAULT_BENCH_FILTER = ".*";
 static const char *DEFAULT_BENCH_SCALING = "1.0";
 static const char *DEFAULT_BENCH_PRINTER = "console";
 static const char *DEFAULT_PLOT_PLOTLYURL =
     "https://cdn.plot.ly/plotly-latest.min.js";
 static const int64_t DEFAULT_PLOT_WIDTH = 1024;
 static const int64_t DEFAULT_PLOT_HEIGHT = 768;
 
 static void SetupBenchArgs() {
     gArgs.AddArg("-?", _("Print this help message and exit"), false,
                  OptionsCategory::OPTIONS);
     gArgs.AddArg("-list",
                  _("List benchmarks without executing them. Can be combined "
                    "with -scaling and -filter"),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-evals=<n>",
         strprintf(
             _("Number of measurement evaluations to perform. (default: %u)"),
             DEFAULT_BENCH_EVALUATIONS),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-filter=<regex>",
                  strprintf(_("Regular expression filter to select benchmark by "
                              "name (default: %s)"),
                            DEFAULT_BENCH_FILTER),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-scaling=<n>",
         strprintf(_("Scaling factor for benchmark's runtime (default: %u)"),
                   DEFAULT_BENCH_SCALING),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-printer=(console|plot)",
         strprintf(_("Choose printer format. console: print data to console. "
                     "plot: Print results as HTML graph (default: %s)"),
                   DEFAULT_BENCH_PRINTER),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-plot-plotlyurl=<uri>",
                  strprintf(_("URL to use for plotly.js (default: %s)"),
                            DEFAULT_PLOT_PLOTLYURL),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-plot-width=<x>",
         strprintf(_("Plot width in pixel (default: %u)"), DEFAULT_PLOT_WIDTH),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-plot-height=<x>",
         strprintf(_("Plot height in pixel (default: %u)"), DEFAULT_PLOT_HEIGHT),
         false, OptionsCategory::OPTIONS);
+
+    // Hidden
+    gArgs.AddArg("-h", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-help", "", false, OptionsCategory::HIDDEN);
 }
 
 int main(int argc, char **argv) {
     SetupBenchArgs();
-    gArgs.ParseParameters(argc, argv);
+    std::string error;
+    if (!gArgs.ParseParameters(argc, argv, error)) {
+        fprintf(stderr, "Error parsing command line arguments: %s\n",
+                error.c_str());
+        return false;
+    }
 
     if (HelpRequested(gArgs)) {
         std::cout << gArgs.GetHelpMessage();
         return 0;
     }
 
     SHA256AutoDetect();
     RandomInit();
     ECC_Start();
     SetupEnvironment();
 
     // don't want to write to debug.log file
     GetLogger().m_print_to_file = false;
 
     int64_t evaluations = gArgs.GetArg("-evals", DEFAULT_BENCH_EVALUATIONS);
     std::string regex_filter = gArgs.GetArg("-filter", DEFAULT_BENCH_FILTER);
     std::string scaling_str = gArgs.GetArg("-scaling", DEFAULT_BENCH_SCALING);
     bool is_list_only = gArgs.GetBoolArg("-list", false);
 
     double scaling_factor = boost::lexical_cast<double>(scaling_str);
 
     std::unique_ptr<benchmark::Printer> printer(
         new benchmark::ConsolePrinter());
     std::string printer_arg = gArgs.GetArg("-printer", DEFAULT_BENCH_PRINTER);
     if ("plot" == printer_arg) {
         printer.reset(new benchmark::PlotlyPrinter(
             gArgs.GetArg("-plot-plotlyurl", DEFAULT_PLOT_PLOTLYURL),
             gArgs.GetArg("-plot-width", DEFAULT_PLOT_WIDTH),
             gArgs.GetArg("-plot-height", DEFAULT_PLOT_HEIGHT)));
     }
 
     benchmark::BenchRunner::RunAll(*printer, evaluations, scaling_factor,
                                    regex_filter, is_list_only);
 
     ECC_Stop();
 }
diff --git a/src/bitcoin-cli.cpp b/src/bitcoin-cli.cpp
index 13a31a284..eece0c66b 100644
--- a/src/bitcoin-cli.cpp
+++ b/src/bitcoin-cli.cpp
@@ -1,618 +1,631 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <chainparamsbase.h>
 #include <clientversion.h>
 #include <fs.h>
 #include <rpc/client.h>
 #include <rpc/protocol.h>
 #include <support/events.h>
 #include <util.h>
 #include <utilstrencodings.h>
 
 #include <event2/buffer.h>
 #include <event2/keyvalq_struct.h>
 
 #include <univalue.h>
 
 #include <cstdio>
 
 static const char DEFAULT_RPCCONNECT[] = "127.0.0.1";
 static const int DEFAULT_HTTP_CLIENT_TIMEOUT = 900;
 static const bool DEFAULT_NAMED = false;
 static const int CONTINUE_EXECUTION = -1;
 
 static void SetupCliArgs() {
     const auto defaultBaseParams =
         CreateBaseChainParams(CBaseChainParams::MAIN);
     const auto testnetBaseParams =
         CreateBaseChainParams(CBaseChainParams::TESTNET);
 
     gArgs.AddArg("-?", _("This help message"), false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-conf=<file>",
                  strprintf(_("Specify configuration file (default: %s)"),
                            BITCOIN_CONF_FILENAME),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-datadir=<dir>", _("Specify data directory"), false,
                  OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-getinfo",
         _("Get general information from the remote server. Note that unlike "
           "server-side RPC calls, the results of -getinfo is the result of "
           "multiple non-atomic requests. Some entries in the result may "
           "represent results from different states (e.g. wallet balance may be "
           "as of a different block from the chain state reported)"),
         false, OptionsCategory::OPTIONS);
     SetupChainParamsBaseOptions();
     gArgs.AddArg(
         "-named",
         strprintf(_("Pass named instead of positional arguments (default: %s)"),
                   DEFAULT_NAMED),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-rpcconnect=<ip>",
         strprintf(_("Send commands to node running on <ip> (default: %s)"),
                   DEFAULT_RPCCONNECT),
         false, OptionsCategory::OPTIONS);
+    gArgs.AddArg(
+        "-rpccookiefile=<loc>",
+        _("Location of the auth cookie. Relative paths will be prefixed by a "
+          "net-specific datadir location. (default: data dir)"),
+        false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-rpcport=<port>",
         strprintf(
             _("Connect to JSON-RPC on <port> (default: %u or testnet: %u)"),
             defaultBaseParams->RPCPort(), testnetBaseParams->RPCPort()),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-rpcwait", _("Wait for RPC server to start"), false,
                  OptionsCategory::OPTIONS);
     gArgs.AddArg("-rpcuser=<user>", _("Username for JSON-RPC connections"),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-rpcpassword=<pw>", _("Password for JSON-RPC connections"),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-rpcclienttimeout=<n>",
                  strprintf(_("Timeout in seconds during HTTP requests, or 0 "
                              "for no timeout. (default: %d)"),
                            DEFAULT_HTTP_CLIENT_TIMEOUT),
                  false, OptionsCategory::OPTIONS);
 
     gArgs.AddArg(
         "-stdinrpcpass",
         strprintf(_("Read RPC password from standard input as a single line. "
                     "When combined with -stdin, the first line from standard "
                     "input is used for the RPC password.")),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-stdin",
                  _("Read extra arguments from standard input, one per line "
                    "until EOF/Ctrl-D (recommended for sensitive information "
                    "such as passphrases)"),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-rpcwallet=<walletname>",
         _("Send RPC for non-default wallet on RPC server (needs to exactly "
           "match corresponding -wallet option passed to bitcoind)"),
         false, OptionsCategory::OPTIONS);
+
+    // Hidden
+    gArgs.AddArg("-h", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-help", "", false, OptionsCategory::HIDDEN);
 }
 
 //////////////////////////////////////////////////////////////////////////////
 //
 // Start
 //
 
 //
 // Exception thrown on connection error.  This error is used to determine when
 // to wait if -rpcwait is given.
 //
 class CConnectionFailed : public std::runtime_error {
 public:
     explicit inline CConnectionFailed(const std::string &msg)
         : std::runtime_error(msg) {}
 };
 
 //
 // This function returns either one of EXIT_ codes when it's expected to stop
 // the process or CONTINUE_EXECUTION when it's expected to continue further.
 //
 static int AppInitRPC(int argc, char *argv[]) {
     //
     // Parameters
     //
     SetupCliArgs();
-    gArgs.ParseParameters(argc, argv);
+    std::string error;
+    if (!gArgs.ParseParameters(argc, argv, error)) {
+        fprintf(stderr, "Error parsing command line arguments: %s\n",
+                error.c_str());
+        return EXIT_FAILURE;
+    }
     if (argc < 2 || HelpRequested(gArgs) || gArgs.IsArgSet("-version")) {
         std::string strUsage =
             PACKAGE_NAME " RPC client version " + FormatFullVersion() + "\n";
         if (!gArgs.IsArgSet("-version")) {
             strUsage += "\n"
                         "Usage:  bitcoin-cli [options] <command> [params]  "
                         "Send command to " PACKAGE_NAME "\n"
                         "or:     bitcoin-cli [options] -named <command> "
                         "[name=value]...  Send command to " PACKAGE_NAME
                         " (with named arguments)\n"
                         "or:     bitcoin-cli [options] help                "
                         "List commands\n"
                         "or:     bitcoin-cli [options] help <command>      Get "
                         "help for a command\n";
 
             strUsage += "\n" + gArgs.GetHelpMessage();
         }
 
         fprintf(stdout, "%s", strUsage.c_str());
         if (argc < 2) {
             fprintf(stderr, "Error: too few parameters\n");
             return EXIT_FAILURE;
         }
         return EXIT_SUCCESS;
     }
     if (!fs::is_directory(GetDataDir(false))) {
         fprintf(stderr,
                 "Error: Specified data directory \"%s\" does not exist.\n",
                 gArgs.GetArg("-datadir", "").c_str());
         return EXIT_FAILURE;
     }
-    try {
-        gArgs.ReadConfigFiles();
-    } catch (const std::exception &e) {
-        fprintf(stderr, "Error reading configuration file: %s\n", e.what());
+    if (!gArgs.ReadConfigFiles(error, true)) {
+        fprintf(stderr, "Error reading configuration file: %s\n",
+                error.c_str());
         return EXIT_FAILURE;
     }
     // Check for -testnet or -regtest parameter (BaseParams() calls are only
     // valid after this clause)
     try {
         SelectBaseParams(gArgs.GetChainName());
     } catch (const std::exception &e) {
         fprintf(stderr, "Error: %s\n", e.what());
         return EXIT_FAILURE;
     }
     if (gArgs.GetBoolArg("-rpcssl", false)) {
         fprintf(stderr,
                 "Error: SSL mode for RPC (-rpcssl) is no longer supported.\n");
         return EXIT_FAILURE;
     }
     return CONTINUE_EXECUTION;
 }
 
 /** Reply structure for request_done to fill in */
 struct HTTPReply {
     HTTPReply() : status(0), error(-1) {}
 
     int status;
     int error;
     std::string body;
 };
 
 static const char *http_errorstring(int code) {
     switch (code) {
 #if LIBEVENT_VERSION_NUMBER >= 0x02010300
         case EVREQ_HTTP_TIMEOUT:
             return "timeout reached";
         case EVREQ_HTTP_EOF:
             return "EOF reached";
         case EVREQ_HTTP_INVALID_HEADER:
             return "error while reading header, or invalid header";
         case EVREQ_HTTP_BUFFER_ERROR:
             return "error encountered while reading or writing";
         case EVREQ_HTTP_REQUEST_CANCEL:
             return "request was canceled";
         case EVREQ_HTTP_DATA_TOO_LONG:
             return "response body is larger than allowed";
 #endif
         default:
             return "unknown";
     }
 }
 
 static void http_request_done(struct evhttp_request *req, void *ctx) {
     HTTPReply *reply = static_cast<HTTPReply *>(ctx);
 
     if (req == nullptr) {
         /**
          * If req is nullptr, it means an error occurred while connecting: the
          * error code will have been passed to http_error_cb.
          */
         reply->status = 0;
         return;
     }
 
     reply->status = evhttp_request_get_response_code(req);
 
     struct evbuffer *buf = evhttp_request_get_input_buffer(req);
     if (buf) {
         size_t size = evbuffer_get_length(buf);
         const char *data = (const char *)evbuffer_pullup(buf, size);
         if (data) reply->body = std::string(data, size);
         evbuffer_drain(buf, size);
     }
 }
 
 #if LIBEVENT_VERSION_NUMBER >= 0x02010300
 static void http_error_cb(enum evhttp_request_error err, void *ctx) {
     HTTPReply *reply = static_cast<HTTPReply *>(ctx);
     reply->error = err;
 }
 #endif
 
 /**
  * Class that handles the conversion from a command-line to a JSON-RPC request,
  * as well as converting back to a JSON object that can be shown as result.
  */
 class BaseRequestHandler {
 public:
     virtual ~BaseRequestHandler() {}
     virtual UniValue PrepareRequest(const std::string &method,
                                     const std::vector<std::string> &args) = 0;
     virtual UniValue ProcessReply(const UniValue &batch_in) = 0;
 };
 
 /** Process getinfo requests */
 class GetinfoRequestHandler : public BaseRequestHandler {
 public:
     const int ID_NETWORKINFO = 0;
     const int ID_BLOCKCHAININFO = 1;
     const int ID_WALLETINFO = 2;
 
     /** Create a simulated `getinfo` request. */
     UniValue PrepareRequest(const std::string &method,
                             const std::vector<std::string> &args) override {
         if (!args.empty()) {
             throw std::runtime_error("-getinfo takes no arguments");
         }
         UniValue result(UniValue::VARR);
         result.push_back(
             JSONRPCRequestObj("getnetworkinfo", NullUniValue, ID_NETWORKINFO));
         result.push_back(JSONRPCRequestObj("getblockchaininfo", NullUniValue,
                                            ID_BLOCKCHAININFO));
         result.push_back(
             JSONRPCRequestObj("getwalletinfo", NullUniValue, ID_WALLETINFO));
         return result;
     }
 
     /** Collect values from the batch and form a simulated `getinfo` reply. */
     UniValue ProcessReply(const UniValue &batch_in) override {
         UniValue result(UniValue::VOBJ);
         std::vector<UniValue> batch = JSONRPCProcessBatchReply(batch_in, 3);
         // Errors in getnetworkinfo() and getblockchaininfo() are fatal, pass
         // them on getwalletinfo() is allowed to fail in case there is no
         // wallet.
         if (!batch[ID_NETWORKINFO]["error"].isNull()) {
             return batch[ID_NETWORKINFO];
         }
         if (!batch[ID_BLOCKCHAININFO]["error"].isNull()) {
             return batch[ID_BLOCKCHAININFO];
         }
         result.pushKV("version", batch[ID_NETWORKINFO]["result"]["version"]);
         result.pushKV("protocolversion",
                       batch[ID_NETWORKINFO]["result"]["protocolversion"]);
         if (!batch[ID_WALLETINFO].isNull()) {
             result.pushKV("walletversion",
                           batch[ID_WALLETINFO]["result"]["walletversion"]);
             result.pushKV("balance", batch[ID_WALLETINFO]["result"]["balance"]);
         }
         result.pushKV("blocks", batch[ID_BLOCKCHAININFO]["result"]["blocks"]);
         result.pushKV("timeoffset",
                       batch[ID_NETWORKINFO]["result"]["timeoffset"]);
         result.pushKV("connections",
                       batch[ID_NETWORKINFO]["result"]["connections"]);
         result.pushKV("proxy",
                       batch[ID_NETWORKINFO]["result"]["networks"][0]["proxy"]);
         result.pushKV("difficulty",
                       batch[ID_BLOCKCHAININFO]["result"]["difficulty"]);
         result.pushKV(
             "testnet",
             UniValue(batch[ID_BLOCKCHAININFO]["result"]["chain"].get_str() ==
                      "test"));
         if (!batch[ID_WALLETINFO].isNull()) {
             result.pushKV("walletversion",
                           batch[ID_WALLETINFO]["result"]["walletversion"]);
             result.pushKV("balance", batch[ID_WALLETINFO]["result"]["balance"]);
             result.pushKV("keypoololdest",
                           batch[ID_WALLETINFO]["result"]["keypoololdest"]);
             result.pushKV("keypoolsize",
                           batch[ID_WALLETINFO]["result"]["keypoolsize"]);
             if (!batch[ID_WALLETINFO]["result"]["unlocked_until"].isNull()) {
                 result.pushKV("unlocked_until",
                               batch[ID_WALLETINFO]["result"]["unlocked_until"]);
             }
             result.pushKV("paytxfee",
                           batch[ID_WALLETINFO]["result"]["paytxfee"]);
         }
         result.pushKV("relayfee", batch[ID_NETWORKINFO]["result"]["relayfee"]);
         result.pushKV("warnings", batch[ID_NETWORKINFO]["result"]["warnings"]);
         return JSONRPCReplyObj(result, NullUniValue, 1);
     }
 };
 
 /** Process default single requests */
 class DefaultRequestHandler : public BaseRequestHandler {
 public:
     UniValue PrepareRequest(const std::string &method,
                             const std::vector<std::string> &args) override {
         UniValue params;
         if (gArgs.GetBoolArg("-named", DEFAULT_NAMED)) {
             params = RPCConvertNamedValues(method, args);
         } else {
             params = RPCConvertValues(method, args);
         }
         return JSONRPCRequestObj(method, params, 1);
     }
 
     UniValue ProcessReply(const UniValue &reply) override {
         return reply.get_obj();
     }
 };
 
 static UniValue CallRPC(BaseRequestHandler *rh, const std::string &strMethod,
                         const std::vector<std::string> &args) {
     std::string host;
     // In preference order, we choose the following for the port:
     //     1. -rpcport
     //     2. port in -rpcconnect (ie following : in ipv4 or ]: in ipv6)
     //     3. default port for chain
     int port = BaseParams().RPCPort();
     SplitHostPort(gArgs.GetArg("-rpcconnect", DEFAULT_RPCCONNECT), port, host);
     port = gArgs.GetArg("-rpcport", port);
 
     // Obtain event base
     raii_event_base base = obtain_event_base();
 
     // Synchronously look up hostname
     raii_evhttp_connection evcon =
         obtain_evhttp_connection_base(base.get(), host, port);
     evhttp_connection_set_timeout(
         evcon.get(),
         gArgs.GetArg("-rpcclienttimeout", DEFAULT_HTTP_CLIENT_TIMEOUT));
 
     HTTPReply response;
     raii_evhttp_request req =
         obtain_evhttp_request(http_request_done, (void *)&response);
     if (req == nullptr) throw std::runtime_error("create http request failed");
 #if LIBEVENT_VERSION_NUMBER >= 0x02010300
     evhttp_request_set_error_cb(req.get(), http_error_cb);
 #endif
 
     // Get credentials
     std::string strRPCUserColonPass;
     bool failedToGetAuthCookie = false;
     if (gArgs.GetArg("-rpcpassword", "") == "") {
         // Try fall back to cookie-based authentication if no password is
         // provided
         if (!GetAuthCookie(&strRPCUserColonPass)) {
             failedToGetAuthCookie = true;
         }
     } else {
         strRPCUserColonPass = gArgs.GetArg("-rpcuser", "") + ":" +
                               gArgs.GetArg("-rpcpassword", "");
     }
 
     struct evkeyvalq *output_headers =
         evhttp_request_get_output_headers(req.get());
     assert(output_headers);
     evhttp_add_header(output_headers, "Host", host.c_str());
     evhttp_add_header(output_headers, "Connection", "close");
     evhttp_add_header(
         output_headers, "Authorization",
         (std::string("Basic ") + EncodeBase64(strRPCUserColonPass)).c_str());
 
     // Attach request data
     std::string strRequest = rh->PrepareRequest(strMethod, args).write() + "\n";
     struct evbuffer *output_buffer =
         evhttp_request_get_output_buffer(req.get());
     assert(output_buffer);
     evbuffer_add(output_buffer, strRequest.data(), strRequest.size());
 
     // check if we should use a special wallet endpoint
     std::string endpoint = "/";
     if (!gArgs.GetArgs("-rpcwallet").empty()) {
         std::string walletName = gArgs.GetArg("-rpcwallet", "");
         char *encodedURI =
             evhttp_uriencode(walletName.c_str(), walletName.size(), false);
         if (encodedURI) {
             endpoint = "/wallet/" + std::string(encodedURI);
             free(encodedURI);
         } else {
             throw CConnectionFailed("uri-encode failed");
         }
     }
     int r = evhttp_make_request(evcon.get(), req.get(), EVHTTP_REQ_POST,
                                 endpoint.c_str());
     // ownership moved to evcon in above call
     req.release();
     if (r != 0) {
         throw CConnectionFailed("send http request failed");
     }
 
     event_base_dispatch(base.get());
 
     if (response.status == 0) {
         std::string responseErrorMessage;
         if (response.error != -1) {
             responseErrorMessage =
                 strprintf(" (error code %d - \"%s\")", response.error,
                           http_errorstring(response.error));
         }
         throw CConnectionFailed(
             strprintf("Could not connect to the server %s:%d%s\n\nMake sure "
                       "the bitcoind server is running and that you are "
                       "connecting to the correct RPC port.",
                       host, port, responseErrorMessage));
     } else if (response.status == HTTP_UNAUTHORIZED) {
         if (failedToGetAuthCookie) {
             throw std::runtime_error(strprintf(
                 _("Could not locate RPC credentials. No authentication cookie "
                   "could be found, and RPC password is not set.  See "
                   "-rpcpassword and -stdinrpcpass.  Configuration file: (%s)"),
                 GetConfigFile(gArgs.GetArg("-conf", BITCOIN_CONF_FILENAME))
                     .string()
                     .c_str()));
         } else {
             throw std::runtime_error(
                 "Authorization failed: Incorrect rpcuser or rpcpassword");
         }
     } else if (response.status >= 400 && response.status != HTTP_BAD_REQUEST &&
                response.status != HTTP_NOT_FOUND &&
                response.status != HTTP_INTERNAL_SERVER_ERROR) {
         throw std::runtime_error(
             strprintf("server returned HTTP error %d", response.status));
     } else if (response.body.empty()) {
         throw std::runtime_error("no response from server");
     }
 
     // Parse reply
     UniValue valReply(UniValue::VSTR);
     if (!valReply.read(response.body)) {
         throw std::runtime_error("couldn't parse reply from server");
     }
     const UniValue reply = rh->ProcessReply(valReply);
     if (reply.empty()) {
         throw std::runtime_error(
             "expected reply to have result, error and id properties");
     }
 
     return reply;
 }
 
 static int CommandLineRPC(int argc, char *argv[]) {
     std::string strPrint;
     int nRet = 0;
     try {
         // Skip switches
         while (argc > 1 && IsSwitchChar(argv[1][0])) {
             argc--;
             argv++;
         }
         std::string rpcPass;
         if (gArgs.GetBoolArg("-stdinrpcpass", false)) {
             if (!std::getline(std::cin, rpcPass))
                 throw std::runtime_error("-stdinrpcpass specified but failed "
                                          "to read from standard input");
             gArgs.ForceSetArg("-rpcpassword", rpcPass);
         }
         std::vector<std::string> args =
             std::vector<std::string>(&argv[1], &argv[argc]);
         if (gArgs.GetBoolArg("-stdin", false)) {
             // Read one arg per line from stdin and append
             std::string line;
             while (std::getline(std::cin, line)) {
                 args.push_back(line);
             }
         }
         std::unique_ptr<BaseRequestHandler> rh;
         std::string method;
         if (gArgs.GetBoolArg("-getinfo", false)) {
             rh.reset(new GetinfoRequestHandler());
             method = "";
         } else {
             rh.reset(new DefaultRequestHandler());
             if (args.size() < 1) {
                 throw std::runtime_error(
                     "too few parameters (need at least command)");
             }
             method = args[0];
             // Remove trailing method name from arguments vector
             args.erase(args.begin());
         }
 
         // Execute and handle connection failures with -rpcwait
         const bool fWait = gArgs.GetBoolArg("-rpcwait", false);
         do {
             try {
                 const UniValue reply = CallRPC(rh.get(), method, args);
 
                 // Parse reply
                 const UniValue &result = find_value(reply, "result");
                 const UniValue &error = find_value(reply, "error");
 
                 if (!error.isNull()) {
                     // Error
                     int code = error["code"].get_int();
                     if (fWait && code == RPC_IN_WARMUP)
                         throw CConnectionFailed("server in warmup");
                     strPrint = "error: " + error.write();
                     nRet = abs(code);
                     if (error.isObject()) {
                         UniValue errCode = find_value(error, "code");
                         UniValue errMsg = find_value(error, "message");
                         strPrint =
                             errCode.isNull()
                                 ? ""
                                 : "error code: " + errCode.getValStr() + "\n";
 
                         if (errMsg.isStr()) {
                             strPrint += "error message:\n" + errMsg.get_str();
                         }
 
                         if (errCode.isNum() &&
                             errCode.get_int() == RPC_WALLET_NOT_SPECIFIED) {
                             strPrint += "\nTry adding "
                                         "\"-rpcwallet=<filename>\" option to "
                                         "bitcoin-cli command line.";
                         }
                     }
                 } else {
                     // Result
                     if (result.isNull()) {
                         strPrint = "";
                     } else if (result.isStr()) {
                         strPrint = result.get_str();
                     } else {
                         strPrint = result.write(2);
                     }
                 }
                 // Connection succeeded, no need to retry.
                 break;
             } catch (const CConnectionFailed &) {
                 if (fWait) {
                     MilliSleep(1000);
                 } else {
                     throw;
                 }
             }
         } while (fWait);
     } catch (const boost::thread_interrupted &) {
         throw;
     } catch (const std::exception &e) {
         strPrint = std::string("error: ") + e.what();
         nRet = EXIT_FAILURE;
     } catch (...) {
         PrintExceptionContinue(nullptr, "CommandLineRPC()");
         throw;
     }
 
     if (strPrint != "") {
         fprintf((nRet == 0 ? stdout : stderr), "%s\n", strPrint.c_str());
     }
     return nRet;
 }
 
 int main(int argc, char *argv[]) {
     SetupEnvironment();
     if (!SetupNetworking()) {
         fprintf(stderr, "Error: Initializing networking failed\n");
         return EXIT_FAILURE;
     }
 
     try {
         int ret = AppInitRPC(argc, argv);
         if (ret != CONTINUE_EXECUTION) {
             return ret;
         }
     } catch (const std::exception &e) {
         PrintExceptionContinue(&e, "AppInitRPC()");
         return EXIT_FAILURE;
     } catch (...) {
         PrintExceptionContinue(nullptr, "AppInitRPC()");
         return EXIT_FAILURE;
     }
 
     int ret = EXIT_FAILURE;
     try {
         ret = CommandLineRPC(argc, argv);
     } catch (const std::exception &e) {
         PrintExceptionContinue(&e, "CommandLineRPC()");
     } catch (...) {
         PrintExceptionContinue(nullptr, "CommandLineRPC()");
     }
     return ret;
 }
diff --git a/src/bitcoin-tx.cpp b/src/bitcoin-tx.cpp
index 63cd6d6bc..cbfca8044 100644
--- a/src/bitcoin-tx.cpp
+++ b/src/bitcoin-tx.cpp
@@ -1,873 +1,882 @@
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <chainparams.h>
 #include <clientversion.h>
 #include <coins.h>
 #include <consensus/consensus.h>
 #include <core_io.h>
 #include <key_io.h>
 #include <keystore.h>
 #include <policy/policy.h>
 #include <primitives/transaction.h>
 #include <script/script.h>
 #include <script/sign.h>
 #include <util.h>
 #include <utilmoneystr.h>
 #include <utilstrencodings.h>
 
 #include <boost/algorithm/string.hpp>
 
 #include <univalue.h>
 
 #include <cstdio>
 
 static bool fCreateBlank;
 static std::map<std::string, UniValue> registers;
 static const int CONTINUE_EXECUTION = -1;
 
 static void SetupBitcoinTxArgs() {
     gArgs.AddArg("-?", _("This help message"), false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-create", _("Create new, empty TX."), false,
                  OptionsCategory::OPTIONS);
     gArgs.AddArg("-json", _("Select JSON output"), false,
                  OptionsCategory::OPTIONS);
     gArgs.AddArg("-txid",
                  _("Output only the hex-encoded transaction id of the "
                    "resultant transaction."),
                  false, OptionsCategory::OPTIONS);
     SetupChainParamsBaseOptions();
 
     gArgs.AddArg("delin=N", _("Delete input N from TX"), false,
                  OptionsCategory::COMMANDS);
     gArgs.AddArg("delout=N", _("Delete output N from TX"), false,
                  OptionsCategory::COMMANDS);
     gArgs.AddArg("in=TXID:VOUT(:SEQUENCE_NUMBER)", _("Add input to TX"), false,
                  OptionsCategory::COMMANDS);
     gArgs.AddArg("locktime=N", _("Set TX lock time to N"), false,
                  OptionsCategory::COMMANDS);
     gArgs.AddArg("nversion=N", _("Set TX version to N"), false,
                  OptionsCategory::COMMANDS);
     gArgs.AddArg("outaddr=VALUE:ADDRESS", _("Add address-based output to TX"),
                  false, OptionsCategory::COMMANDS);
     gArgs.AddArg("outpubkey=VALUE:PUBKEY[:FLAGS]",
                  _("Add pay-to-pubkey output to TX") + ". " +
                      _("Optionally add the \"S\" flag to wrap the output in a "
                        "pay-to-script-hash."),
                  false, OptionsCategory::COMMANDS);
     gArgs.AddArg("outdata=[VALUE:]DATA", _("Add data-based output to TX"),
                  false, OptionsCategory::COMMANDS);
     gArgs.AddArg("outscript=VALUE:SCRIPT[:FLAGS]",
                  _("Add raw script output to TX") + ". " +
                      _("Optionally add the \"S\" flag to wrap the output in a "
                        "pay-to-script-hash."),
                  false, OptionsCategory::COMMANDS);
     gArgs.AddArg(
         "outmultisig=VALUE:REQUIRED:PUBKEYS:PUBKEY1:PUBKEY2:....[:FLAGS]",
         _("Add Pay To n-of-m Multi-sig output to TX. n = REQUIRED, m = "
           "PUBKEYS") +
             ". " +
             _("Optionally add the \"S\" flag to wrap the output in a "
               "pay-to-script-hash."),
         false, OptionsCategory::COMMANDS);
     gArgs.AddArg("sign=SIGHASH-FLAGS",
                  _("Add zero or more signatures to transaction") + ". " +
                      _("This command requires JSON registers:") +
                      _("prevtxs=JSON object") + ", " +
                      _("privatekeys=JSON object") + ". " +
                      _("See signrawtransaction docs for format of sighash "
                        "flags, JSON objects."),
                  false, OptionsCategory::COMMANDS);
 
     gArgs.AddArg("load=NAME:FILENAME",
                  _("Load JSON file FILENAME into register NAME"), false,
                  OptionsCategory::REGISTER_COMMANDS);
     gArgs.AddArg("set=NAME:JSON-STRING",
                  _("Set register NAME to given JSON-STRING"), false,
                  OptionsCategory::REGISTER_COMMANDS);
+
+    // Hidden
+    gArgs.AddArg("-h", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-help", "", false, OptionsCategory::HIDDEN);
 }
 
 //
 // This function returns either one of EXIT_ codes when it's expected to stop
 // the process or CONTINUE_EXECUTION when it's expected to continue further.
 //
 static int AppInitRawTx(int argc, char *argv[]) {
     //
     // Parameters
     //
     SetupBitcoinTxArgs();
-    gArgs.ParseParameters(argc, argv);
+    std::string error;
+    if (!gArgs.ParseParameters(argc, argv, error)) {
+        fprintf(stderr, "Error parsing command line arguments: %s\n",
+                error.c_str());
+        return EXIT_FAILURE;
+    }
 
     // Check for -testnet or -regtest parameter (Params() calls are only valid
     // after this clause)
     try {
         SelectParams(gArgs.GetChainName());
     } catch (const std::exception &e) {
         fprintf(stderr, "Error: %s\n", e.what());
         return EXIT_FAILURE;
     }
 
     fCreateBlank = gArgs.GetBoolArg("-create", false);
 
     if (argc < 2 || HelpRequested(gArgs)) {
         // First part of help message is specific to this utility
         std::string strUsage =
             PACKAGE_NAME " bitcoin-tx utility version " + FormatFullVersion() +
             "\n\n" +
             "Usage:  bitcoin-tx [options] <hex-tx> [commands]  Update "
             "hex-encoded bitcoin transaction\n" +
             "or:     bitcoin-tx [options] -create [commands]   Create "
             "hex-encoded bitcoin transaction\n" +
             "\n";
 
         strUsage += gArgs.GetHelpMessage();
         fprintf(stdout, "%s", strUsage.c_str());
 
         if (argc < 2) {
             fprintf(stderr, "Error: too few parameters\n");
             return EXIT_FAILURE;
         }
 
         return EXIT_SUCCESS;
     }
 
     return CONTINUE_EXECUTION;
 }
 
 static void RegisterSetJson(const std::string &key,
                             const std::string &rawJson) {
     UniValue val;
     if (!val.read(rawJson)) {
         std::string strErr = "Cannot parse JSON for key " + key;
         throw std::runtime_error(strErr);
     }
 
     registers[key] = val;
 }
 
 static void RegisterSet(const std::string &strInput) {
     // separate NAME:VALUE in string
     size_t pos = strInput.find(':');
     if ((pos == std::string::npos) || (pos == 0) ||
         (pos == (strInput.size() - 1))) {
         throw std::runtime_error("Register input requires NAME:VALUE");
     }
 
     std::string key = strInput.substr(0, pos);
     std::string valStr = strInput.substr(pos + 1, std::string::npos);
 
     RegisterSetJson(key, valStr);
 }
 
 static void RegisterLoad(const std::string &strInput) {
     // separate NAME:FILENAME in string
     size_t pos = strInput.find(':');
     if ((pos == std::string::npos) || (pos == 0) ||
         (pos == (strInput.size() - 1))) {
         throw std::runtime_error("Register load requires NAME:FILENAME");
     }
 
     std::string key = strInput.substr(0, pos);
     std::string filename = strInput.substr(pos + 1, std::string::npos);
 
     FILE *f = fopen(filename.c_str(), "r");
     if (!f) {
         std::string strErr = "Cannot open file " + filename;
         throw std::runtime_error(strErr);
     }
 
     // load file chunks into one big buffer
     std::string valStr;
     while ((!feof(f)) && (!ferror(f))) {
         char buf[4096];
         int bread = fread(buf, 1, sizeof(buf), f);
         if (bread <= 0) {
             break;
         }
 
         valStr.insert(valStr.size(), buf, bread);
     }
 
     int error = ferror(f);
     fclose(f);
 
     if (error) {
         std::string strErr = "Error reading file " + filename;
         throw std::runtime_error(strErr);
     }
 
     // evaluate as JSON buffer register
     RegisterSetJson(key, valStr);
 }
 
 static Amount ExtractAndValidateValue(const std::string &strValue) {
     Amount value;
     if (!ParseMoney(strValue, value)) {
         throw std::runtime_error("invalid TX output value");
     }
 
     return value;
 }
 
 static void MutateTxVersion(CMutableTransaction &tx,
                             const std::string &cmdVal) {
     int64_t newVersion = atoi64(cmdVal);
     if (newVersion < 1 || newVersion > CTransaction::MAX_STANDARD_VERSION) {
         throw std::runtime_error("Invalid TX version requested");
     }
 
     tx.nVersion = int(newVersion);
 }
 
 static void MutateTxLocktime(CMutableTransaction &tx,
                              const std::string &cmdVal) {
     int64_t newLocktime = atoi64(cmdVal);
     if (newLocktime < 0LL || newLocktime > 0xffffffffLL) {
         throw std::runtime_error("Invalid TX locktime requested");
     }
 
     tx.nLockTime = (unsigned int)newLocktime;
 }
 
 static void MutateTxAddInput(CMutableTransaction &tx,
                              const std::string &strInput) {
     std::vector<std::string> vStrInputParts;
     boost::split(vStrInputParts, strInput, boost::is_any_of(":"));
 
     // separate TXID:VOUT in string
     if (vStrInputParts.size() < 2) {
         throw std::runtime_error("TX input missing separator");
     }
 
     // extract and validate TXID
     std::string strTxid = vStrInputParts[0];
     if ((strTxid.size() != 64) || !IsHex(strTxid)) {
         throw std::runtime_error("invalid TX input txid");
     }
 
     TxId txid(uint256S(strTxid));
 
     static const unsigned int minTxOutSz = 9;
     static const unsigned int maxVout = MAX_TX_SIZE / minTxOutSz;
 
     // extract and validate vout
     std::string strVout = vStrInputParts[1];
     int vout = atoi(strVout);
     if ((vout < 0) || (vout > (int)maxVout)) {
         throw std::runtime_error("invalid TX input vout");
     }
 
     // extract the optional sequence number
     uint32_t nSequenceIn = std::numeric_limits<unsigned int>::max();
     if (vStrInputParts.size() > 2) {
         nSequenceIn = std::stoul(vStrInputParts[2]);
     }
 
     // append to transaction input list
     CTxIn txin(txid, vout, CScript(), nSequenceIn);
     tx.vin.push_back(txin);
 }
 
 static void MutateTxAddOutAddr(CMutableTransaction &tx,
                                const std::string &strInput,
                                const CChainParams &chainParams) {
     // Separate into VALUE:ADDRESS
     std::vector<std::string> vStrInputParts;
     boost::split(vStrInputParts, strInput, boost::is_any_of(":"));
 
     if (vStrInputParts.size() != 2) {
         throw std::runtime_error("TX output missing or too many separators");
     }
 
     // Extract and validate VALUE
     Amount value = ExtractAndValidateValue(vStrInputParts[0]);
 
     // extract and validate ADDRESS
     std::string strAddr = vStrInputParts[1];
     CTxDestination destination = DecodeDestination(strAddr, chainParams);
     if (!IsValidDestination(destination)) {
         throw std::runtime_error("invalid TX output address");
     }
     CScript scriptPubKey = GetScriptForDestination(destination);
 
     // construct TxOut, append to transaction output list
     CTxOut txout(value, scriptPubKey);
     tx.vout.push_back(txout);
 }
 
 static void MutateTxAddOutPubKey(CMutableTransaction &tx,
                                  const std::string &strInput) {
     // Separate into VALUE:PUBKEY[:FLAGS]
     std::vector<std::string> vStrInputParts;
     boost::split(vStrInputParts, strInput, boost::is_any_of(":"));
 
     if (vStrInputParts.size() < 2 || vStrInputParts.size() > 3) {
         throw std::runtime_error("TX output missing or too many separators");
     }
 
     // Extract and validate VALUE
     Amount value = ExtractAndValidateValue(vStrInputParts[0]);
 
     // Extract and validate PUBKEY
     CPubKey pubkey(ParseHex(vStrInputParts[1]));
     if (!pubkey.IsFullyValid()) {
         throw std::runtime_error("invalid TX output pubkey");
     }
 
     CScript scriptPubKey = GetScriptForRawPubKey(pubkey);
 
     // Extract and validate FLAGS
     bool bScriptHash = false;
     if (vStrInputParts.size() == 3) {
         std::string flags = vStrInputParts[2];
         bScriptHash = (flags.find("S") != std::string::npos);
     }
 
     if (bScriptHash) {
         // Get the ID for the script, and then construct a P2SH destination for
         // it.
         scriptPubKey = GetScriptForDestination(CScriptID(scriptPubKey));
     }
 
     // construct TxOut, append to transaction output list
     CTxOut txout(value, scriptPubKey);
     tx.vout.push_back(txout);
 }
 
 static void MutateTxAddOutMultiSig(CMutableTransaction &tx,
                                    const std::string &strInput) {
     // Separate into VALUE:REQUIRED:NUMKEYS:PUBKEY1:PUBKEY2:....[:FLAGS]
     std::vector<std::string> vStrInputParts;
     boost::split(vStrInputParts, strInput, boost::is_any_of(":"));
 
     // Check that there are enough parameters
     if (vStrInputParts.size() < 3) {
         throw std::runtime_error("Not enough multisig parameters");
     }
 
     // Extract and validate VALUE
     Amount value = ExtractAndValidateValue(vStrInputParts[0]);
 
     // Extract REQUIRED
     uint32_t required = stoul(vStrInputParts[1]);
 
     // Extract NUMKEYS
     uint32_t numkeys = stoul(vStrInputParts[2]);
 
     // Validate there are the correct number of pubkeys
     if (vStrInputParts.size() < numkeys + 3) {
         throw std::runtime_error("incorrect number of multisig pubkeys");
     }
 
     if (required < 1 || required > 20 || numkeys < 1 || numkeys > 20 ||
         numkeys < required) {
         throw std::runtime_error("multisig parameter mismatch. Required " +
                                  std::to_string(required) + " of " +
                                  std::to_string(numkeys) + "signatures.");
     }
 
     // extract and validate PUBKEYs
     std::vector<CPubKey> pubkeys;
     for (int pos = 1; pos <= int(numkeys); pos++) {
         CPubKey pubkey(ParseHex(vStrInputParts[pos + 2]));
         if (!pubkey.IsFullyValid()) {
             throw std::runtime_error("invalid TX output pubkey");
         }
 
         pubkeys.push_back(pubkey);
     }
 
     // Extract FLAGS
     bool bScriptHash = false;
     if (vStrInputParts.size() == numkeys + 4) {
         std::string flags = vStrInputParts.back();
         bScriptHash = (flags.find("S") != std::string::npos);
     } else if (vStrInputParts.size() > numkeys + 4) {
         // Validate that there were no more parameters passed
         throw std::runtime_error("Too many parameters");
     }
 
     CScript scriptPubKey = GetScriptForMultisig(required, pubkeys);
 
     if (bScriptHash) {
         // Get the ID for the script, and then construct a P2SH destination for
         // it.
         scriptPubKey = GetScriptForDestination(CScriptID(scriptPubKey));
     }
 
     // construct TxOut, append to transaction output list
     CTxOut txout(value, scriptPubKey);
     tx.vout.push_back(txout);
 }
 
 static void MutateTxAddOutData(CMutableTransaction &tx,
                                const std::string &strInput) {
     Amount value = Amount::zero();
 
     // separate [VALUE:]DATA in string
     size_t pos = strInput.find(':');
 
     if (pos == 0) {
         throw std::runtime_error("TX output value not specified");
     }
 
     if (pos != std::string::npos) {
         // Extract and validate VALUE
         value = ExtractAndValidateValue(strInput.substr(0, pos));
     }
 
     // extract and validate DATA
     std::string strData = strInput.substr(pos + 1, std::string::npos);
 
     if (!IsHex(strData)) {
         throw std::runtime_error("invalid TX output data");
     }
 
     std::vector<uint8_t> data = ParseHex(strData);
 
     CTxOut txout(value, CScript() << OP_RETURN << data);
     tx.vout.push_back(txout);
 }
 
 static void MutateTxAddOutScript(CMutableTransaction &tx,
                                  const std::string &strInput) {
     // separate VALUE:SCRIPT[:FLAGS]
     std::vector<std::string> vStrInputParts;
     boost::split(vStrInputParts, strInput, boost::is_any_of(":"));
     if (vStrInputParts.size() < 2)
         throw std::runtime_error("TX output missing separator");
 
     // Extract and validate VALUE
     Amount value = ExtractAndValidateValue(vStrInputParts[0]);
 
     // extract and validate script
     std::string strScript = vStrInputParts[1];
     CScript scriptPubKey = ParseScript(strScript);
 
     // Extract FLAGS
     bool bScriptHash = false;
     if (vStrInputParts.size() == 3) {
         std::string flags = vStrInputParts.back();
         bScriptHash = (flags.find("S") != std::string::npos);
     }
 
     if (bScriptHash) {
         scriptPubKey = GetScriptForDestination(CScriptID(scriptPubKey));
     }
 
     // construct TxOut, append to transaction output list
     CTxOut txout(value, scriptPubKey);
     tx.vout.push_back(txout);
 }
 
 static void MutateTxDelInput(CMutableTransaction &tx,
                              const std::string &strInIdx) {
     // parse requested deletion index
     int inIdx = atoi(strInIdx);
     if (inIdx < 0 || inIdx >= (int)tx.vin.size()) {
         std::string strErr = "Invalid TX input index '" + strInIdx + "'";
         throw std::runtime_error(strErr.c_str());
     }
 
     // delete input from transaction
     tx.vin.erase(tx.vin.begin() + inIdx);
 }
 
 static void MutateTxDelOutput(CMutableTransaction &tx,
                               const std::string &strOutIdx) {
     // parse requested deletion index
     int outIdx = atoi(strOutIdx);
     if (outIdx < 0 || outIdx >= (int)tx.vout.size()) {
         std::string strErr = "Invalid TX output index '" + strOutIdx + "'";
         throw std::runtime_error(strErr.c_str());
     }
 
     // delete output from transaction
     tx.vout.erase(tx.vout.begin() + outIdx);
 }
 
 static const unsigned int N_SIGHASH_OPTS = 12;
 static const struct {
     const char *flagStr;
     int flags;
 } sigHashOptions[N_SIGHASH_OPTS] = {
     {"ALL", SIGHASH_ALL},
     {"NONE", SIGHASH_NONE},
     {"SINGLE", SIGHASH_SINGLE},
     {"ALL|ANYONECANPAY", SIGHASH_ALL | SIGHASH_ANYONECANPAY},
     {"NONE|ANYONECANPAY", SIGHASH_NONE | SIGHASH_ANYONECANPAY},
     {"SINGLE|ANYONECANPAY", SIGHASH_SINGLE | SIGHASH_ANYONECANPAY},
     {"ALL|FORKID", SIGHASH_ALL | SIGHASH_FORKID},
     {"NONE|FORKID", SIGHASH_NONE | SIGHASH_FORKID},
     {"SINGLE|FORKID", SIGHASH_SINGLE | SIGHASH_FORKID},
     {"ALL|FORKID|ANYONECANPAY",
      SIGHASH_ALL | SIGHASH_FORKID | SIGHASH_ANYONECANPAY},
     {"NONE|FORKID|ANYONECANPAY",
      SIGHASH_NONE | SIGHASH_FORKID | SIGHASH_ANYONECANPAY},
     {"SINGLE|FORKID|ANYONECANPAY",
      SIGHASH_SINGLE | SIGHASH_FORKID | SIGHASH_ANYONECANPAY},
 };
 
 static bool findSigHashFlags(SigHashType &sigHashType,
                              const std::string &flagStr) {
     sigHashType = SigHashType();
 
     for (unsigned int i = 0; i < N_SIGHASH_OPTS; i++) {
         if (flagStr == sigHashOptions[i].flagStr) {
             sigHashType = SigHashType(sigHashOptions[i].flags);
             return true;
         }
     }
 
     return false;
 }
 
 static Amount AmountFromValue(const UniValue &value) {
     if (!value.isNum() && !value.isStr()) {
         throw std::runtime_error("Amount is not a number or string");
     }
 
     int64_t n;
     if (!ParseFixedPoint(value.getValStr(), 8, &n)) {
         throw std::runtime_error("Invalid amount");
     }
     Amount amount = n * SATOSHI;
 
     if (!MoneyRange(amount)) {
         throw std::runtime_error("Amount out of range");
     }
 
     return amount;
 }
 
 static void MutateTxSign(CMutableTransaction &tx, const std::string &flagStr) {
     SigHashType sigHashType = SigHashType().withForkId();
 
     if ((flagStr.size() > 0) && !findSigHashFlags(sigHashType, flagStr)) {
         throw std::runtime_error("unknown sighash flag/sign option");
     }
 
     // mergedTx will end up with all the signatures; it
     // starts as a clone of the raw tx:
     CMutableTransaction mergedTx{tx};
     const CMutableTransaction txv{tx};
 
     CCoinsView viewDummy;
     CCoinsViewCache view(&viewDummy);
 
     if (!registers.count("privatekeys")) {
         throw std::runtime_error("privatekeys register variable must be set.");
     }
 
     CBasicKeyStore tempKeystore;
     UniValue keysObj = registers["privatekeys"];
 
     for (unsigned int kidx = 0; kidx < keysObj.size(); kidx++) {
         if (!keysObj[kidx].isStr()) {
             throw std::runtime_error("privatekey not a std::string");
         }
 
         CKey key = DecodeSecret(keysObj[kidx].getValStr());
         if (!key.IsValid()) {
             throw std::runtime_error("privatekey not valid");
         }
         tempKeystore.AddKey(key);
     }
 
     // Add previous txouts given in the RPC call:
     if (!registers.count("prevtxs")) {
         throw std::runtime_error("prevtxs register variable must be set.");
     }
 
     UniValue prevtxsObj = registers["prevtxs"];
 
     for (unsigned int previdx = 0; previdx < prevtxsObj.size(); previdx++) {
         UniValue prevOut = prevtxsObj[previdx];
         if (!prevOut.isObject()) {
             throw std::runtime_error("expected prevtxs internal object");
         }
 
         std::map<std::string, UniValue::VType> types = {
             {"txid", UniValue::VSTR},
             {"vout", UniValue::VNUM},
             {"scriptPubKey", UniValue::VSTR}};
         if (!prevOut.checkObject(types)) {
             throw std::runtime_error("prevtxs internal object typecheck fail");
         }
 
         TxId txid(ParseHashUV(prevOut["txid"], "txid"));
 
         int nOut = atoi(prevOut["vout"].getValStr());
         if (nOut < 0) {
             throw std::runtime_error("vout must be positive");
         }
 
         COutPoint out(txid, nOut);
         std::vector<uint8_t> pkData(
             ParseHexUV(prevOut["scriptPubKey"], "scriptPubKey"));
         CScript scriptPubKey(pkData.begin(), pkData.end());
 
         {
             const Coin &coin = view.AccessCoin(out);
             if (!coin.IsSpent() &&
                 coin.GetTxOut().scriptPubKey != scriptPubKey) {
                 std::string err("Previous output scriptPubKey mismatch:\n");
                 err = err + ScriptToAsmStr(coin.GetTxOut().scriptPubKey) +
                       "\nvs:\n" + ScriptToAsmStr(scriptPubKey);
                 throw std::runtime_error(err);
             }
 
             CTxOut txout;
             txout.scriptPubKey = scriptPubKey;
             txout.nValue = Amount::zero();
             if (prevOut.exists("amount")) {
                 txout.nValue = AmountFromValue(prevOut["amount"]);
             }
 
             view.AddCoin(out, Coin(txout, 1, false), true);
         }
 
         // If redeemScript given and private keys given, add redeemScript to the
         // tempKeystore so it can be signed:
         if (scriptPubKey.IsPayToScriptHash() &&
             prevOut.exists("redeemScript")) {
             UniValue v = prevOut["redeemScript"];
             std::vector<uint8_t> rsData(ParseHexUV(v, "redeemScript"));
             CScript redeemScript(rsData.begin(), rsData.end());
             tempKeystore.AddCScript(redeemScript);
         }
     }
 
     const CKeyStore &keystore = tempKeystore;
 
     // Sign what we can:
     for (size_t i = 0; i < mergedTx.vin.size(); i++) {
         const CTxIn &txin = mergedTx.vin[i];
         const Coin &coin = view.AccessCoin(txin.prevout);
         if (coin.IsSpent()) {
             continue;
         }
 
         const CScript &prevPubKey = coin.GetTxOut().scriptPubKey;
         const Amount amount = coin.GetTxOut().nValue;
 
         SignatureData sigdata;
         // Only sign SIGHASH_SINGLE if there's a corresponding output:
         if ((sigHashType.getBaseType() != BaseSigHashType::SINGLE) ||
             (i < mergedTx.vout.size())) {
             ProduceSignature(MutableTransactionSignatureCreator(
                                  &keystore, &mergedTx, i, amount, sigHashType),
                              prevPubKey, sigdata);
         }
 
         // ... and merge in other signatures:
         sigdata = CombineSignatures(
             prevPubKey,
             MutableTransactionSignatureChecker(&mergedTx, i, amount), sigdata,
             DataFromTransaction(txv, i));
         UpdateTransaction(mergedTx, i, sigdata);
     }
 
     tx = mergedTx;
 }
 
 class Secp256k1Init {
     ECCVerifyHandle globalVerifyHandle;
 
 public:
     Secp256k1Init() { ECC_Start(); }
     ~Secp256k1Init() { ECC_Stop(); }
 };
 
 static void MutateTx(CMutableTransaction &tx, const std::string &command,
                      const std::string &commandVal,
                      const CChainParams &chainParams) {
     std::unique_ptr<Secp256k1Init> ecc;
 
     if (command == "nversion") {
         MutateTxVersion(tx, commandVal);
     } else if (command == "locktime") {
         MutateTxLocktime(tx, commandVal);
     } else if (command == "delin") {
         MutateTxDelInput(tx, commandVal);
     } else if (command == "in") {
         MutateTxAddInput(tx, commandVal);
     } else if (command == "delout") {
         MutateTxDelOutput(tx, commandVal);
     } else if (command == "outaddr") {
         MutateTxAddOutAddr(tx, commandVal, chainParams);
     } else if (command == "outpubkey") {
         ecc.reset(new Secp256k1Init());
         MutateTxAddOutPubKey(tx, commandVal);
     } else if (command == "outmultisig") {
         ecc.reset(new Secp256k1Init());
         MutateTxAddOutMultiSig(tx, commandVal);
     } else if (command == "outscript") {
         MutateTxAddOutScript(tx, commandVal);
     } else if (command == "outdata") {
         MutateTxAddOutData(tx, commandVal);
     } else if (command == "sign") {
         ecc.reset(new Secp256k1Init());
         MutateTxSign(tx, commandVal);
     } else if (command == "load") {
         RegisterLoad(commandVal);
     } else if (command == "set") {
         RegisterSet(commandVal);
     } else {
         throw std::runtime_error("unknown command");
     }
 }
 
 static void OutputTxJSON(const CTransaction &tx) {
     UniValue entry(UniValue::VOBJ);
     TxToUniv(tx, uint256(), entry);
 
     std::string jsonOutput = entry.write(4);
     fprintf(stdout, "%s\n", jsonOutput.c_str());
 }
 
 static void OutputTxHash(const CTransaction &tx) {
     // the hex-encoded transaction id.
     std::string strHexHash = tx.GetId().GetHex();
 
     fprintf(stdout, "%s\n", strHexHash.c_str());
 }
 
 static void OutputTxHex(const CTransaction &tx) {
     std::string strHex = EncodeHexTx(tx);
 
     fprintf(stdout, "%s\n", strHex.c_str());
 }
 
 static void OutputTx(const CTransaction &tx) {
     if (gArgs.GetBoolArg("-json", false)) {
         OutputTxJSON(tx);
     } else if (gArgs.GetBoolArg("-txid", false)) {
         OutputTxHash(tx);
     } else {
         OutputTxHex(tx);
     }
 }
 
 static std::string readStdin() {
     char buf[4096];
     std::string ret;
 
     while (!feof(stdin)) {
         size_t bread = fread(buf, 1, sizeof(buf), stdin);
         ret.append(buf, bread);
         if (bread < sizeof(buf)) {
             break;
         }
     }
 
     if (ferror(stdin)) {
         throw std::runtime_error("error reading stdin");
     }
 
     boost::algorithm::trim_right(ret);
 
     return ret;
 }
 
 static int CommandLineRawTx(int argc, char *argv[],
                             const CChainParams &chainParams) {
     std::string strPrint;
     int nRet = 0;
     try {
         // Skip switches; Permit common stdin convention "-"
         while (argc > 1 && IsSwitchChar(argv[1][0]) && (argv[1][1] != 0)) {
             argc--;
             argv++;
         }
 
         CMutableTransaction tx;
         int startArg;
 
         if (!fCreateBlank) {
             // require at least one param
             if (argc < 2) {
                 throw std::runtime_error("too few parameters");
             }
 
             // param: hex-encoded bitcoin transaction
             std::string strHexTx(argv[1]);
 
             // "-" implies standard input
             if (strHexTx == "-") {
                 strHexTx = readStdin();
             }
 
             if (!DecodeHexTx(tx, strHexTx)) {
                 throw std::runtime_error("invalid transaction encoding");
             }
 
             startArg = 2;
         } else {
             startArg = 1;
         }
 
         for (int i = startArg; i < argc; i++) {
             std::string arg = argv[i];
             std::string key, value;
             size_t eqpos = arg.find('=');
             if (eqpos == std::string::npos) {
                 key = arg;
             } else {
                 key = arg.substr(0, eqpos);
                 value = arg.substr(eqpos + 1);
             }
 
             MutateTx(tx, key, value, chainParams);
         }
 
         OutputTx(CTransaction(tx));
     }
 
     catch (const boost::thread_interrupted &) {
         throw;
     } catch (const std::exception &e) {
         strPrint = std::string("error: ") + e.what();
         nRet = EXIT_FAILURE;
     } catch (...) {
         PrintExceptionContinue(nullptr, "CommandLineRawTx()");
         throw;
     }
 
     if (strPrint != "") {
         fprintf((nRet == 0 ? stdout : stderr), "%s\n", strPrint.c_str());
     }
 
     return nRet;
 }
 
 int main(int argc, char *argv[]) {
     SetupEnvironment();
 
     try {
         int ret = AppInitRawTx(argc, argv);
         if (ret != CONTINUE_EXECUTION) return ret;
     } catch (const std::exception &e) {
         PrintExceptionContinue(&e, "AppInitRawTx()");
         return EXIT_FAILURE;
     } catch (...) {
         PrintExceptionContinue(nullptr, "AppInitRawTx()");
         return EXIT_FAILURE;
     }
 
     int ret = EXIT_FAILURE;
     try {
         ret = CommandLineRawTx(argc, argv, Params());
     } catch (const std::exception &e) {
         PrintExceptionContinue(&e, "CommandLineRawTx()");
     } catch (...) {
         PrintExceptionContinue(nullptr, "CommandLineRawTx()");
     }
 
     return ret;
 }
diff --git a/src/bitcoind.cpp b/src/bitcoind.cpp
index 52a7c7b27..bb9fbc8c3 100644
--- a/src/bitcoind.cpp
+++ b/src/bitcoind.cpp
@@ -1,219 +1,223 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <chainparams.h>
 #include <clientversion.h>
 #include <compat.h>
 #include <config.h>
 #include <fs.h>
 #include <httprpc.h>
 #include <httpserver.h>
 #include <init.h>
 #include <noui.h>
 #include <rpc/server.h>
 #include <util.h>
 #include <utilstrencodings.h>
 #include <walletinitinterface.h>
 
 #include <cstdio>
 
 /* Introduction text for doxygen: */
 
 /*! \mainpage Developer documentation
  *
  * \section intro_sec Introduction
  *
  * This is the developer documentation of Bitcoin ABC
  * (https://www.bitcoinabc.org/). Bitcoin ABC is a client for the digital
  * currency called Bitcoin Cash (https://www.bitcoincash.org/), which enables
  * instant payments to anyone, anywhere in the world. Bitcoin Cash uses
  * peer-to-peer technology to operate with no central authority: managing
  * transactions and issuing money are carried out collectively by the network.
  *
  * The software is a community-driven open source project, released under the
  * MIT license.
  *
  * \section Navigation
  * Use the buttons <code>Namespaces</code>, <code>Classes</code> or
  * <code>Files</code> at the top of the page to start navigating the code.
  */
 
 static void WaitForShutdown() {
     while (!ShutdownRequested()) {
         MilliSleep(200);
     }
     Interrupt();
 }
 
 //////////////////////////////////////////////////////////////////////////////
 //
 // Start
 //
 static bool AppInit(int argc, char *argv[]) {
     // FIXME: Ideally, we'd like to build the config here, but that's currently
     // not possible as the whole application has too many global state. However,
     // this is a first step.
     auto &config = const_cast<Config &>(GetConfig());
     RPCServer rpcServer;
     HTTPRPCRequestProcessor httpRPCRequestProcessor(config, rpcServer);
 
     bool fRet = false;
 
     //
     // Parameters
     //
     // If Qt is used, parameters/bitcoin.conf are parsed in qt/bitcoin.cpp's
     // main()
     SetupServerArgs();
 #if HAVE_DECL_DAEMON
     gArgs.AddArg("-daemon",
                  _("Run in the background as a daemon and accept commands"),
                  false, OptionsCategory::OPTIONS);
 #endif
-    gArgs.ParseParameters(argc, argv);
+    std::string error;
+    if (!gArgs.ParseParameters(argc, argv, error)) {
+        fprintf(stderr, "Error parsing command line arguments: %s\n",
+                error.c_str());
+        return false;
+    }
 
     // Process help and version before taking care about datadir
     if (HelpRequested(gArgs) || gArgs.IsArgSet("-version")) {
         std::string strUsage =
             PACKAGE_NAME " Daemon version " + FormatFullVersion() + "\n";
 
         if (gArgs.IsArgSet("-version")) {
             strUsage += FormatParagraph(LicenseInfo());
         } else {
             strUsage += "\nUsage:  bitcoind [options]                     "
                         "Start " PACKAGE_NAME " Daemon\n";
 
             strUsage += "\n" + gArgs.GetHelpMessage();
         }
 
         fprintf(stdout, "%s", strUsage.c_str());
         return true;
     }
 
     try {
         if (!fs::is_directory(GetDataDir(false))) {
             fprintf(stderr,
                     "Error: Specified data directory \"%s\" does not exist.\n",
                     gArgs.GetArg("-datadir", "").c_str());
             return false;
         }
-        try {
-            gArgs.ReadConfigFiles();
-        } catch (const std::exception &e) {
-            fprintf(stderr, "Error reading configuration file: %s\n", e.what());
+        if (!gArgs.ReadConfigFiles(error)) {
+            fprintf(stderr, "Error reading configuration file: %s\n",
+                    error.c_str());
             return false;
         }
         // Check for -testnet or -regtest parameter (Params() calls are only
         // valid after this clause)
         try {
             SelectParams(gArgs.GetChainName());
         } catch (const std::exception &e) {
             fprintf(stderr, "Error: %s\n", e.what());
             return false;
         }
 
         // Make sure we create the net-specific data directory early on: if it
         // is new, this has a side effect of also creating
         // <datadir>/<net>/wallets/.
         //
         // TODO: this should be removed once GetDataDir() no longer creates the
         // wallets/ subdirectory.
         // See more info at:
         // https://reviews.bitcoinabc.org/D3312
         GetDataDir(true);
 
         // Error out when loose non-argument tokens are encountered on command
         // line
         for (int i = 1; i < argc; i++) {
             if (!IsSwitchChar(argv[i][0])) {
                 fprintf(stderr,
                         "Error: Command line contains unexpected token '%s', "
                         "see bitcoind -h for a list of options.\n",
                         argv[i]);
                 return false;
             }
         }
 
         // -server defaults to true for bitcoind but not for the GUI so do this
         // here
         gArgs.SoftSetBoolArg("-server", true);
         // Set this early so that parameter interactions go to console
         InitLogging();
         InitParameterInteraction();
         if (!AppInitBasicSetup()) {
             // InitError will have been called with detailed error, which ends
             // up on console
             return false;
         }
         if (!AppInitParameterInteraction(config)) {
             // InitError will have been called with detailed error, which ends
             // up on console
             return false;
         }
         if (!AppInitSanityChecks()) {
             // InitError will have been called with detailed error, which ends
             // up on console
             return false;
         }
         if (gArgs.GetBoolArg("-daemon", false)) {
 #if HAVE_DECL_DAEMON
 #if defined(MAC_OSX)
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 #endif
             fprintf(stdout, "Bitcoin server starting\n");
 
             // Daemonize
             if (daemon(1, 0)) {
                 // don't chdir (1), do close FDs (0)
                 fprintf(stderr, "Error: daemon() failed: %s\n",
                         strerror(errno));
                 return false;
             }
 #if defined(MAC_OSX)
 #pragma GCC diagnostic pop
 #endif
 #else
             fprintf(
                 stderr,
                 "Error: -daemon is not supported on this operating system\n");
             return false;
 #endif // HAVE_DECL_DAEMON
         }
 
         // Lock data directory after daemonization
         if (!AppInitLockDataDirectory()) {
             // If locking the data directory failed, exit immediately
             return false;
         }
         fRet = AppInitMain(config, rpcServer, httpRPCRequestProcessor);
     } catch (const std::exception &e) {
         PrintExceptionContinue(&e, "AppInit()");
     } catch (...) {
         PrintExceptionContinue(nullptr, "AppInit()");
     }
 
     if (!fRet) {
         Interrupt();
     } else {
         WaitForShutdown();
     }
     Shutdown();
 
     return fRet;
 }
 
 int main(int argc, char *argv[]) {
     SetupEnvironment();
 
     // Connect bitcoind signal handlers
     noui_connect();
 
     return (AppInit(argc, argv) ? EXIT_SUCCESS : EXIT_FAILURE);
 }
diff --git a/src/init.cpp b/src/init.cpp
index 5284e8d6a..11a5fb774 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -1,2460 +1,2480 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <init.h>
 
 #include <addrman.h>
 #include <amount.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <checkpoints.h>
 #include <compat/sanity.h>
 #include <config.h>
 #include <consensus/validation.h>
 #include <flatfile.h>
 #include <fs.h>
 #include <httprpc.h>
 #include <httpserver.h>
 #include <index/txindex.h>
 #include <key.h>
 #include <miner.h>
 #include <net.h>
 #include <net_processing.h>
 #include <netbase.h>
 #include <policy/policy.h>
 #include <rpc/blockchain.h>
 #include <rpc/register.h>
 #include <rpc/server.h>
 #include <scheduler.h>
 #include <script/scriptcache.h>
 #include <script/sigcache.h>
 #include <script/standard.h>
 #include <timedata.h>
 #include <torcontrol.h>
 #include <txdb.h>
 #include <txmempool.h>
 #include <ui_interface.h>
 #include <util.h>
 #include <utilmoneystr.h>
 #include <validation.h>
 #include <validationinterface.h>
 #include <walletinitinterface.h>
 #include <warnings.h>
 
 #include <boost/algorithm/string/classification.hpp>
 #include <boost/algorithm/string/replace.hpp>
 #include <boost/algorithm/string/split.hpp>
 #include <boost/bind.hpp>
 #include <boost/interprocess/sync/file_lock.hpp>
 #include <boost/thread.hpp>
 
 #if ENABLE_ZMQ
 #include <zmq/zmqnotificationinterface.h>
 #endif
 
 #ifndef WIN32
 #include <csignal>
 #endif
 #include <cstdint>
 #include <cstdio>
 #include <memory>
 
 static const bool DEFAULT_PROXYRANDOMIZE = true;
 static const bool DEFAULT_REST_ENABLE = false;
 static const bool DEFAULT_STOPAFTERBLOCKIMPORT = false;
 
 std::unique_ptr<CConnman> g_connman;
 std::unique_ptr<PeerLogicValidation> peerLogic;
 
 #if !(ENABLE_WALLET)
 class DummyWalletInit : public WalletInitInterface {
 public:
     void AddWalletOptions() const override {}
     bool ParameterInteraction() const override { return true; }
     void RegisterRPC(CRPCTable &) const override {}
     bool Verify(const CChainParams &chainParams) const override { return true; }
     bool Open(const CChainParams &chainParams) const override {
         LogPrintf("No wallet support compiled in!\n");
         return true;
     }
     void Start(CScheduler &scheduler) const override {}
     void Flush() const override {}
     void Stop() const override {}
     void Close() const override {}
 };
 
 const WalletInitInterface &g_wallet_init_interface = DummyWalletInit();
 #endif
 
 #if ENABLE_ZMQ
 static CZMQNotificationInterface *pzmqNotificationInterface = nullptr;
 #endif
 
 #ifdef WIN32
 // Win32 LevelDB doesn't use filedescriptors, and the ones used for accessing
 // block files don't count towards the fd_set size limit anyway.
 #define MIN_CORE_FILEDESCRIPTORS 0
 #else
 #define MIN_CORE_FILEDESCRIPTORS 150
 #endif
 
 //////////////////////////////////////////////////////////////////////////////
 //
 // Shutdown
 //
 
 //
 // Thread management and startup/shutdown:
 //
 // The network-processing threads are all part of a thread group created by
 // AppInit() or the Qt main() function.
 //
 // A clean exit happens when StartShutdown() or the SIGTERM signal handler sets
 // fRequestShutdown, which triggers the DetectShutdownThread(), which interrupts
 // the main thread group. DetectShutdownThread() then exits, which causes
 // AppInit() to continue (it .joins the shutdown thread). Shutdown() is then
 // called to clean up database connections, and stop other threads that should
 // only be stopped after the main network-processing threads have exited.
 //
 // Shutdown for Qt is very similar, only it uses a QTimer to detect
 // fRequestShutdown getting set, and then does the normal Qt shutdown thing.
 //
 
 std::atomic<bool> fRequestShutdown(false);
 
 void StartShutdown() {
     fRequestShutdown = true;
 }
 bool ShutdownRequested() {
     return fRequestShutdown;
 }
 
 /**
  * This is a minimally invasive approach to shutdown on LevelDB read errors from
  * the chainstate, while keeping user interface out of the common library, which
  * is shared between bitcoind, and bitcoin-qt and non-server tools.
  */
 class CCoinsViewErrorCatcher final : public CCoinsViewBacked {
 public:
     explicit CCoinsViewErrorCatcher(CCoinsView *view)
         : CCoinsViewBacked(view) {}
     bool GetCoin(const COutPoint &outpoint, Coin &coin) const override {
         try {
             return CCoinsViewBacked::GetCoin(outpoint, coin);
         } catch (const std::runtime_error &e) {
             uiInterface.ThreadSafeMessageBox(
                 _("Error reading from database, shutting down."), "",
                 CClientUIInterface::MSG_ERROR);
             LogPrintf("Error reading from database: %s\n", e.what());
             // Starting the shutdown sequence and returning false to the caller
             // would be interpreted as 'entry not found' (as opposed to unable
             // to read data), and could lead to invalid interpretation. Just
             // exit immediately, as we can't continue anyway, and all writes
             // should be atomic.
             abort();
         }
     }
     // Writes do not need similar protection, as failure to write is handled by
     // the caller.
 };
 
 static std::unique_ptr<CCoinsViewErrorCatcher> pcoinscatcher;
 static std::unique_ptr<ECCVerifyHandle> globalVerifyHandle;
 
 static boost::thread_group threadGroup;
 static CScheduler scheduler;
 
 void Interrupt() {
     InterruptHTTPServer();
     InterruptHTTPRPC();
     InterruptRPC();
     InterruptREST();
     InterruptTorControl();
     InterruptMapPort();
     if (g_connman) {
         g_connman->Interrupt();
     }
     if (g_txindex) {
         g_txindex->Interrupt();
     }
 }
 
 void Shutdown() {
     LogPrintf("%s: In progress...\n", __func__);
     static CCriticalSection cs_Shutdown;
     TRY_LOCK(cs_Shutdown, lockShutdown);
     if (!lockShutdown) {
         return;
     }
 
     /// Note: Shutdown() must be able to handle cases in which initialization
     /// failed part of the way, for example if the data directory was found to
     /// be locked. Be sure that anything that writes files or flushes caches
     /// only does this if the respective module was initialized.
     RenameThread("bitcoin-shutoff");
     g_mempool.AddTransactionsUpdated(1);
 
     StopHTTPRPC();
     StopREST();
     StopRPC();
     StopHTTPServer();
     g_wallet_init_interface.Flush();
     StopMapPort();
 
     // Because these depend on each-other, we make sure that neither can be
     // using the other before destroying them.
     if (peerLogic) {
         UnregisterValidationInterface(peerLogic.get());
     }
     if (g_connman) {
         g_connman->Stop();
     }
     if (g_txindex) {
         g_txindex->Stop();
     }
 
     StopTorControl();
 
     // After everything has been shut down, but before things get flushed, stop
     // the CScheduler/checkqueue threadGroup
     threadGroup.interrupt_all();
     threadGroup.join_all();
 
     // After the threads that potentially access these pointers have been
     // stopped, destruct and reset all to nullptr.
     peerLogic.reset();
     g_connman.reset();
     g_txindex.reset();
 
     if (g_is_mempool_loaded &&
         gArgs.GetArg("-persistmempool", DEFAULT_PERSIST_MEMPOOL)) {
         DumpMempool();
     }
 
     // FlushStateToDisk generates a ChainStateFlushed callback, which we should
     // avoid missing
     if (pcoinsTip != nullptr) {
         FlushStateToDisk();
     }
 
     // After there are no more peers/RPC left to give us new data which may
     // generate CValidationInterface callbacks, flush them...
     GetMainSignals().FlushBackgroundCallbacks();
 
     // Any future callbacks will be dropped. This should absolutely be safe - if
     // missing a callback results in an unrecoverable situation, unclean
     // shutdown would too. The only reason to do the above flushes is to let the
     // wallet catch up with our current chain to avoid any strange pruning edge
     // cases and make next startup faster by avoiding rescan.
 
     {
         LOCK(cs_main);
         if (pcoinsTip != nullptr) {
             FlushStateToDisk();
         }
         pcoinsTip.reset();
         pcoinscatcher.reset();
         pcoinsdbview.reset();
         pblocktree.reset();
     }
     g_wallet_init_interface.Stop();
 
 #if ENABLE_ZMQ
     if (pzmqNotificationInterface) {
         UnregisterValidationInterface(pzmqNotificationInterface);
         delete pzmqNotificationInterface;
         pzmqNotificationInterface = nullptr;
     }
 #endif
 
 #ifndef WIN32
     try {
         fs::remove(GetPidFile());
     } catch (const fs::filesystem_error &e) {
         LogPrintf("%s: Unable to remove pidfile: %s\n", __func__, e.what());
     }
 #endif
     UnregisterAllValidationInterfaces();
     GetMainSignals().UnregisterBackgroundSignalScheduler();
     GetMainSignals().UnregisterWithMempoolSignals(g_mempool);
     g_wallet_init_interface.Close();
     globalVerifyHandle.reset();
     ECC_Stop();
     LogPrintf("%s: done\n", __func__);
 }
 
 /**
  * Signal handlers are very limited in what they are allowed to do.
  * The execution context the handler is invoked in is not guaranteed,
  * so we restrict handler operations to just touching variables:
  */
 static void HandleSIGTERM(int) {
     fRequestShutdown = true;
 }
 
 static void HandleSIGHUP(int) {
     GetLogger().m_reopen_file = true;
 }
 
 #ifndef WIN32
 static void registerSignalHandler(int signal, void (*handler)(int)) {
     struct sigaction sa;
     sa.sa_handler = handler;
     sigemptyset(&sa.sa_mask);
     sa.sa_flags = 0;
     sigaction(signal, &sa, NULL);
 }
 #endif
 
 static void OnRPCStarted() {
     uiInterface.NotifyBlockTip.connect(&RPCNotifyBlockChange);
 }
 
 static void OnRPCStopped() {
     uiInterface.NotifyBlockTip.disconnect(&RPCNotifyBlockChange);
     RPCNotifyBlockChange(false, nullptr);
     g_best_block_cv.notify_all();
     LogPrint(BCLog::RPC, "RPC stopped.\n");
 }
 
 void SetupServerArgs() {
     const auto defaultBaseParams =
         CreateBaseChainParams(CBaseChainParams::MAIN);
     const auto testnetBaseParams =
         CreateBaseChainParams(CBaseChainParams::TESTNET);
     const auto defaultChainParams = CreateChainParams(CBaseChainParams::MAIN);
     const auto testnetChainParams =
         CreateChainParams(CBaseChainParams::TESTNET);
 
     // Set all of the args and their help
     // When adding new options to the categories, please keep and ensure
     // alphabetical ordering. Do not translate _(...) -help-debug options, Many
     // technical terms, and only a very small audience, so is unnecessary stress
     // to translators.
     gArgs.AddArg("-?", _("Print this help message and exit"), false,
                  OptionsCategory::OPTIONS);
     gArgs.AddArg("-version", _("Print version and exit"), false,
                  OptionsCategory::OPTIONS);
     gArgs.AddArg("-alertnotify=<cmd>",
                  _("Execute command when a relevant alert is received or we "
                    "see a really long fork (%s in cmd is replaced by message)"),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-assumevalid=<hex>",
         strprintf(
             _("If this block is in the chain assume that it and its ancestors "
               "are valid and potentially skip their script verification (0 to "
               "verify all, default: %s, testnet: %s)"),
             defaultChainParams->GetConsensus().defaultAssumeValid.GetHex(),
             testnetChainParams->GetConsensus().defaultAssumeValid.GetHex()),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-blocksdir=<dir>",
                  _("Specify directory to hold blocks subdirectory for *.dat "
                    "files (default: <datadir>)"),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-blocknotify=<cmd>",
                  _("Execute command when the best block changes (%s in cmd is "
                    "replaced by block hash)"),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-blockreconstructionextratxn=<n>",
         strprintf(_("Extra transactions to keep in memory for compact block "
                     "reconstructions (default: %u)"),
                   DEFAULT_BLOCK_RECONSTRUCTION_EXTRA_TXN),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-blocksonly",
         strprintf(_("Whether to operate in a blocks only mode (default: %d)"),
                   DEFAULT_BLOCKSONLY),
         true, OptionsCategory::OPTIONS);
     gArgs.AddArg("-conf=<file>",
                  strprintf(_("Specify configuration file (default: %s)"),
                            BITCOIN_CONF_FILENAME),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-datadir=<dir>", _("Specify data directory"), false,
                  OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-dbbatchsize",
         strprintf("Maximum database write batch size in bytes (default: %u)",
                   nDefaultDbBatchSize),
         true, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-dbcache=<n>",
         strprintf(
             _("Set database cache size in megabytes (%d to %d, default: %d)"),
             nMinDbCache, nMaxDbCache, nDefaultDbCache),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-debuglogfile=<file>",
         strprintf(
             _("Specify location of debug log file: this can be an absolute "
               "path or a path relative to the data directory (default: %s)"),
             DEFAULT_DEBUGLOGFILE),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-feefilter",
                  strprintf("Tell other nodes to filter invs to us by "
                            "our mempool min fee (default: %d)",
                            DEFAULT_FEEFILTER),
                  true, OptionsCategory::OPTIONS);
     gArgs.AddArg("-finalizationdelay=<n>",
                  strprintf("Set the minimum amount of time to wait between a "
                            "block header reception and the block finalization. "
                            "Unit is seconds (default: %d)",
                            DEFAULT_MIN_FINALIZATION_DELAY),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-includeconf=<file>",
         _("Specify additional configuration file, relative to the -datadir "
           "path (only useable from configuration file, not command line)"),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-maxreorgdepth=<n>",
         strprintf("Configure at what depth blocks are considered final "
                   "(default: %d). Use -1 to disable.",
                   DEFAULT_MAX_REORG_DEPTH),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-loadblock=<file>",
                  _("Imports blocks from external blk000??.dat file on startup"),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-maxmempool=<n>",
                  strprintf(_("Keep the transaction memory pool "
                              "below <n> megabytes (default: %u)"),
                            DEFAULT_MAX_MEMPOOL_SIZE),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-maxorphantx=<n>",
                  strprintf(_("Keep at most <n> unconnectable "
                              "transactions in memory (default: %u)"),
                            DEFAULT_MAX_ORPHAN_TRANSACTIONS),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-mempoolexpiry=<n>",
                  strprintf(_("Do not keep transactions in the mempool "
                              "longer than <n> hours (default: %u)"),
                            DEFAULT_MEMPOOL_EXPIRY),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-minimumchainwork=<hex>",
         strprintf(
             "Minimum work assumed to exist on a valid chain in hex "
             "(default: %s, testnet: %s)",
             defaultChainParams->GetConsensus().nMinimumChainWork.GetHex(),
             testnetChainParams->GetConsensus().nMinimumChainWork.GetHex()),
         true, OptionsCategory::OPTIONS);
     gArgs.AddArg(
         "-par=<n>",
         strprintf(_("Set the number of script verification threads (%u to %d, "
                     "0 = auto, <0 = leave that many cores free, default: %d)"),
                   -GetNumCores(), MAX_SCRIPTCHECK_THREADS,
                   DEFAULT_SCRIPTCHECK_THREADS),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-persistmempool",
                  strprintf(_("Whether to save the mempool on shutdown "
                              "and load on restart (default: %u)"),
                            DEFAULT_PERSIST_MEMPOOL),
                  false, OptionsCategory::OPTIONS);
 #ifndef WIN32
     gArgs.AddArg(
         "-pid=<file>",
         strprintf(_("Specify pid file (default: %s)"), BITCOIN_PID_FILENAME),
         false, OptionsCategory::OPTIONS);
 #endif
     gArgs.AddArg(
         "-prune=<n>",
         strprintf(
             _("Reduce storage requirements by enabling pruning (deleting) of "
               "old blocks. This allows the pruneblockchain RPC to be called to "
               "delete specific blocks, and enables automatic pruning of old "
               "blocks if a target size in MiB is provided. This mode is "
               "incompatible with -txindex and -rescan. "
               "Warning: Reverting this setting requires re-downloading the "
               "entire blockchain. "
               "(default: 0 = disable pruning blocks, 1 = allow manual pruning "
               "via RPC, >%u = automatically prune block files to stay under "
               "the specified target size in MiB)"),
             MIN_DISK_SPACE_FOR_BLOCK_FILES / 1024 / 1024),
         false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-reindex-chainstate",
                  _("Rebuild chain state from the currently indexed blocks"),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-reindex",
                  _("Rebuild chain state and block index from the blk*.dat "
                    "files on disk"),
                  false, OptionsCategory::OPTIONS);
 #ifndef WIN32
     gArgs.AddArg(
         "-sysperms",
         _("Create new files with system default permissions, instead of umask "
           "077 (only effective with disabled wallet functionality)"),
         false, OptionsCategory::OPTIONS);
 #endif
     gArgs.AddArg("-txindex",
                  strprintf(_("Maintain a full transaction index, used by the "
                              "getrawtransaction rpc call (default: %d)"),
                            DEFAULT_TXINDEX),
                  false, OptionsCategory::OPTIONS);
     gArgs.AddArg("-usecashaddr",
                  _("Use Cash Address for destination encoding instead "
                    "of base58 (activate by default on Jan, 14)"),
                  false, OptionsCategory::OPTIONS);
 
     gArgs.AddArg(
         "-addnode=<ip>",
         _("Add a node to connect to and attempt to keep the connection open "
           "(see the `addnode` RPC command help for more info)"),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-banscore=<n>",
         strprintf(
             _("Threshold for disconnecting misbehaving peers (default: %u)"),
             DEFAULT_BANSCORE_THRESHOLD),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-bantime=<n>",
                  strprintf(_("Number of seconds to keep misbehaving peers from "
                              "reconnecting (default: %u)"),
                            DEFAULT_MISBEHAVING_BANTIME),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-bind=<addr>",
                  _("Bind to given address and always listen on it. Use "
                    "[host]:port notation for IPv6"),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-connect=<ip>",
                  _("Connect only to the specified node(s); -connect=0 disables "
                    "automatic connections (the rules for this peer are the "
                    "same as for -addnode)"),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-discover",
                  _("Discover own IP addresses (default: 1 when listening and "
                    "no -externalip or -proxy)"),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-dns",
                  _("Allow DNS lookups for -addnode, -seednode and -connect") +
                      " " + strprintf(_("(default: %d)"), DEFAULT_NAME_LOOKUP),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-dnsseed",
                  _("Query for peer addresses via DNS lookup, if low on "
                    "addresses (default: 1 unless -connect/-noconnect)"),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-externalip=<ip>", _("Specify your own public address"),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-forcednsseed",
         strprintf(
             _("Always query for peer addresses via DNS lookup (default: %d)"),
             DEFAULT_FORCEDNSSEED),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-listen",
                  _("Accept connections from outside (default: 1 if no -proxy "
                    "or -connect/-noconnect)"),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-listenonion",
         strprintf(_("Automatically create Tor hidden service (default: %d)"),
                   DEFAULT_LISTEN_ONION),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-maxconnections=<n>",
         strprintf(_("Maintain at most <n> connections to peers (default: %u)"),
                   DEFAULT_MAX_PEER_CONNECTIONS),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-maxreceivebuffer=<n>",
                  strprintf(_("Maximum per-connection receive buffer, <n>*1000 "
                              "bytes (default: %u)"),
                            DEFAULT_MAXRECEIVEBUFFER),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-maxsendbuffer=<n>",
                  strprintf(_("Maximum per-connection send buffer, <n>*1000 "
                              "bytes (default: %u)"),
                            DEFAULT_MAXSENDBUFFER),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-maxtimeadjustment",
         strprintf(_("Maximum allowed median peer time offset adjustment. Local "
                     "perspective of time may be influenced by peers forward or "
                     "backward by this amount. (default: %u seconds)"),
                   DEFAULT_MAX_TIME_ADJUSTMENT),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-onion=<ip:port>",
                  strprintf(_("Use separate SOCKS5 proxy to reach peers via Tor "
                              "hidden services (default: %s)"),
                            "-proxy"),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-onlynet=<net>",
         _("Only connect to nodes in network <net> (ipv4, ipv6 or onion)"),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-peerbloomfilters",
                  strprintf(_("Support filtering of blocks and transaction with "
                              "bloom filters (default: %d)"),
                            DEFAULT_PEERBLOOMFILTERS),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-permitbaremultisig",
                  strprintf(_("Relay non-P2SH multisig (default: %d)"),
                            DEFAULT_PERMIT_BAREMULTISIG),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-port=<port>",
         strprintf(
             _("Listen for connections on <port> (default: %u or testnet: %u)"),
             defaultChainParams->GetDefaultPort(),
             testnetChainParams->GetDefaultPort()),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-proxy=<ip:port>", _("Connect through SOCKS5 proxy"), false,
                  OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-proxyrandomize",
         strprintf(_("Randomize credentials for every proxy connection. This "
                     "enables Tor stream isolation (default: %d)"),
                   DEFAULT_PROXYRANDOMIZE),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-seednode=<ip>",
         _("Connect to a node to retrieve peer addresses, and disconnect"),
         false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-timeout=<n>",
                  strprintf(_("Specify connection timeout in milliseconds "
                              "(minimum: 1, default: %d)"),
                            DEFAULT_CONNECT_TIMEOUT),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-torcontrol=<ip>:<port>",
                  strprintf(_("Tor control port to use if onion listening "
                              "enabled (default: %s)"),
                            DEFAULT_TOR_CONTROL),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-torpassword=<pass>",
                  _("Tor control port password (default: empty)"), false,
                  OptionsCategory::CONNECTION);
 #ifdef USE_UPNP
 #if USE_UPNP
     gArgs.AddArg("-upnp",
                  _("Use UPnP to map the listening port (default: 1 when "
                    "listening and no -proxy)"),
                  false, OptionsCategory::CONNECTION);
 #else
     gArgs.AddArg(
         "-upnp",
         strprintf(_("Use UPnP to map the listening port (default: %u)"), 0),
         false, OptionsCategory::CONNECTION);
 #endif
 #endif
     gArgs.AddArg("-whitebind=<addr>",
                  _("Bind to given address and whitelist peers connecting to "
                    "it. Use [host]:port notation for IPv6"),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg("-whitelist=<IP address or network>",
                  _("Whitelist peers connecting from the given IP address (e.g. "
                    "1.2.3.4) or CIDR notated network (e.g. 1.2.3.0/24). Can be "
                    "specified multiple times.") +
                      " " +
                      _("Whitelisted peers cannot be DoS banned and their "
                        "transactions are always relayed, even if they are "
                        "already in the mempool, useful e.g. for a gateway"),
                  false, OptionsCategory::CONNECTION);
     gArgs.AddArg(
         "-maxuploadtarget=<n>",
         strprintf(_("Tries to keep outbound traffic under the given target (in "
                     "MiB per 24h), 0 = no limit (default: %d)"),
                   DEFAULT_MAX_UPLOAD_TARGET),
         false, OptionsCategory::CONNECTION);
 
     g_wallet_init_interface.AddWalletOptions();
 
 #if ENABLE_ZMQ
     gArgs.AddArg("-zmqpubhashblock=<address>",
                  _("Enable publish hash block in <address>"), false,
                  OptionsCategory::ZMQ);
     gArgs.AddArg("-zmqpubhashtx=<address>",
                  _("Enable publish hash transaction in <address>"), false,
                  OptionsCategory::ZMQ);
     gArgs.AddArg("-zmqpubrawblock=<address>",
                  _("Enable publish raw block in <address>"), false,
                  OptionsCategory::ZMQ);
     gArgs.AddArg("-zmqpubrawtx=<address>",
                  _("Enable publish raw transaction in <address>"), false,
                  OptionsCategory::ZMQ);
 #endif
 
     gArgs.AddArg(
         "-checkblocks=<n>",
         strprintf(
             _("How many blocks to check at startup (default: %u, 0 = all)"),
             DEFAULT_CHECKBLOCKS),
         true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-checklevel=<n>",
                  strprintf(_("How thorough the block verification of "
                              "-checkblocks is (0-4, default: %u)"),
                            DEFAULT_CHECKLEVEL),
                  true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-checkblockindex",
         strprintf("Do a full consistency check for mapBlockIndex, "
                   "setBlockIndexCandidates, chainActive and mapBlocksUnlinked "
                   "occasionally. Also sets -checkmempool (default: %u)",
                   defaultChainParams->DefaultConsistencyChecks()),
         true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-checkmempool=<n>",
                  strprintf("Run checks every <n> transactions (default: %u)",
                            defaultChainParams->DefaultConsistencyChecks()),
                  true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-checkpoints",
                  strprintf("Only accept block chain matching built-in "
                            "checkpoints (default: %d)",
                            DEFAULT_CHECKPOINTS_ENABLED),
                  true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-deprecatedrpc=<method>",
                  "Allows deprecated RPC method(s) to be used", true,
                  OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-dropmessagestest=<n>",
                  "Randomly drop 1 of every <n> network messages", true,
                  OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-stopafterblockimport",
         strprintf("Stop running after importing blocks from disk (default: %d)",
                   DEFAULT_STOPAFTERBLOCKIMPORT),
         true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-stopatheight",
                  strprintf("Stop running after reaching the given height in "
                            "the main chain (default: %u)",
                            DEFAULT_STOPATHEIGHT),
                  true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-limitancestorcount=<n>",
                  strprintf("Do not accept transactions if number of in-mempool "
                            "ancestors is <n> or more (default: %u)",
                            DEFAULT_ANCESTOR_LIMIT),
                  true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-limitancestorsize=<n>",
         strprintf("Do not accept transactions whose size with all in-mempool "
                   "ancestors exceeds <n> kilobytes (default: %u)",
                   DEFAULT_ANCESTOR_SIZE_LIMIT),
         true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-limitdescendantcount=<n>",
         strprintf("Do not accept transactions if any ancestor would have <n> "
                   "or more in-mempool descendants (default: %u)",
                   DEFAULT_DESCENDANT_LIMIT),
         true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-limitdescendantsize=<n>",
         strprintf("Do not accept transactions if any ancestor would have more "
                   "than <n> kilobytes of in-mempool descendants (default: %u).",
                   DEFAULT_DESCENDANT_SIZE_LIMIT),
         true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-addrmantest", "Allows to test address relay on localhost",
                  true, OptionsCategory::DEBUG_TEST);
 
     gArgs.AddArg("-debug=<category>",
                  strprintf(_("Output debugging information (default: %u, "
                              "supplying <category> is optional)"),
                            0) +
                      ". " +
                      _("If <category> is not supplied or if <category> = 1, "
                        "output all debugging information.") +
                      _("<category> can be:") + " " + ListLogCategories() + ".",
                  false, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-debugexclude=<category>",
         strprintf(_("Exclude debugging information for a category. Can be used "
                     "in conjunction with -debug=1 to output debug logs for all "
                     "categories except one or more specified categories.")),
         false, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-help-debug",
                  _("Show all debugging options (usage: --help -help-debug)"),
                  false, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-logips",
         strprintf(_("Include IP addresses in debug output (default: %d)"),
                   DEFAULT_LOGIPS),
         false, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-logtimestamps",
         strprintf(_("Prepend debug output with timestamp (default: %d)"),
                   DEFAULT_LOGTIMESTAMPS),
         false, OptionsCategory::DEBUG_TEST);
 
     gArgs.AddArg(
         "-logtimemicros",
         strprintf("Add microsecond precision to debug timestamps (default: %d)",
                   DEFAULT_LOGTIMEMICROS),
         true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-mocktime=<n>",
         "Replace actual time with <n> seconds since epoch (default: 0)", true,
         OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-maxsigcachesize=<n>",
         strprintf("Limit size of signature cache to <n> MiB (default: %u)",
                   DEFAULT_MAX_SIG_CACHE_SIZE),
         true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg(
         "-maxscriptcachesize=<n>",
         strprintf("Limit size of script cache to <n> MiB (default: %u)",
                   DEFAULT_MAX_SCRIPT_CACHE_SIZE),
         true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-maxtipage=<n>",
                  strprintf("Maximum tip age in seconds to consider node in "
                            "initial block download (default: %u)",
                            DEFAULT_MAX_TIP_AGE),
                  true, OptionsCategory::DEBUG_TEST);
 
     gArgs.AddArg(
         "-printtoconsole",
         _("Send trace/debug info to console instead of debug.log file"), false,
         OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-printpriority",
                  strprintf("Log transaction priority and fee per kB when "
                            "mining blocks (default: %d)",
                            DEFAULT_PRINTPRIORITY),
                  true, OptionsCategory::DEBUG_TEST);
     gArgs.AddArg("-shrinkdebugfile",
                  _("Shrink debug.log file on client startup (default: 1 when "
                    "no -debug)"),
                  false, OptionsCategory::DEBUG_TEST);
 
     gArgs.AddArg("-uacomment=<cmt>",
                  _("Append comment to the user agent string"), false,
                  OptionsCategory::DEBUG_TEST);
 
     SetupChainParamsBaseOptions();
 
     gArgs.AddArg(
         "-acceptnonstdtxn",
         strprintf(
             "Relay and mine \"non-standard\" transactions (%sdefault: %u)",
             "testnet/regtest only; ", defaultChainParams->RequireStandard()),
         true, OptionsCategory::NODE_RELAY);
     gArgs.AddArg("-excessiveblocksize=<n>",
                  strprintf(_("Do not accept blocks larger than this limit, in "
                              "bytes (default: %d)"),
                            DEFAULT_MAX_BLOCK_SIZE),
                  true, OptionsCategory::NODE_RELAY);
     gArgs.AddArg(
         "-dustrelayfee=<amt>",
         strprintf("Fee rate (in %s/kB) used to defined dust, the value of an "
                   "output such that it will cost about 1/3 of its value in "
                   "fees at this fee rate to spend it. (default: %s)",
                   CURRENCY_UNIT, FormatMoney(DUST_RELAY_TX_FEE)),
         true, OptionsCategory::NODE_RELAY);
     gArgs.AddArg("-limitfreerelay=<n>",
                  strprintf("Continuously rate-limit free transactions to "
                            "<n>*1000 bytes per minute (default: %u)",
                            DEFAULT_LIMITFREERELAY),
                  true, OptionsCategory::NODE_RELAY);
     gArgs.AddArg("-relaypriority",
                  strprintf("Require high priority for relaying free or low-fee "
                            "transactions (default: %d)",
                            DEFAULT_RELAYPRIORITY),
                  true, OptionsCategory::NODE_RELAY);
 
     gArgs.AddArg("-bytespersigop",
                  strprintf(_("Equivalent bytes per sigop in transactions for "
                              "relay and mining (default: %u)"),
                            DEFAULT_BYTES_PER_SIGOP),
                  false, OptionsCategory::NODE_RELAY);
     gArgs.AddArg(
         "-datacarrier",
         strprintf(_("Relay and mine data carrier transactions (default: %d)"),
                   DEFAULT_ACCEPT_DATACARRIER),
         false, OptionsCategory::NODE_RELAY);
     gArgs.AddArg("-datacarriersize",
                  strprintf(_("Maximum size of data in data carrier "
                              "transactions we relay and mine (default: %u)"),
                            MAX_OP_RETURN_RELAY),
                  false, OptionsCategory::NODE_RELAY);
     gArgs.AddArg(
         "-minrelaytxfee=<amt>",
         strprintf(
             _("Fees (in %s/kB) smaller than this are considered zero fee for "
               "relaying, mining and transaction creation (default: %s)"),
             CURRENCY_UNIT, FormatMoney(DEFAULT_MIN_RELAY_TX_FEE_PER_KB)),
         false, OptionsCategory::NODE_RELAY);
     gArgs.AddArg(
         "-whitelistrelay",
         strprintf(_("Accept relayed transactions received from whitelisted "
                     "peers even when not relaying transactions (default: %d)"),
                   DEFAULT_WHITELISTRELAY),
         false, OptionsCategory::NODE_RELAY);
     gArgs.AddArg(
         "-whitelistforcerelay",
         strprintf(_("Force relay of transactions from whitelisted peers even "
                     "if they violate local relay policy (default: %d)"),
                   DEFAULT_WHITELISTFORCERELAY),
         false, OptionsCategory::NODE_RELAY);
 
     // Not sure this really belongs here, but it will do for now.
     // FIXME: This doesn't work anyways.
     gArgs.AddArg("-excessutxocharge=<amt>",
                  strprintf(_("Fees (in %s/kB) to charge per utxo created for "
                              "relaying, and mining (default: %s)"),
                            CURRENCY_UNIT, FormatMoney(DEFAULT_UTXO_FEE)),
                  true, OptionsCategory::NODE_RELAY);
 
     gArgs.AddArg("-blockmaxsize=<n>",
                  strprintf(_("Set maximum block size in bytes (default: %d)"),
                            DEFAULT_MAX_GENERATED_BLOCK_SIZE),
                  false, OptionsCategory::BLOCK_CREATION);
     gArgs.AddArg(
         "-blockprioritypercentage=<n>",
         strprintf(_("Set maximum percentage of a block reserved to "
                     "high-priority/low-fee transactions (default: %d)"),
                   DEFAULT_BLOCK_PRIORITY_PERCENTAGE),
         false, OptionsCategory::BLOCK_CREATION);
     gArgs.AddArg(
         "-blockmintxfee=<amt>",
         strprintf(_("Set lowest fee rate (in %s/kB) for transactions to be "
                     "included in block creation. (default: %s)"),
                   CURRENCY_UNIT, FormatMoney(DEFAULT_BLOCK_MIN_TX_FEE_PER_KB)),
         false, OptionsCategory::BLOCK_CREATION);
 
     gArgs.AddArg("-blockversion=<n>",
                  "Override block version to test forking scenarios", true,
                  OptionsCategory::BLOCK_CREATION);
 
     gArgs.AddArg("-server", _("Accept command line and JSON-RPC commands"),
                  false, OptionsCategory::RPC);
     gArgs.AddArg("-rest",
                  strprintf(_("Accept public REST requests (default: %d)"),
                            DEFAULT_REST_ENABLE),
                  false, OptionsCategory::RPC);
     gArgs.AddArg(
         "-rpcbind=<addr>",
         _("Bind to given address to listen for JSON-RPC connections. Use "
           "[host]:port notation for IPv6. This option can be specified "
           "multiple times (default: bind to all interfaces)"),
         false, OptionsCategory::RPC);
     gArgs.AddArg("-rpccookiefile=<loc>",
                  _("Location of the auth cookie (default: data dir)"), false,
                  OptionsCategory::RPC);
     gArgs.AddArg("-rpcuser=<user>", _("Username for JSON-RPC connections"),
                  false, OptionsCategory::RPC);
     gArgs.AddArg("-rpcpassword=<pw>", _("Password for JSON-RPC connections"),
                  false, OptionsCategory::RPC);
     gArgs.AddArg(
         "-rpcauth=<userpw>",
         _("Username and hashed password for JSON-RPC connections. The field "
           "<userpw> comes in the format: <USERNAME>:<SALT>$<HASH>. A canonical "
           "python script is included in share/rpcuser. The client then "
           "connects normally using the "
           "rpcuser=<USERNAME>/rpcpassword=<PASSWORD> pair of arguments. This "
           "option can be specified multiple times"),
         false, OptionsCategory::RPC);
     gArgs.AddArg(
         "-rpcport=<port>",
         strprintf(_("Listen for JSON-RPC connections on <port> (default: %u or "
                     "testnet: %u)"),
                   defaultBaseParams->RPCPort(), testnetBaseParams->RPCPort()),
         false, OptionsCategory::RPC);
     gArgs.AddArg("-rpcallowip=<ip>",
                  _("Allow JSON-RPC connections from specified source. Valid "
                    "for <ip> are a single IP (e.g. 1.2.3.4), a network/netmask "
                    "(e.g. 1.2.3.4/255.255.255.0) or a network/CIDR (e.g. "
                    "1.2.3.4/24). This option can be specified multiple times"),
                  false, OptionsCategory::RPC);
     gArgs.AddArg(
         "-rpcthreads=<n>",
         strprintf(
             _("Set the number of threads to service RPC calls (default: %d)"),
             DEFAULT_HTTP_THREADS),
         false, OptionsCategory::RPC);
     gArgs.AddArg(
         "-rpccorsdomain=value",
         "Domain from which to accept cross origin requests (browser enforced)",
         false, OptionsCategory::RPC);
 
     gArgs.AddArg("-rpcworkqueue=<n>",
                  strprintf("Set the depth of the work queue to service RPC "
                            "calls (default: %d)",
                            DEFAULT_HTTP_WORKQUEUE),
                  true, OptionsCategory::RPC);
     gArgs.AddArg("-rpcservertimeout=<n>",
                  strprintf("Timeout during HTTP requests (default: %d)",
                            DEFAULT_HTTP_SERVER_TIMEOUT),
                  true, OptionsCategory::RPC);
+
+    // Hidden options
+    gArgs.AddArg("-rpcssl", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-benchmark", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-h", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-help", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-socks", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-tor", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-debugnet", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-whitelistalwaysrelay", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-blockminsize", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-dbcrashratio", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-forcecompactdb", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-usehd", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-parkdeepreorg", "", false, OptionsCategory::HIDDEN);
+    gArgs.AddArg("-replayprotectionactivationtime", "", false,
+                 OptionsCategory::HIDDEN);
+
+    // TODO remove after the Nov 2019 upgrade
+    gArgs.AddArg("-gravitonactivationtime", "", false, OptionsCategory::HIDDEN);
 }
 
 std::string LicenseInfo() {
     const std::string URL_SOURCE_CODE =
         "<https://github.com/Bitcoin-ABC/bitcoin-abc>";
     const std::string URL_WEBSITE = "<https://www.bitcoinabc.org>";
 
     return CopyrightHolders(
                strprintf(_("Copyright (C) %i-%i"), 2009, COPYRIGHT_YEAR) +
                " ") +
            "\n" + "\n" +
            strprintf(_("Please contribute if you find %s useful. "
                        "Visit %s for further information about the software."),
                      PACKAGE_NAME, URL_WEBSITE) +
            "\n" +
            strprintf(_("The source code is available from %s."),
                      URL_SOURCE_CODE) +
            "\n" + "\n" + _("This is experimental software.") + "\n" +
            strprintf(_("Distributed under the MIT software license, see the "
                        "accompanying file %s or %s"),
                      "COPYING", "<https://opensource.org/licenses/MIT>") +
            "\n" + "\n" +
            strprintf(_("This product includes software developed by the "
                        "OpenSSL Project for use in the OpenSSL Toolkit %s and "
                        "cryptographic software written by Eric Young and UPnP "
                        "software written by Thomas Bernard."),
                      "<https://www.openssl.org>") +
            "\n";
 }
 
 static void BlockNotifyCallback(bool initialSync,
                                 const CBlockIndex *pBlockIndex) {
     if (initialSync || !pBlockIndex) {
         return;
     }
 
     std::string strCmd = gArgs.GetArg("-blocknotify", "");
     if (!strCmd.empty()) {
         boost::replace_all(strCmd, "%s", pBlockIndex->GetBlockHash().GetHex());
         std::thread t(runCommand, strCmd);
         // thread runs free
         t.detach();
     }
 }
 
 static bool fHaveGenesis = false;
 static Mutex g_genesis_wait_mutex;
 static std::condition_variable g_genesis_wait_cv;
 
 static void BlockNotifyGenesisWait(bool, const CBlockIndex *pBlockIndex) {
     if (pBlockIndex != nullptr) {
         {
             LOCK(g_genesis_wait_mutex);
             fHaveGenesis = true;
         }
         g_genesis_wait_cv.notify_all();
     }
 }
 
 struct CImportingNow {
     CImportingNow() {
         assert(fImporting == false);
         fImporting = true;
     }
 
     ~CImportingNow() {
         assert(fImporting == true);
         fImporting = false;
     }
 };
 
 // If we're using -prune with -reindex, then delete block files that will be
 // ignored by the reindex.  Since reindexing works by starting at block file 0
 // and looping until a blockfile is missing, do the same here to delete any
 // later block files after a gap. Also delete all rev files since they'll be
 // rewritten by the reindex anyway. This ensures that vinfoBlockFile is in sync
 // with what's actually on disk by the time we start downloading, so that
 // pruning works correctly.
 static void CleanupBlockRevFiles() {
     std::map<std::string, fs::path> mapBlockFiles;
 
     // Glob all blk?????.dat and rev?????.dat files from the blocks directory.
     // Remove the rev files immediately and insert the blk file paths into an
     // ordered map keyed by block file index.
     LogPrintf("Removing unusable blk?????.dat and rev?????.dat files for "
               "-reindex with -prune\n");
     fs::path blocksdir = GetBlocksDir();
     for (fs::directory_iterator it(blocksdir); it != fs::directory_iterator();
          it++) {
         if (fs::is_regular_file(*it) &&
             it->path().filename().string().length() == 12 &&
             it->path().filename().string().substr(8, 4) == ".dat") {
             if (it->path().filename().string().substr(0, 3) == "blk") {
                 mapBlockFiles[it->path().filename().string().substr(3, 5)] =
                     it->path();
             } else if (it->path().filename().string().substr(0, 3) == "rev") {
                 remove(it->path());
             }
         }
     }
 
     // Remove all block files that aren't part of a contiguous set starting at
     // zero by walking the ordered map (keys are block file indices) by keeping
     // a separate counter. Once we hit a gap (or if 0 doesn't exist) start
     // removing block files.
     int nContigCounter = 0;
     for (const std::pair<std::string, fs::path> &item : mapBlockFiles) {
         if (atoi(item.first) == nContigCounter) {
             nContigCounter++;
             continue;
         }
         remove(item.second);
     }
 }
 
 static void ThreadImport(const Config &config,
                          std::vector<fs::path> vImportFiles) {
     RenameThread("bitcoin-loadblk");
 
     {
         CImportingNow imp;
 
         // -reindex
         if (fReindex) {
             int nFile = 0;
             while (true) {
                 CDiskBlockPos pos(nFile, 0);
                 if (!fs::exists(GetBlockPosFilename(pos))) {
                     // No block files left to reindex
                     break;
                 }
                 FILE *file = OpenBlockFile(pos, true);
                 if (!file) {
                     // This error is logged in OpenBlockFile
                     break;
                 }
                 LogPrintf("Reindexing block file blk%05u.dat...\n",
                           (unsigned int)nFile);
                 LoadExternalBlockFile(config, file, &pos);
                 nFile++;
             }
             pblocktree->WriteReindexing(false);
             fReindex = false;
             LogPrintf("Reindexing finished\n");
             // To avoid ending up in a situation without genesis block, re-try
             // initializing (no-op if reindexing worked):
             LoadGenesisBlock(config.GetChainParams());
         }
 
         // hardcoded $DATADIR/bootstrap.dat
         fs::path pathBootstrap = GetDataDir() / "bootstrap.dat";
         if (fs::exists(pathBootstrap)) {
             FILE *file = fsbridge::fopen(pathBootstrap, "rb");
             if (file) {
                 fs::path pathBootstrapOld = GetDataDir() / "bootstrap.dat.old";
                 LogPrintf("Importing bootstrap.dat...\n");
                 LoadExternalBlockFile(config, file);
                 RenameOver(pathBootstrap, pathBootstrapOld);
             } else {
                 LogPrintf("Warning: Could not open bootstrap file %s\n",
                           pathBootstrap.string());
             }
         }
 
         // -loadblock=
         for (const fs::path &path : vImportFiles) {
             FILE *file = fsbridge::fopen(path, "rb");
             if (file) {
                 LogPrintf("Importing blocks file %s...\n", path.string());
                 LoadExternalBlockFile(config, file);
             } else {
                 LogPrintf("Warning: Could not open blocks file %s\n",
                           path.string());
             }
         }
 
         // scan for better chains in the block chain database, that are not yet
         // connected in the active best chain
         CValidationState state;
         if (!ActivateBestChain(config, state)) {
             LogPrintf("Failed to connect best block");
             StartShutdown();
             return;
         }
 
         if (gArgs.GetBoolArg("-stopafterblockimport",
                              DEFAULT_STOPAFTERBLOCKIMPORT)) {
             LogPrintf("Stopping after block import\n");
             StartShutdown();
             return;
         }
     } // End scope of CImportingNow
     if (gArgs.GetArg("-persistmempool", DEFAULT_PERSIST_MEMPOOL)) {
         LoadMempool(config);
     }
     g_is_mempool_loaded = !fRequestShutdown;
 }
 
 /** Sanity checks
  *  Ensure that Bitcoin is running in a usable environment with all
  *  necessary library support.
  */
 static bool InitSanityCheck(void) {
     if (!ECC_InitSanityCheck()) {
         InitError(
             "Elliptic curve cryptography sanity check failure. Aborting.");
         return false;
     }
 
     if (!glibc_sanity_test() || !glibcxx_sanity_test()) {
         return false;
     }
 
     if (!Random_SanityCheck()) {
         InitError("OS cryptographic RNG sanity check failure. Aborting.");
         return false;
     }
 
     return true;
 }
 
 static bool AppInitServers(Config &config,
                            HTTPRPCRequestProcessor &httpRPCRequestProcessor) {
     RPCServerSignals::OnStarted(&OnRPCStarted);
     RPCServerSignals::OnStopped(&OnRPCStopped);
     if (!InitHTTPServer(config)) {
         return false;
     }
     if (!StartRPC()) {
         return false;
     }
     if (!StartHTTPRPC(config, httpRPCRequestProcessor)) {
         return false;
     }
     if (gArgs.GetBoolArg("-rest", DEFAULT_REST_ENABLE) && !StartREST()) {
         return false;
     }
     if (!StartHTTPServer()) {
         return false;
     }
     return true;
 }
 
 // Parameter interaction based on rules
 void InitParameterInteraction() {
     // when specifying an explicit binding address, you want to listen on it
     // even when -connect or -proxy is specified.
     if (gArgs.IsArgSet("-bind")) {
         if (gArgs.SoftSetBoolArg("-listen", true)) {
             LogPrintf(
                 "%s: parameter interaction: -bind set -> setting -listen=1\n",
                 __func__);
         }
     }
     if (gArgs.IsArgSet("-whitebind")) {
         if (gArgs.SoftSetBoolArg("-listen", true)) {
             LogPrintf("%s: parameter interaction: -whitebind set -> setting "
                       "-listen=1\n",
                       __func__);
         }
     }
 
     if (gArgs.IsArgSet("-connect")) {
         // when only connecting to trusted nodes, do not seed via DNS, or listen
         // by default.
         if (gArgs.SoftSetBoolArg("-dnsseed", false)) {
             LogPrintf("%s: parameter interaction: -connect set -> setting "
                       "-dnsseed=0\n",
                       __func__);
         }
         if (gArgs.SoftSetBoolArg("-listen", false)) {
             LogPrintf("%s: parameter interaction: -connect set -> setting "
                       "-listen=0\n",
                       __func__);
         }
     }
 
     if (gArgs.IsArgSet("-proxy")) {
         // to protect privacy, do not listen by default if a default proxy
         // server is specified.
         if (gArgs.SoftSetBoolArg("-listen", false)) {
             LogPrintf(
                 "%s: parameter interaction: -proxy set -> setting -listen=0\n",
                 __func__);
         }
         // to protect privacy, do not use UPNP when a proxy is set. The user may
         // still specify -listen=1 to listen locally, so don't rely on this
         // happening through -listen below.
         if (gArgs.SoftSetBoolArg("-upnp", false)) {
             LogPrintf(
                 "%s: parameter interaction: -proxy set -> setting -upnp=0\n",
                 __func__);
         }
         // to protect privacy, do not discover addresses by default
         if (gArgs.SoftSetBoolArg("-discover", false)) {
             LogPrintf("%s: parameter interaction: -proxy set -> setting "
                       "-discover=0\n",
                       __func__);
         }
     }
 
     if (!gArgs.GetBoolArg("-listen", DEFAULT_LISTEN)) {
         // do not map ports or try to retrieve public IP when not listening
         // (pointless)
         if (gArgs.SoftSetBoolArg("-upnp", false)) {
             LogPrintf(
                 "%s: parameter interaction: -listen=0 -> setting -upnp=0\n",
                 __func__);
         }
         if (gArgs.SoftSetBoolArg("-discover", false)) {
             LogPrintf(
                 "%s: parameter interaction: -listen=0 -> setting -discover=0\n",
                 __func__);
         }
         if (gArgs.SoftSetBoolArg("-listenonion", false)) {
             LogPrintf("%s: parameter interaction: -listen=0 -> setting "
                       "-listenonion=0\n",
                       __func__);
         }
     }
 
     if (gArgs.IsArgSet("-externalip")) {
         // if an explicit public IP is specified, do not try to find others
         if (gArgs.SoftSetBoolArg("-discover", false)) {
             LogPrintf("%s: parameter interaction: -externalip set -> setting "
                       "-discover=0\n",
                       __func__);
         }
     }
 
     // disable whitelistrelay in blocksonly mode
     if (gArgs.GetBoolArg("-blocksonly", DEFAULT_BLOCKSONLY)) {
         if (gArgs.SoftSetBoolArg("-whitelistrelay", false)) {
             LogPrintf("%s: parameter interaction: -blocksonly=1 -> setting "
                       "-whitelistrelay=0\n",
                       __func__);
         }
     }
 
     // Forcing relay from whitelisted hosts implies we will accept relays from
     // them in the first place.
     if (gArgs.GetBoolArg("-whitelistforcerelay", DEFAULT_WHITELISTFORCERELAY)) {
         if (gArgs.SoftSetBoolArg("-whitelistrelay", true)) {
             LogPrintf("%s: parameter interaction: -whitelistforcerelay=1 -> "
                       "setting -whitelistrelay=1\n",
                       __func__);
         }
     }
 
     // Warn if network-specific options (-addnode, -connect, etc) are
     // specified in default section of config file, but not overridden
     // on the command line or in this network's section of the config file.
     gArgs.WarnForSectionOnlyArgs();
 }
 
 static std::string ResolveErrMsg(const char *const optname,
                                  const std::string &strBind) {
     return strprintf(_("Cannot resolve -%s address: '%s'"), optname, strBind);
 }
 
 void InitLogging() {
     BCLog::Logger &logger = GetLogger();
     logger.m_print_to_console = gArgs.GetBoolArg("-printtoconsole", false);
     logger.m_log_timestamps =
         gArgs.GetBoolArg("-logtimestamps", DEFAULT_LOGTIMESTAMPS);
     logger.m_log_time_micros =
         gArgs.GetBoolArg("-logtimemicros", DEFAULT_LOGTIMEMICROS);
 
     fLogIPs = gArgs.GetBoolArg("-logips", DEFAULT_LOGIPS);
 
     LogPrintf("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");
     LogPrintf("%s version %s\n", CLIENT_NAME, FormatFullVersion());
 }
 
 namespace { // Variables internal to initialization process only
 
 int nMaxConnections;
 int nUserMaxConnections;
 int nFD;
 ServiceFlags nLocalServices = ServiceFlags(NODE_NETWORK | NODE_NETWORK_LIMITED);
 } // namespace
 
 [[noreturn]] static void new_handler_terminate() {
     // Rather than throwing std::bad-alloc if allocation fails, terminate
     // immediately to (try to) avoid chain corruption. Since LogPrintf may
     // itself allocate memory, set the handler directly to terminate first.
     std::set_new_handler(std::terminate);
     LogPrintf("Error: Out of memory. Terminating.\n");
 
     // The log was successful, terminate now.
     std::terminate();
 };
 
 bool AppInitBasicSetup() {
 // Step 1: setup
 #ifdef _MSC_VER
     // Turn off Microsoft heap dump noise
     _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE);
     _CrtSetReportFile(_CRT_WARN, CreateFileA("NUL", GENERIC_WRITE, 0, nullptr,
                                              OPEN_EXISTING, 0, 0));
 #endif
 #if _MSC_VER >= 1400
     // Disable confusing "helpful" text message on abort, Ctrl-C
     _set_abort_behavior(0, _WRITE_ABORT_MSG | _CALL_REPORTFAULT);
 #endif
 #ifdef WIN32
 // Enable Data Execution Prevention (DEP)
 // Minimum supported OS versions: WinXP SP3, WinVista >= SP1, Win Server 2008
 // A failure is non-critical and needs no further attention!
 #ifndef PROCESS_DEP_ENABLE
 // We define this here, because GCCs winbase.h limits this to _WIN32_WINNT >=
 // 0x0601 (Windows 7), which is not correct. Can be removed, when GCCs winbase.h
 // is fixed!
 #define PROCESS_DEP_ENABLE 0x00000001
 #endif
     typedef BOOL(WINAPI * PSETPROCDEPPOL)(DWORD);
     PSETPROCDEPPOL setProcDEPPol = (PSETPROCDEPPOL)GetProcAddress(
         GetModuleHandleA("Kernel32.dll"), "SetProcessDEPPolicy");
     if (setProcDEPPol != nullptr) {
         setProcDEPPol(PROCESS_DEP_ENABLE);
     }
 #endif
 
     if (!SetupNetworking()) {
         return InitError("Initializing networking failed");
     }
 
 #ifndef WIN32
     if (!gArgs.GetBoolArg("-sysperms", false)) {
         umask(077);
     }
 
     // Clean shutdown on SIGTERM
     registerSignalHandler(SIGTERM, HandleSIGTERM);
     registerSignalHandler(SIGINT, HandleSIGTERM);
 
     // Reopen debug.log on SIGHUP
     registerSignalHandler(SIGHUP, HandleSIGHUP);
 
     // Ignore SIGPIPE, otherwise it will bring the daemon down if the client
     // closes unexpectedly
     signal(SIGPIPE, SIG_IGN);
 #endif
 
     std::set_new_handler(new_handler_terminate);
 
     return true;
 }
 
 bool AppInitParameterInteraction(Config &config) {
     const CChainParams &chainparams = config.GetChainParams();
     // Step 2: parameter interactions
 
     // also see: InitParameterInteraction()
 
     if (!fs::is_directory(GetBlocksDir())) {
         return InitError(
             strprintf(_("Specified blocks directory \"%s\" does not exist.\n"),
                       gArgs.GetArg("-blocksdir", "").c_str()));
     }
 
     // if using block pruning, then disallow txindex
     if (gArgs.GetArg("-prune", 0)) {
         if (gArgs.GetBoolArg("-txindex", DEFAULT_TXINDEX)) {
             return InitError(_("Prune mode is incompatible with -txindex."));
         }
     }
 
     // if space reserved for high priority transactions is misconfigured
     // stop program execution and warn the user with a proper error message
     const int64_t blkprio = gArgs.GetArg("-blockprioritypercentage",
                                          DEFAULT_BLOCK_PRIORITY_PERCENTAGE);
     if (!config.SetBlockPriorityPercentage(blkprio)) {
         return InitError(_("Block priority percentage has to belong to the "
                            "[0..100] interval."));
     }
 
     // -bind and -whitebind can't be set when not listening
     size_t nUserBind =
         gArgs.GetArgs("-bind").size() + gArgs.GetArgs("-whitebind").size();
     if (nUserBind != 0 && !gArgs.GetBoolArg("-listen", DEFAULT_LISTEN)) {
         return InitError(
             "Cannot set -bind or -whitebind together with -listen=0");
     }
 
     // Make sure enough file descriptors are available
     int nBind = std::max(nUserBind, size_t(1));
     nUserMaxConnections =
         gArgs.GetArg("-maxconnections", DEFAULT_MAX_PEER_CONNECTIONS);
     nMaxConnections = std::max(nUserMaxConnections, 0);
 
     // Trim requested connection counts, to fit into system limitations
     nMaxConnections =
         std::max(std::min(nMaxConnections,
                           (int)(FD_SETSIZE - nBind - MIN_CORE_FILEDESCRIPTORS -
                                 MAX_ADDNODE_CONNECTIONS)),
                  0);
     nFD = RaiseFileDescriptorLimit(nMaxConnections + MIN_CORE_FILEDESCRIPTORS +
                                    MAX_ADDNODE_CONNECTIONS);
     if (nFD < MIN_CORE_FILEDESCRIPTORS) {
         return InitError(_("Not enough file descriptors available."));
     }
     nMaxConnections =
         std::min(nFD - MIN_CORE_FILEDESCRIPTORS - MAX_ADDNODE_CONNECTIONS,
                  nMaxConnections);
 
     if (nMaxConnections < nUserMaxConnections) {
         InitWarning(strprintf(_("Reducing -maxconnections from %d to %d, "
                                 "because of system limitations."),
                               nUserMaxConnections, nMaxConnections));
     }
 
     // Step 3: parameter-to-internal-flags
     if (gArgs.IsArgSet("-debug")) {
         // Special-case: if -debug=0/-nodebug is set, turn off debugging
         // messages
         const std::vector<std::string> &categories = gArgs.GetArgs("-debug");
         if (find(categories.begin(), categories.end(), std::string("0")) ==
             categories.end()) {
             for (const auto &cat : categories) {
                 BCLog::LogFlags flag = BCLog::NONE;
                 if (!GetLogCategory(flag, cat)) {
                     InitWarning(
                         strprintf(_("Unsupported logging category %s=%s."),
                                   "-debug", cat));
                     continue;
                 }
                 GetLogger().EnableCategory(flag);
             }
         }
     }
 
     // Now remove the logging categories which were explicitly excluded
     for (const std::string &cat : gArgs.GetArgs("-debugexclude")) {
         BCLog::LogFlags flag = BCLog::NONE;
         if (!GetLogCategory(flag, cat)) {
             InitWarning(strprintf(_("Unsupported logging category %s=%s."),
                                   "-debugexclude", cat));
             continue;
         }
         GetLogger().DisableCategory(flag);
     }
 
     // Check for -debugnet
     if (gArgs.GetBoolArg("-debugnet", false)) {
         InitWarning(
             _("Unsupported argument -debugnet ignored, use -debug=net."));
     }
     // Check for -socks - as this is a privacy risk to continue, exit here
     if (gArgs.IsArgSet("-socks")) {
         return InitError(
             _("Unsupported argument -socks found. Setting SOCKS version isn't "
               "possible anymore, only SOCKS5 proxies are supported."));
     }
     // Check for -tor - as this is a privacy risk to continue, exit here
     if (gArgs.GetBoolArg("-tor", false)) {
         return InitError(_("Unsupported argument -tor found, use -onion."));
     }
 
     if (gArgs.GetBoolArg("-benchmark", false)) {
         InitWarning(
             _("Unsupported argument -benchmark ignored, use -debug=bench."));
     }
 
     if (gArgs.GetBoolArg("-whitelistalwaysrelay", false)) {
         InitWarning(_("Unsupported argument -whitelistalwaysrelay ignored, use "
                       "-whitelistrelay and/or -whitelistforcerelay."));
     }
 
     if (gArgs.IsArgSet("-blockminsize")) {
         InitWarning("Unsupported argument -blockminsize ignored.");
     }
 
     // Checkmempool and checkblockindex default to true in regtest mode
     int ratio = std::min<int>(
         std::max<int>(
             gArgs.GetArg("-checkmempool",
                          chainparams.DefaultConsistencyChecks() ? 1 : 0),
             0),
         1000000);
     if (ratio != 0) {
         g_mempool.setSanityCheck(1.0 / ratio);
     }
     fCheckBlockIndex = gArgs.GetBoolArg("-checkblockindex",
                                         chainparams.DefaultConsistencyChecks());
     fCheckpointsEnabled =
         gArgs.GetBoolArg("-checkpoints", DEFAULT_CHECKPOINTS_ENABLED);
     if (fCheckpointsEnabled) {
         LogPrintf("Checkpoints will be verified.\n");
     } else {
         LogPrintf("Skipping checkpoint verification.\n");
     }
 
     hashAssumeValid = uint256S(
         gArgs.GetArg("-assumevalid",
                      chainparams.GetConsensus().defaultAssumeValid.GetHex()));
     if (!hashAssumeValid.IsNull()) {
         LogPrintf("Assuming ancestors of block %s have valid signatures.\n",
                   hashAssumeValid.GetHex());
     } else {
         LogPrintf("Validating signatures for all blocks.\n");
     }
 
     if (gArgs.IsArgSet("-minimumchainwork")) {
         const std::string minChainWorkStr =
             gArgs.GetArg("-minimumchainwork", "");
         if (!IsHexNumber(minChainWorkStr)) {
             return InitError(strprintf(
                 "Invalid non-hex (%s) minimum chain work value specified",
                 minChainWorkStr));
         }
         nMinimumChainWork = UintToArith256(uint256S(minChainWorkStr));
     } else {
         nMinimumChainWork =
             UintToArith256(chainparams.GetConsensus().nMinimumChainWork);
     }
     LogPrintf("Setting nMinimumChainWork=%s\n", nMinimumChainWork.GetHex());
     if (nMinimumChainWork <
         UintToArith256(chainparams.GetConsensus().nMinimumChainWork)) {
         LogPrintf("Warning: nMinimumChainWork set below default value of %s\n",
                   chainparams.GetConsensus().nMinimumChainWork.GetHex());
     }
 
     // mempool limits
     int64_t nMempoolSizeMax =
         gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000;
     int64_t nMempoolSizeMin =
         gArgs.GetArg("-limitdescendantsize", DEFAULT_DESCENDANT_SIZE_LIMIT) *
         1000 * 40;
     if (nMempoolSizeMax < 0 || nMempoolSizeMax < nMempoolSizeMin) {
         return InitError(strprintf(_("-maxmempool must be at least %d MB"),
                                    std::ceil(nMempoolSizeMin / 1000000.0)));
     }
 
     // -par=0 means autodetect, but nScriptCheckThreads==0 means no concurrency
     nScriptCheckThreads = gArgs.GetArg("-par", DEFAULT_SCRIPTCHECK_THREADS);
     if (nScriptCheckThreads <= 0) {
         nScriptCheckThreads += GetNumCores();
     }
     if (nScriptCheckThreads <= 1) {
         nScriptCheckThreads = 0;
     } else if (nScriptCheckThreads > MAX_SCRIPTCHECK_THREADS) {
         nScriptCheckThreads = MAX_SCRIPTCHECK_THREADS;
     }
 
     // Configure excessive block size.
     const uint64_t nProposedExcessiveBlockSize =
         gArgs.GetArg("-excessiveblocksize", DEFAULT_MAX_BLOCK_SIZE);
     if (!config.SetMaxBlockSize(nProposedExcessiveBlockSize)) {
         return InitError(
             _("Excessive block size must be > 1,000,000 bytes (1MB)"));
     }
 
     // Check blockmaxsize does not exceed maximum accepted block size.
     const uint64_t nProposedMaxGeneratedBlockSize =
         gArgs.GetArg("-blockmaxsize", DEFAULT_MAX_GENERATED_BLOCK_SIZE);
     if (nProposedMaxGeneratedBlockSize > config.GetMaxBlockSize()) {
         auto msg = _("Max generated block size (blockmaxsize) cannot exceed "
                      "the excessive block size (excessiveblocksize)");
         return InitError(msg);
     }
 
     // block pruning; get the amount of disk space (in MiB) to allot for block &
     // undo files
     int64_t nPruneArg = gArgs.GetArg("-prune", 0);
     if (nPruneArg < 0) {
         return InitError(
             _("Prune cannot be configured with a negative value."));
     }
     nPruneTarget = (uint64_t)nPruneArg * 1024 * 1024;
     if (nPruneArg == 1) {
         // manual pruning: -prune=1
         LogPrintf("Block pruning enabled.  Use RPC call "
                   "pruneblockchain(height) to manually prune block and undo "
                   "files.\n");
         nPruneTarget = std::numeric_limits<uint64_t>::max();
         fPruneMode = true;
     } else if (nPruneTarget) {
         if (nPruneTarget < MIN_DISK_SPACE_FOR_BLOCK_FILES) {
             return InitError(
                 strprintf(_("Prune configured below the minimum of %d MiB.  "
                             "Please use a higher number."),
                           MIN_DISK_SPACE_FOR_BLOCK_FILES / 1024 / 1024));
         }
         LogPrintf("Prune configured to target %uMiB on disk for block and undo "
                   "files.\n",
                   nPruneTarget / 1024 / 1024);
         fPruneMode = true;
     }
 
     nConnectTimeout = gArgs.GetArg("-timeout", DEFAULT_CONNECT_TIMEOUT);
     if (nConnectTimeout <= 0) {
         nConnectTimeout = DEFAULT_CONNECT_TIMEOUT;
     }
 
     // Obtain the amount to charge excess UTXO
     if (gArgs.IsArgSet("-excessutxocharge")) {
         Amount n = Amount::zero();
         auto parsed = ParseMoney(gArgs.GetArg("-excessutxocharge", ""), n);
         if (!parsed || Amount::zero() > n) {
             return InitError(AmountErrMsg(
                 "excessutxocharge", gArgs.GetArg("-excessutxocharge", "")));
         }
         config.SetExcessUTXOCharge(n);
     } else {
         config.SetExcessUTXOCharge(DEFAULT_UTXO_FEE);
     }
 
     if (gArgs.IsArgSet("-minrelaytxfee")) {
         Amount n = Amount::zero();
         auto parsed = ParseMoney(gArgs.GetArg("-minrelaytxfee", ""), n);
         if (!parsed || n == Amount::zero()) {
             return InitError(AmountErrMsg("minrelaytxfee",
                                           gArgs.GetArg("-minrelaytxfee", "")));
         }
         // High fee check is done afterward in WalletParameterInteraction()
         ::minRelayTxFee = CFeeRate(n);
     }
 
     // Sanity check argument for min fee for including tx in block
     // TODO: Harmonize which arguments need sanity checking and where that
     // happens.
     if (gArgs.IsArgSet("-blockmintxfee")) {
         Amount n = Amount::zero();
         if (!ParseMoney(gArgs.GetArg("-blockmintxfee", ""), n)) {
             return InitError(AmountErrMsg("blockmintxfee",
                                           gArgs.GetArg("-blockmintxfee", "")));
         }
     }
 
     // Feerate used to define dust.  Shouldn't be changed lightly as old
     // implementations may inadvertently create non-standard transactions.
     if (gArgs.IsArgSet("-dustrelayfee")) {
         Amount n = Amount::zero();
         auto parsed = ParseMoney(gArgs.GetArg("-dustrelayfee", ""), n);
         if (!parsed || Amount::zero() == n) {
             return InitError(AmountErrMsg("dustrelayfee",
                                           gArgs.GetArg("-dustrelayfee", "")));
         }
         dustRelayFee = CFeeRate(n);
     }
 
     fRequireStandard =
         !gArgs.GetBoolArg("-acceptnonstdtxn", !chainparams.RequireStandard());
     if (chainparams.RequireStandard() && !fRequireStandard) {
         return InitError(
             strprintf("acceptnonstdtxn is not currently supported for %s chain",
                       chainparams.NetworkIDString()));
     }
     nBytesPerSigOp = gArgs.GetArg("-bytespersigop", nBytesPerSigOp);
 
     if (!g_wallet_init_interface.ParameterInteraction()) {
         return false;
     }
 
     fIsBareMultisigStd =
         gArgs.GetBoolArg("-permitbaremultisig", DEFAULT_PERMIT_BAREMULTISIG);
     fAcceptDatacarrier =
         gArgs.GetBoolArg("-datacarrier", DEFAULT_ACCEPT_DATACARRIER);
 
     // Option to startup with mocktime set (used for regression testing):
     SetMockTime(gArgs.GetArg("-mocktime", 0)); // SetMockTime(0) is a no-op
 
     if (gArgs.GetBoolArg("-peerbloomfilters", DEFAULT_PEERBLOOMFILTERS)) {
         nLocalServices = ServiceFlags(nLocalServices | NODE_BLOOM);
     }
 
     // Signal Bitcoin Cash support.
     // TODO: remove some time after the hardfork when no longer needed
     // to differentiate the network nodes.
     nLocalServices = ServiceFlags(nLocalServices | NODE_BITCOIN_CASH);
 
     nMaxTipAge = gArgs.GetArg("-maxtipage", DEFAULT_MAX_TIP_AGE);
 
     return true;
 }
 
 static bool LockDataDirectory(bool probeOnly) {
     // Make sure only a single Bitcoin process is using the data directory.
     fs::path datadir = GetDataDir();
     if (!DirIsWritable(datadir)) {
         return InitError(strprintf(
             _("Cannot write to data directory '%s'; check permissions."),
             datadir.string()));
     }
     if (!LockDirectory(datadir, ".lock", probeOnly)) {
         return InitError(strprintf(_("Cannot obtain a lock on data directory "
                                      "%s. %s is probably already running."),
                                    datadir.string(), _(PACKAGE_NAME)));
     }
     return true;
 }
 
 bool AppInitSanityChecks() {
     // Step 4: sanity checks
 
     // Initialize elliptic curve code
     std::string sha256_algo = SHA256AutoDetect();
     LogPrintf("Using the '%s' SHA256 implementation\n", sha256_algo);
     RandomInit();
     ECC_Start();
     globalVerifyHandle.reset(new ECCVerifyHandle());
 
     // Sanity check
     if (!InitSanityCheck()) {
         return InitError(strprintf(
             _("Initialization sanity check failed. %s is shutting down."),
             _(PACKAGE_NAME)));
     }
 
     // Probe the data directory lock to give an early error message, if possible
     // We cannot hold the data directory lock here, as the forking for daemon()
     // hasn't yet happened, and a fork will cause weird behavior to it.
     return LockDataDirectory(true);
 }
 
 bool AppInitLockDataDirectory() {
     // After daemonization get the data directory lock again and hold on to it
     // until exit. This creates a slight window for a race condition to happen,
     // however this condition is harmless: it will at most make us exit without
     // printing a message to console.
     if (!LockDataDirectory(false)) {
         // Detailed error printed inside LockDataDirectory
         return false;
     }
     return true;
 }
 
 bool AppInitMain(Config &config, RPCServer &rpcServer,
                  HTTPRPCRequestProcessor &httpRPCRequestProcessor) {
     // Step 4a: application initialization
     const CChainParams &chainparams = config.GetChainParams();
 
 #ifndef WIN32
     CreatePidFile(GetPidFile(), getpid());
 #endif
 
     BCLog::Logger &logger = GetLogger();
 
     bool default_shrinkdebugfile = logger.DefaultShrinkDebugFile();
     if (gArgs.GetBoolArg("-shrinkdebugfile", default_shrinkdebugfile)) {
         // Do this first since it both loads a bunch of debug.log into memory,
         // and because this needs to happen before any other debug.log printing.
         logger.ShrinkDebugFile();
     }
 
     if (logger.m_print_to_file) {
         if (!logger.OpenDebugLog()) {
             return InitError(strprintf("Could not open debug log file %s",
                                        logger.GetDebugLogPath().string()));
         }
     }
 
     if (!logger.m_log_timestamps) {
         LogPrintf("Startup time: %s\n", FormatISO8601DateTime(GetTime()));
     }
     LogPrintf("Default data directory %s\n", GetDefaultDataDir().string());
     LogPrintf("Using data directory %s\n", GetDataDir().string());
     LogPrintf(
         "Using config file %s\n",
         GetConfigFile(gArgs.GetArg("-conf", BITCOIN_CONF_FILENAME)).string());
     LogPrintf("Using at most %i automatic connections (%i file descriptors "
               "available)\n",
               nMaxConnections, nFD);
 
     // Warn about relative -datadir path.
     if (gArgs.IsArgSet("-datadir") &&
         !fs::path(gArgs.GetArg("-datadir", "")).is_absolute()) {
         LogPrintf("Warning: relative datadir option '%s' specified, which will "
                   "be interpreted relative to the current working directory "
                   "'%s'. This is fragile, because if bitcoin is started in the "
                   "future from a different location, it will be unable to "
                   "locate the current data files. There could also be data "
                   "loss if bitcoin is started while in a temporary "
                   "directory.\n",
                   gArgs.GetArg("-datadir", ""), fs::current_path().string());
     }
 
     InitSignatureCache();
     InitScriptExecutionCache();
 
     LogPrintf("Using %u threads for script verification\n",
               nScriptCheckThreads);
     if (nScriptCheckThreads) {
         for (int i = 0; i < nScriptCheckThreads - 1; i++) {
             threadGroup.create_thread(&ThreadScriptCheck);
         }
     }
 
     // Start the lightweight task scheduler thread
     CScheduler::Function serviceLoop =
         boost::bind(&CScheduler::serviceQueue, &scheduler);
     threadGroup.create_thread(boost::bind(&TraceThread<CScheduler::Function>,
                                           "scheduler", serviceLoop));
 
     GetMainSignals().RegisterBackgroundSignalScheduler(scheduler);
     GetMainSignals().RegisterWithMempoolSignals(g_mempool);
 
     /**
      * Register RPC commands regardless of -server setting so they will be
      * available in the GUI RPC console even if external calls are disabled.
      */
     RegisterAllRPCCommands(config, rpcServer, tableRPC);
     g_wallet_init_interface.RegisterRPC(tableRPC);
 
     /**
      * Start the RPC server.  It will be started in "warmup" mode and not
      * process calls yet (but it will verify that the server is there and will
      * be ready later).  Warmup mode will be completed when initialisation is
      * finished.
      */
     if (gArgs.GetBoolArg("-server", false)) {
         uiInterface.InitMessage.connect(SetRPCWarmupStatus);
         if (!AppInitServers(config, httpRPCRequestProcessor)) {
             return InitError(
                 _("Unable to start HTTP server. See debug log for details."));
         }
     }
 
     // Step 5: verify wallet database integrity
     if (!g_wallet_init_interface.Verify(chainparams)) {
         return false;
     }
 
     // Step 6: network initialization
 
     // Note that we absolutely cannot open any actual connections
     // until the very end ("start node") as the UTXO/block state
     // is not yet setup and may end up being set up twice if we
     // need to reindex later.
 
     assert(!g_connman);
     g_connman = std::unique_ptr<CConnman>(
         new CConnman(config, GetRand(std::numeric_limits<uint64_t>::max()),
                      GetRand(std::numeric_limits<uint64_t>::max())));
     CConnman &connman = *g_connman;
 
     peerLogic.reset(new PeerLogicValidation(&connman, scheduler));
     RegisterValidationInterface(peerLogic.get());
 
     // sanitize comments per BIP-0014, format user agent and check total size
     std::vector<std::string> uacomments;
     for (const std::string &cmt : gArgs.GetArgs("-uacomment")) {
         if (cmt != SanitizeString(cmt, SAFE_CHARS_UA_COMMENT))
             return InitError(strprintf(
                 _("User Agent comment (%s) contains unsafe characters."), cmt));
         uacomments.push_back(cmt);
     }
     const std::string strSubVersion =
         FormatSubVersion(CLIENT_NAME, CLIENT_VERSION, uacomments);
     if (strSubVersion.size() > MAX_SUBVERSION_LENGTH) {
         return InitError(strprintf(
             _("Total length of network version string (%i) exceeds maximum "
               "length (%i). Reduce the number or size of uacomments."),
             strSubVersion.size(), MAX_SUBVERSION_LENGTH));
     }
 
     if (gArgs.IsArgSet("-onlynet")) {
         std::set<enum Network> nets;
         for (const std::string &snet : gArgs.GetArgs("-onlynet")) {
             enum Network net = ParseNetwork(snet);
             if (net == NET_UNROUTABLE) {
                 return InitError(strprintf(
                     _("Unknown network specified in -onlynet: '%s'"), snet));
             }
             nets.insert(net);
         }
         for (int n = 0; n < NET_MAX; n++) {
             enum Network net = (enum Network)n;
             if (!nets.count(net)) SetLimited(net);
         }
     }
 
     // Check for host lookup allowed before parsing any network related
     // parameters
     fNameLookup = gArgs.GetBoolArg("-dns", DEFAULT_NAME_LOOKUP);
 
     bool proxyRandomize =
         gArgs.GetBoolArg("-proxyrandomize", DEFAULT_PROXYRANDOMIZE);
     // -proxy sets a proxy for all outgoing network traffic
     // -noproxy (or -proxy=0) as well as the empty string can be used to not set
     // a proxy, this is the default
     std::string proxyArg = gArgs.GetArg("-proxy", "");
     SetLimited(NET_ONION);
     if (proxyArg != "" && proxyArg != "0") {
         CService proxyAddr;
         if (!Lookup(proxyArg.c_str(), proxyAddr, 9050, fNameLookup)) {
             return InitError(strprintf(
                 _("Invalid -proxy address or hostname: '%s'"), proxyArg));
         }
 
         proxyType addrProxy = proxyType(proxyAddr, proxyRandomize);
         if (!addrProxy.IsValid()) {
             return InitError(strprintf(
                 _("Invalid -proxy address or hostname: '%s'"), proxyArg));
         }
 
         SetProxy(NET_IPV4, addrProxy);
         SetProxy(NET_IPV6, addrProxy);
         SetProxy(NET_ONION, addrProxy);
         SetNameProxy(addrProxy);
         // by default, -proxy sets onion as reachable, unless -noonion later
         SetLimited(NET_ONION, false);
     }
 
     // -onion can be used to set only a proxy for .onion, or override normal
     // proxy for .onion addresses.
     // -noonion (or -onion=0) disables connecting to .onion entirely. An empty
     // string is used to not override the onion proxy (in which case it defaults
     // to -proxy set above, or none)
     std::string onionArg = gArgs.GetArg("-onion", "");
     if (onionArg != "") {
         if (onionArg == "0") {     // Handle -noonion/-onion=0
             SetLimited(NET_ONION); // set onions as unreachable
         } else {
             CService onionProxy;
             if (!Lookup(onionArg.c_str(), onionProxy, 9050, fNameLookup)) {
                 return InitError(strprintf(
                     _("Invalid -onion address or hostname: '%s'"), onionArg));
             }
             proxyType addrOnion = proxyType(onionProxy, proxyRandomize);
             if (!addrOnion.IsValid()) {
                 return InitError(strprintf(
                     _("Invalid -onion address or hostname: '%s'"), onionArg));
             }
             SetProxy(NET_ONION, addrOnion);
             SetLimited(NET_ONION, false);
         }
     }
 
     // see Step 2: parameter interactions for more information about these
     fListen = gArgs.GetBoolArg("-listen", DEFAULT_LISTEN);
     fDiscover = gArgs.GetBoolArg("-discover", true);
     fRelayTxes = !gArgs.GetBoolArg("-blocksonly", DEFAULT_BLOCKSONLY);
 
     for (const std::string &strAddr : gArgs.GetArgs("-externalip")) {
         CService addrLocal;
         if (Lookup(strAddr.c_str(), addrLocal, GetListenPort(), fNameLookup) &&
             addrLocal.IsValid()) {
             AddLocal(addrLocal, LOCAL_MANUAL);
         } else {
             return InitError(ResolveErrMsg("externalip", strAddr));
         }
     }
 
 #if ENABLE_ZMQ
     pzmqNotificationInterface = CZMQNotificationInterface::Create();
 
     if (pzmqNotificationInterface) {
         RegisterValidationInterface(pzmqNotificationInterface);
     }
 #endif
     // unlimited unless -maxuploadtarget is set
     uint64_t nMaxOutboundLimit = 0;
     uint64_t nMaxOutboundTimeframe = MAX_UPLOAD_TIMEFRAME;
 
     if (gArgs.IsArgSet("-maxuploadtarget")) {
         nMaxOutboundLimit =
             gArgs.GetArg("-maxuploadtarget", DEFAULT_MAX_UPLOAD_TARGET) * 1024 *
             1024;
     }
 
     // Step 7: load block chain
 
     fReindex = gArgs.GetBoolArg("-reindex", false);
     bool fReindexChainState = gArgs.GetBoolArg("-reindex-chainstate", false);
 
     // cache size calculations
     int64_t nTotalCache = (gArgs.GetArg("-dbcache", nDefaultDbCache) << 20);
     // total cache cannot be less than nMinDbCache
     nTotalCache = std::max(nTotalCache, nMinDbCache << 20);
     // total cache cannot be greater than nMaxDbcache
     nTotalCache = std::min(nTotalCache, nMaxDbCache << 20);
     int64_t nBlockTreeDBCache =
         std::min(nTotalCache / 8, nMaxBlockDBCache << 20);
     nTotalCache -= nBlockTreeDBCache;
     int64_t nTxIndexCache =
         std::min(nTotalCache / 8, gArgs.GetBoolArg("-txindex", DEFAULT_TXINDEX)
                                       ? nMaxTxIndexCache << 20
                                       : 0);
     nTotalCache -= nTxIndexCache;
     // use 25%-50% of the remainder for disk cache
     int64_t nCoinDBCache =
         std::min(nTotalCache / 2, (nTotalCache / 4) + (1 << 23));
     // cap total coins db cache
     nCoinDBCache = std::min(nCoinDBCache, nMaxCoinsDBCache << 20);
     nTotalCache -= nCoinDBCache;
     // the rest goes to in-memory cache
     nCoinCacheUsage = nTotalCache;
     int64_t nMempoolSizeMax =
         gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000;
     LogPrintf("Cache configuration:\n");
     LogPrintf("* Using %.1fMiB for block index database\n",
               nBlockTreeDBCache * (1.0 / 1024 / 1024));
     if (gArgs.GetBoolArg("-txindex", DEFAULT_TXINDEX)) {
         LogPrintf("* Using %.1fMiB for transaction index database\n",
                   nTxIndexCache * (1.0 / 1024 / 1024));
     }
     LogPrintf("* Using %.1fMiB for chain state database\n",
               nCoinDBCache * (1.0 / 1024 / 1024));
     LogPrintf("* Using %.1fMiB for in-memory UTXO set (plus up to %.1fMiB of "
               "unused mempool space)\n",
               nCoinCacheUsage * (1.0 / 1024 / 1024),
               nMempoolSizeMax * (1.0 / 1024 / 1024));
 
     int64_t nStart = 0;
     bool fLoaded = false;
     while (!fLoaded && !fRequestShutdown) {
         bool fReset = fReindex;
         std::string strLoadError;
 
         uiInterface.InitMessage(_("Loading block index..."));
 
         LOCK(cs_main);
 
         nStart = GetTimeMillis();
         do {
             try {
                 UnloadBlockIndex();
                 pcoinsTip.reset();
                 pcoinsdbview.reset();
                 pcoinscatcher.reset();
                 pblocktree.reset(
                     new CBlockTreeDB(nBlockTreeDBCache, false, fReset));
 
                 if (fReset) {
                     pblocktree->WriteReindexing(true);
                     // If we're reindexing in prune mode, wipe away unusable
                     // block files and all undo data files
                     if (fPruneMode) {
                         CleanupBlockRevFiles();
                     }
                 }
 
                 if (fRequestShutdown) {
                     break;
                 }
 
                 // LoadBlockIndex will load fHavePruned if we've ever removed a
                 // block file from disk.
                 // Note that it also sets fReindex based on the disk flag!
                 // From here on out fReindex and fReset mean something
                 // different!
                 if (!LoadBlockIndex(config)) {
                     strLoadError = _("Error loading block database");
                     break;
                 }
 
                 // If the loaded chain has a wrong genesis, bail out immediately
                 // (we're likely using a testnet datadir, or the other way
                 // around).
                 if (!mapBlockIndex.empty() &&
                     !LookupBlockIndex(
                         chainparams.GetConsensus().hashGenesisBlock)) {
                     return InitError(_("Incorrect or no genesis block found. "
                                        "Wrong datadir for network?"));
                 }
 
                 // Check for changed -prune state.  What we are concerned about
                 // is a user who has pruned blocks in the past, but is now
                 // trying to run unpruned.
                 if (fHavePruned && !fPruneMode) {
                     strLoadError =
                         _("You need to rebuild the database using -reindex to "
                           "go back to unpruned mode.  This will redownload the "
                           "entire blockchain");
                     break;
                 }
 
                 // At this point blocktree args are consistent with what's on
                 // disk. If we're not mid-reindex (based on disk + args), add a
                 // genesis block on disk (otherwise we use the one already on
                 // disk).
                 // This is called again in ThreadImport after the reindex
                 // completes.
                 if (!fReindex && !LoadGenesisBlock(chainparams)) {
                     strLoadError = _("Error initializing block database");
                     break;
                 }
 
                 // At this point we're either in reindex or we've loaded a
                 // useful block tree into mapBlockIndex!
 
                 pcoinsdbview.reset(new CCoinsViewDB(
                     nCoinDBCache, false, fReset || fReindexChainState));
                 pcoinscatcher.reset(
                     new CCoinsViewErrorCatcher(pcoinsdbview.get()));
 
                 // If necessary, upgrade from older database format.
                 // This is a no-op if we cleared the coinsviewdb with -reindex
                 // or -reindex-chainstate
                 if (!pcoinsdbview->Upgrade()) {
                     strLoadError = _("Error upgrading chainstate database");
                     break;
                 }
 
                 // ReplayBlocks is a no-op if we cleared the coinsviewdb with
                 // -reindex or -reindex-chainstate
                 if (!ReplayBlocks(config, pcoinsdbview.get())) {
                     strLoadError =
                         _("Unable to replay blocks. You will need to rebuild "
                           "the database using -reindex-chainstate.");
                     break;
                 }
 
                 // The on-disk coinsdb is now in a good state, create the cache
                 pcoinsTip.reset(new CCoinsViewCache(pcoinscatcher.get()));
 
                 bool is_coinsview_empty = fReset || fReindexChainState ||
                                           pcoinsTip->GetBestBlock().IsNull();
                 if (!is_coinsview_empty) {
                     // LoadChainTip sets chainActive based on pcoinsTip's best
                     // block
                     if (!LoadChainTip(config)) {
                         strLoadError = _("Error initializing block database");
                         break;
                     }
                     assert(chainActive.Tip() != nullptr);
                 }
 
                 if (!fReset) {
                     // Note that RewindBlockIndex MUST run even if we're about
                     // to -reindex-chainstate. It both disconnects blocks based
                     // on chainActive, and drops block data in mapBlockIndex
                     // based on lack of available witness data.
                     uiInterface.InitMessage(_("Rewinding blocks..."));
                     if (!RewindBlockIndex(config)) {
                         strLoadError = _("Unable to rewind the database to a "
                                          "pre-fork state. You will need to "
                                          "redownload the blockchain");
                         break;
                     }
                 }
 
                 if (!is_coinsview_empty) {
                     uiInterface.InitMessage(_("Verifying blocks..."));
                     if (fHavePruned &&
                         gArgs.GetArg("-checkblocks", DEFAULT_CHECKBLOCKS) >
                             MIN_BLOCKS_TO_KEEP) {
                         LogPrintf(
                             "Prune: pruned datadir may not have more than %d "
                             "blocks; only checking available blocks\n",
                             MIN_BLOCKS_TO_KEEP);
                     }
 
                     CBlockIndex *tip = chainActive.Tip();
                     RPCNotifyBlockChange(true, tip);
                     if (tip && tip->nTime >
                                    GetAdjustedTime() + MAX_FUTURE_BLOCK_TIME) {
                         strLoadError = _(
                             "The block database contains a block which appears "
                             "to be from the future. This may be due to your "
                             "computer's date and time being set incorrectly. "
                             "Only rebuild the block database if you are sure "
                             "that your computer's date and time are correct");
                         break;
                     }
 
                     if (!CVerifyDB().VerifyDB(
                             config, pcoinsdbview.get(),
                             gArgs.GetArg("-checklevel", DEFAULT_CHECKLEVEL),
                             gArgs.GetArg("-checkblocks",
                                          DEFAULT_CHECKBLOCKS))) {
                         strLoadError = _("Corrupted block database detected");
                         break;
                     }
                 }
             } catch (const std::exception &e) {
                 LogPrintf("%s\n", e.what());
                 strLoadError = _("Error opening block database");
                 break;
             }
 
             fLoaded = true;
         } while (false);
 
         if (!fLoaded && !fRequestShutdown) {
             // first suggest a reindex
             if (!fReset) {
                 bool fRet = uiInterface.ThreadSafeQuestion(
                     strLoadError + ".\n\n" +
                         _("Do you want to rebuild the block database now?"),
                     strLoadError + ".\nPlease restart with -reindex or "
                                    "-reindex-chainstate to recover.",
                     "",
                     CClientUIInterface::MSG_ERROR |
                         CClientUIInterface::BTN_ABORT);
                 if (fRet) {
                     fReindex = true;
                     fRequestShutdown = false;
                 } else {
                     LogPrintf("Aborted block database rebuild. Exiting.\n");
                     return false;
                 }
             } else {
                 return InitError(strLoadError);
             }
         }
     }
 
     // As LoadBlockIndex can take several minutes, it's possible the user
     // requested to kill the GUI during the last operation. If so, exit.
     // As the program has not fully started yet, Shutdown() is possibly
     // overkill.
     if (fRequestShutdown) {
         LogPrintf("Shutdown requested. Exiting.\n");
         return false;
     }
     if (fLoaded) {
         LogPrintf(" block index %15dms\n", GetTimeMillis() - nStart);
     }
 
     // Encoded addresses using cashaddr instead of base58.
     // We do this by default to avoid confusion with BTC addresses.
     config.SetCashAddrEncoding(gArgs.GetBoolArg("-usecashaddr", true));
 
     // Step 8: load indexers
     if (gArgs.GetBoolArg("-txindex", DEFAULT_TXINDEX)) {
         g_txindex = std::make_unique<TxIndex>(nTxIndexCache, false, fReindex);
         g_txindex->Start();
     }
 
     // Step 9: load wallet
     if (!g_wallet_init_interface.Open(chainparams)) {
         return false;
     }
 
     // Step 10: data directory maintenance
 
     // if pruning, unset the service bit and perform the initial blockstore
     // prune after any wallet rescanning has taken place.
     if (fPruneMode) {
         LogPrintf("Unsetting NODE_NETWORK on prune mode\n");
         nLocalServices = ServiceFlags(nLocalServices & ~NODE_NETWORK);
         if (!fReindex) {
             uiInterface.InitMessage(_("Pruning blockstore..."));
             PruneAndFlush();
         }
     }
 
     // Step 11: import blocks
     if (!CheckDiskSpace(GetDataDir())) {
         InitError(
             strprintf(_("Error: Disk space is low for %s"), GetDataDir()));
         return false;
     }
     if (!CheckDiskSpace(GetBlocksDir())) {
         InitError(
             strprintf(_("Error: Disk space is low for %s"), GetBlocksDir()));
         return false;
     }
 
     // Either install a handler to notify us when genesis activates, or set
     // fHaveGenesis directly.
     // No locking, as this happens before any background thread is started.
     if (chainActive.Tip() == nullptr) {
         uiInterface.NotifyBlockTip.connect(BlockNotifyGenesisWait);
     } else {
         fHaveGenesis = true;
     }
 
     if (gArgs.IsArgSet("-blocknotify")) {
         uiInterface.NotifyBlockTip.connect(BlockNotifyCallback);
     }
 
     std::vector<fs::path> vImportFiles;
     for (const std::string &strFile : gArgs.GetArgs("-loadblock")) {
         vImportFiles.push_back(strFile);
     }
 
     threadGroup.create_thread(
         boost::bind(&ThreadImport, std::ref(config), vImportFiles));
 
     // Wait for genesis block to be processed
     {
         WAIT_LOCK(g_genesis_wait_mutex, lock);
         // We previously could hang here if StartShutdown() is called prior to
         // ThreadImport getting started, so instead we just wait on a timer to
         // check ShutdownRequested() regularly.
         while (!fHaveGenesis && !ShutdownRequested()) {
             g_genesis_wait_cv.wait_for(lock, std::chrono::milliseconds(500));
         }
         uiInterface.NotifyBlockTip.disconnect(BlockNotifyGenesisWait);
     }
 
     if (ShutdownRequested()) {
         return false;
     }
 
     // Step 12: start node
 
     int chain_active_height;
 
     //// debug print
     {
         LOCK(cs_main);
         LogPrintf("mapBlockIndex.size() = %u\n", mapBlockIndex.size());
         chain_active_height = chainActive.Height();
     }
     LogPrintf("nBestHeight = %d\n", chain_active_height);
 
     if (gArgs.GetBoolArg("-listenonion", DEFAULT_LISTEN_ONION)) {
         StartTorControl();
     }
 
     Discover();
 
     // Map ports with UPnP
     if (gArgs.GetBoolArg("-upnp", DEFAULT_UPNP)) {
         StartMapPort();
     }
 
     CConnman::Options connOptions;
     connOptions.nLocalServices = nLocalServices;
     connOptions.nMaxConnections = nMaxConnections;
     connOptions.nMaxOutbound =
         std::min(MAX_OUTBOUND_CONNECTIONS, connOptions.nMaxConnections);
     connOptions.nMaxAddnode = MAX_ADDNODE_CONNECTIONS;
     connOptions.nMaxFeeler = 1;
     connOptions.nBestHeight = chain_active_height;
     connOptions.uiInterface = &uiInterface;
     connOptions.m_msgproc = peerLogic.get();
     connOptions.nSendBufferMaxSize =
         1000 * gArgs.GetArg("-maxsendbuffer", DEFAULT_MAXSENDBUFFER);
     connOptions.nReceiveFloodSize =
         1000 * gArgs.GetArg("-maxreceivebuffer", DEFAULT_MAXRECEIVEBUFFER);
     connOptions.m_added_nodes = gArgs.GetArgs("-addnode");
 
     connOptions.nMaxOutboundTimeframe = nMaxOutboundTimeframe;
     connOptions.nMaxOutboundLimit = nMaxOutboundLimit;
 
     for (const std::string &strBind : gArgs.GetArgs("-bind")) {
         CService addrBind;
         if (!Lookup(strBind.c_str(), addrBind, GetListenPort(), false)) {
             return InitError(ResolveErrMsg("bind", strBind));
         }
         connOptions.vBinds.push_back(addrBind);
     }
 
     for (const std::string &strBind : gArgs.GetArgs("-whitebind")) {
         CService addrBind;
         if (!Lookup(strBind.c_str(), addrBind, 0, false)) {
             return InitError(ResolveErrMsg("whitebind", strBind));
         }
         if (addrBind.GetPort() == 0) {
             return InitError(strprintf(
                 _("Need to specify a port with -whitebind: '%s'"), strBind));
         }
         connOptions.vWhiteBinds.push_back(addrBind);
     }
 
     for (const auto &net : gArgs.GetArgs("-whitelist")) {
         CSubNet subnet;
         LookupSubNet(net.c_str(), subnet);
         if (!subnet.IsValid()) {
             return InitError(strprintf(
                 _("Invalid netmask specified in -whitelist: '%s'"), net));
         }
         connOptions.vWhitelistedRange.push_back(subnet);
     }
 
     connOptions.vSeedNodes = gArgs.GetArgs("-seednode");
 
     // Initiate outbound connections unless connect=0
     connOptions.m_use_addrman_outgoing = !gArgs.IsArgSet("-connect");
     if (!connOptions.m_use_addrman_outgoing) {
         const auto connect = gArgs.GetArgs("-connect");
         if (connect.size() != 1 || connect[0] != "0") {
             connOptions.m_specified_outgoing = connect;
         }
     }
     if (!connman.Start(scheduler, connOptions)) {
         return false;
     }
 
     // Step 13: finished
 
     SetRPCWarmupFinished();
     uiInterface.InitMessage(_("Done loading"));
 
     g_wallet_init_interface.Start(scheduler);
 
     return true;
 }
diff --git a/src/interfaces/node.cpp b/src/interfaces/node.cpp
index 4efcb35a0..9be84db33 100644
--- a/src/interfaces/node.cpp
+++ b/src/interfaces/node.cpp
@@ -1,306 +1,309 @@
 // Copyright (c) 2018 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <interfaces/node.h>
 
 #include <addrdb.h>
 #include <amount.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <config.h>
 #include <init.h>
 #include <interfaces/handler.h>
 #include <interfaces/wallet.h>
 #include <net.h>
 #include <net_processing.h>
 #include <netaddress.h>
 #include <netbase.h>
 #include <policy/fees.h>
 #include <policy/policy.h>
 #include <primitives/block.h>
 #include <rpc/server.h>
 #include <scheduler.h>
 #include <sync.h>
 #include <txmempool.h>
 #include <ui_interface.h>
 #include <util.h>
 #include <validation.h>
 #include <warnings.h>
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 #ifdef ENABLE_WALLET
 #include <wallet/fees.h>
 #include <wallet/wallet.h>
 #define CHECK_WALLET(x) x
 #else
 #define CHECK_WALLET(x)                                                        \
     throw std::logic_error("Wallet function called in non-wallet build.")
 #endif
 
 #include <boost/thread/thread.hpp>
 #include <univalue.h>
 
 #include <atomic>
 
 class HTTPRPCRequestProcessor;
 
 namespace interfaces {
 namespace {
 
     class NodeImpl : public Node {
-        void parseParameters(int argc, const char *const argv[]) override {
-            gArgs.ParseParameters(argc, argv);
+        bool parseParameters(int argc, const char *const argv[],
+                             std::string &error) override {
+            return gArgs.ParseParameters(argc, argv, error);
+        }
+        bool readConfigFiles(std::string &error) override {
+            return gArgs.ReadConfigFiles(error);
         }
-        void readConfigFiles() override { gArgs.ReadConfigFiles(); }
         bool softSetArg(const std::string &arg,
                         const std::string &value) override {
             return gArgs.SoftSetArg(arg, value);
         }
         bool softSetBoolArg(const std::string &arg, bool value) override {
             return gArgs.SoftSetBoolArg(arg, value);
         }
         void selectParams(const std::string &network) override {
             SelectParams(network);
         }
         std::string getNetwork() override { return Params().NetworkIDString(); }
         void initLogging() override { InitLogging(); }
         void initParameterInteraction() override { InitParameterInteraction(); }
         std::string getWarnings(const std::string &type) override {
             return GetWarnings(type);
         }
         bool baseInitialize(Config &config) override {
             return AppInitBasicSetup() && AppInitParameterInteraction(config) &&
                    AppInitSanityChecks() && AppInitLockDataDirectory();
         }
         bool
         appInitMain(Config &config, RPCServer &rpcServer,
                     HTTPRPCRequestProcessor &httpRPCRequestProcessor) override {
             return AppInitMain(config, rpcServer, httpRPCRequestProcessor);
         }
         void appShutdown() override {
             Interrupt();
             Shutdown();
         }
         void startShutdown() override { StartShutdown(); }
         bool shutdownRequested() override { return ShutdownRequested(); }
         void mapPort(bool use_upnp) override {
             if (use_upnp) {
                 StartMapPort();
             } else {
                 InterruptMapPort();
                 StopMapPort();
             }
         }
         void setupServerArgs() override { return SetupServerArgs(); }
         bool getProxy(Network net, proxyType &proxy_info) override {
             return GetProxy(net, proxy_info);
         }
         size_t getNodeCount(CConnman::NumConnections flags) override {
             return g_connman ? g_connman->GetNodeCount(flags) : 0;
         }
         bool getNodesStats(NodesStats &stats) override {
             stats.clear();
 
             if (g_connman) {
                 std::vector<CNodeStats> stats_temp;
                 g_connman->GetNodeStats(stats_temp);
 
                 stats.reserve(stats_temp.size());
                 for (auto &node_stats_temp : stats_temp) {
                     stats.emplace_back(std::move(node_stats_temp), false,
                                        CNodeStateStats());
                 }
 
                 // Try to retrieve the CNodeStateStats for each node.
                 TRY_LOCK(::cs_main, lockMain);
                 if (lockMain) {
                     for (auto &node_stats : stats) {
                         std::get<1>(node_stats) =
                             GetNodeStateStats(std::get<0>(node_stats).nodeid,
                                               std::get<2>(node_stats));
                     }
                 }
                 return true;
             }
             return false;
         }
         bool getBanned(banmap_t &banmap) override {
             if (g_connman) {
                 g_connman->GetBanned(banmap);
                 return true;
             }
             return false;
         }
         bool ban(const CNetAddr &net_addr, BanReason reason,
                  int64_t ban_time_offset) override {
             if (g_connman) {
                 g_connman->Ban(net_addr, reason, ban_time_offset);
                 return true;
             }
             return false;
         }
         bool unban(const CSubNet &ip) override {
             if (g_connman) {
                 g_connman->Unban(ip);
                 return true;
             }
             return false;
         }
         bool disconnect(NodeId id) override {
             if (g_connman) {
                 return g_connman->DisconnectNode(id);
             }
             return false;
         }
         int64_t getTotalBytesRecv() override {
             return g_connman ? g_connman->GetTotalBytesRecv() : 0;
         }
         int64_t getTotalBytesSent() override {
             return g_connman ? g_connman->GetTotalBytesSent() : 0;
         }
         size_t getMempoolSize() override { return g_mempool.size(); }
         size_t getMempoolDynamicUsage() override {
             return g_mempool.DynamicMemoryUsage();
         }
         bool getHeaderTip(int &height, int64_t &block_time) override {
             LOCK(::cs_main);
             if (::pindexBestHeader) {
                 height = ::pindexBestHeader->nHeight;
                 block_time = ::pindexBestHeader->GetBlockTime();
                 return true;
             }
             return false;
         }
         int getNumBlocks() override {
             LOCK(::cs_main);
             return ::chainActive.Height();
         }
         int64_t getLastBlockTime() override {
             LOCK(::cs_main);
             if (::chainActive.Tip()) {
                 return ::chainActive.Tip()->GetBlockTime();
             }
             // Genesis block's time of current network
             return Params().GenesisBlock().GetBlockTime();
         }
         double getVerificationProgress() override {
             const CBlockIndex *tip;
             {
                 LOCK(::cs_main);
                 tip = ::chainActive.Tip();
             }
             return GuessVerificationProgress(Params().TxData(), tip);
         }
         bool isInitialBlockDownload() override {
             return IsInitialBlockDownload();
         }
         bool getReindex() override { return ::fReindex; }
         bool getImporting() override { return ::fImporting; }
         void setNetworkActive(bool active) override {
             if (g_connman) {
                 g_connman->SetNetworkActive(active);
             }
         }
         bool getNetworkActive() override {
             return g_connman && g_connman->GetNetworkActive();
         }
         Amount getMaxTxFee() override { return ::maxTxFee; }
         CFeeRate estimateSmartFee() override { return g_mempool.estimateFee(); }
         CFeeRate getDustRelayFee() override { return ::dustRelayFee; }
         UniValue executeRpc(Config &config, const std::string &command,
                             const UniValue &params,
                             const std::string &uri) override {
             JSONRPCRequest req;
             req.params = params;
             req.strMethod = command;
             req.URI = uri;
             return ::tableRPC.execute(config, req);
         }
         std::vector<std::string> listRpcCommands() override {
             return ::tableRPC.listCommands();
         }
         void rpcSetTimerInterfaceIfUnset(RPCTimerInterface *iface) override {
             RPCSetTimerInterfaceIfUnset(iface);
         }
         void rpcUnsetTimerInterface(RPCTimerInterface *iface) override {
             RPCUnsetTimerInterface(iface);
         }
         bool getUnspentOutput(const COutPoint &output, Coin &coin) override {
             LOCK(::cs_main);
             return ::pcoinsTip->GetCoin(output, coin);
         }
         std::vector<std::unique_ptr<Wallet>> getWallets() override {
 #ifdef ENABLE_WALLET
             std::vector<std::unique_ptr<Wallet>> wallets;
             for (CWallet *wallet : GetWallets()) {
                 wallets.emplace_back(MakeWallet(*wallet));
             }
             return wallets;
 #else
             throw std::logic_error(
                 "Node::getWallets() called in non-wallet build.");
 #endif
         }
         std::unique_ptr<Handler> handleInitMessage(InitMessageFn fn) override {
             return MakeHandler(::uiInterface.InitMessage.connect(fn));
         }
         std::unique_ptr<Handler> handleMessageBox(MessageBoxFn fn) override {
             return MakeHandler(::uiInterface.ThreadSafeMessageBox.connect(fn));
         }
         std::unique_ptr<Handler> handleQuestion(QuestionFn fn) override {
             return MakeHandler(::uiInterface.ThreadSafeQuestion.connect(fn));
         }
         std::unique_ptr<Handler>
         handleShowProgress(ShowProgressFn fn) override {
             return MakeHandler(::uiInterface.ShowProgress.connect(fn));
         }
         std::unique_ptr<Handler> handleLoadWallet(LoadWalletFn fn) override {
             CHECK_WALLET(return MakeHandler(::uiInterface.LoadWallet.connect(
                 [fn](CWallet *wallet) { fn(MakeWallet(*wallet)); })));
         }
         std::unique_ptr<Handler> handleNotifyNumConnectionsChanged(
             NotifyNumConnectionsChangedFn fn) override {
             return MakeHandler(
                 ::uiInterface.NotifyNumConnectionsChanged.connect(fn));
         }
         std::unique_ptr<Handler> handleNotifyNetworkActiveChanged(
             NotifyNetworkActiveChangedFn fn) override {
             return MakeHandler(
                 ::uiInterface.NotifyNetworkActiveChanged.connect(fn));
         }
         std::unique_ptr<Handler>
         handleNotifyAlertChanged(NotifyAlertChangedFn fn) override {
             return MakeHandler(::uiInterface.NotifyAlertChanged.connect(fn));
         }
         std::unique_ptr<Handler>
         handleBannedListChanged(BannedListChangedFn fn) override {
             return MakeHandler(::uiInterface.BannedListChanged.connect(fn));
         }
         std::unique_ptr<Handler>
         handleNotifyBlockTip(NotifyBlockTipFn fn) override {
             return MakeHandler(::uiInterface.NotifyBlockTip.connect(
                 [fn](bool initial_download, const CBlockIndex *block) {
                     fn(initial_download, block->nHeight, block->GetBlockTime(),
                        GuessVerificationProgress(Params().TxData(), block));
                 }));
         }
         std::unique_ptr<Handler>
         handleNotifyHeaderTip(NotifyHeaderTipFn fn) override {
             return MakeHandler(::uiInterface.NotifyHeaderTip.connect(
                 [fn](bool initial_download, const CBlockIndex *block) {
                     fn(initial_download, block->nHeight, block->GetBlockTime(),
                        GuessVerificationProgress(Params().TxData(), block));
                 }));
         }
     };
 
 } // namespace
 
 std::unique_ptr<Node> MakeNode() {
     return std::make_unique<NodeImpl>();
 }
 
 } // namespace interfaces
diff --git a/src/interfaces/node.h b/src/interfaces/node.h
index a9d55aa0e..98c3cc8d3 100644
--- a/src/interfaces/node.h
+++ b/src/interfaces/node.h
@@ -1,252 +1,253 @@
 // Copyright (c) 2018 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_INTERFACES_NODE_H
 #define BITCOIN_INTERFACES_NODE_H
 
 #include <addrdb.h>     // For banmap_t
 #include <amount.h>     // For Amount
 #include <net.h>        // For CConnman::NumConnections
 #include <netaddress.h> // For Network
 
 #include <cstddef>
 #include <cstdint>
 #include <functional>
 #include <memory>
 #include <string>
 #include <tuple>
 #include <vector>
 
 class CCoinControl;
 class CFeeRate;
 struct CNodeStateStats;
 struct CNodeStats;
 class Coin;
 class Config;
 class HTTPRPCRequestProcessor;
 class proxyType;
 class RPCServer;
 class RPCTimerInterface;
 class UniValue;
 
 namespace interfaces {
 class Handler;
 class Wallet;
 
 //! Top-level interface for a bitcoin node (bitcoind process).
 class Node {
 public:
     virtual ~Node() {}
 
     //! Set command line arguments.
-    virtual void parseParameters(int argc, const char *const argv[]) = 0;
+    virtual bool parseParameters(int argc, const char *const argv[],
+                                 std::string &error) = 0;
 
     //! Set a command line argument if it doesn't already have a value
     virtual bool softSetArg(const std::string &arg,
                             const std::string &value) = 0;
 
     //! Set a command line boolean argument if it doesn't already have a value
     virtual bool softSetBoolArg(const std::string &arg, bool value) = 0;
 
     //! Load settings from configuration file.
-    virtual void readConfigFiles() = 0;
+    virtual bool readConfigFiles(std::string &error) = 0;
 
     //! Choose network parameters.
     virtual void selectParams(const std::string &network) = 0;
 
     //! Get network name.
     virtual std::string getNetwork() = 0;
 
     //! Init logging.
     virtual void initLogging() = 0;
 
     //! Init parameter interaction.
     virtual void initParameterInteraction() = 0;
 
     //! Get warnings.
     virtual std::string getWarnings(const std::string &type) = 0;
 
     //! Initialize app dependencies.
     virtual bool baseInitialize(Config &config) = 0;
 
     //! Start node.
     virtual bool
     appInitMain(Config &config, RPCServer &rpcServer,
                 HTTPRPCRequestProcessor &httpRPCRequestProcessor) = 0;
 
     //! Stop node.
     virtual void appShutdown() = 0;
 
     //! Start shutdown.
     virtual void startShutdown() = 0;
 
     //! Return whether shutdown was requested.
     virtual bool shutdownRequested() = 0;
 
     //! Setup arguments
     virtual void setupServerArgs() = 0;
 
     //! Map port.
     virtual void mapPort(bool use_upnp) = 0;
 
     //! Get proxy.
     virtual bool getProxy(Network net, proxyType &proxy_info) = 0;
 
     //! Get number of connections.
     virtual size_t getNodeCount(CConnman::NumConnections flags) = 0;
 
     //! Get stats for connected nodes.
     using NodesStats =
         std::vector<std::tuple<CNodeStats, bool, CNodeStateStats>>;
     virtual bool getNodesStats(NodesStats &stats) = 0;
 
     //! Get ban map entries.
     virtual bool getBanned(banmap_t &banmap) = 0;
 
     //! Ban node.
     virtual bool ban(const CNetAddr &net_addr, BanReason reason,
                      int64_t ban_time_offset) = 0;
 
     //! Unban node.
     virtual bool unban(const CSubNet &ip) = 0;
 
     //! Disconnect node.
     virtual bool disconnect(NodeId id) = 0;
 
     //! Get total bytes recv.
     virtual int64_t getTotalBytesRecv() = 0;
 
     //! Get total bytes sent.
     virtual int64_t getTotalBytesSent() = 0;
 
     //! Get mempool size.
     virtual size_t getMempoolSize() = 0;
 
     //! Get mempool dynamic usage.
     virtual size_t getMempoolDynamicUsage() = 0;
 
     //! Get header tip height and time.
     virtual bool getHeaderTip(int &height, int64_t &block_time) = 0;
 
     //! Get num blocks.
     virtual int getNumBlocks() = 0;
 
     //! Get last block time.
     virtual int64_t getLastBlockTime() = 0;
 
     //! Get verification progress.
     virtual double getVerificationProgress() = 0;
 
     //! Is initial block download.
     virtual bool isInitialBlockDownload() = 0;
 
     //! Get reindex.
     virtual bool getReindex() = 0;
 
     //! Get importing.
     virtual bool getImporting() = 0;
 
     //! Set network active.
     virtual void setNetworkActive(bool active) = 0;
 
     //! Get network active.
     virtual bool getNetworkActive() = 0;
 
     //! Get max tx fee.
     virtual Amount getMaxTxFee() = 0;
 
     //! Estimate smart fee.
     virtual CFeeRate estimateSmartFee() = 0;
 
     //! Get dust relay fee.
     virtual CFeeRate getDustRelayFee() = 0;
 
     //! Execute rpc command.
     virtual UniValue executeRpc(Config &config, const std::string &command,
                                 const UniValue &params,
                                 const std::string &uri) = 0;
 
     //! List rpc commands.
     virtual std::vector<std::string> listRpcCommands() = 0;
 
     //! Set RPC timer interface if unset.
     virtual void rpcSetTimerInterfaceIfUnset(RPCTimerInterface *iface) = 0;
 
     //! Unset RPC timer interface.
     virtual void rpcUnsetTimerInterface(RPCTimerInterface *iface) = 0;
 
     //! Get unspent outputs associated with a transaction.
     virtual bool getUnspentOutput(const COutPoint &output, Coin &coin) = 0;
 
     //! Return interfaces for accessing wallets (if any).
     virtual std::vector<std::unique_ptr<Wallet>> getWallets() = 0;
 
     //! Register handler for init messages.
     using InitMessageFn = std::function<void(const std::string &message)>;
     virtual std::unique_ptr<Handler> handleInitMessage(InitMessageFn fn) = 0;
 
     //! Register handler for message box messages.
     using MessageBoxFn =
         std::function<bool(const std::string &message,
                            const std::string &caption, unsigned int style)>;
     virtual std::unique_ptr<Handler> handleMessageBox(MessageBoxFn fn) = 0;
 
     //! Register handler for question messages.
     using QuestionFn = std::function<bool(
         const std::string &message, const std::string &non_interactive_message,
         const std::string &caption, unsigned int style)>;
     virtual std::unique_ptr<Handler> handleQuestion(QuestionFn fn) = 0;
 
     //! Register handler for progress messages.
     using ShowProgressFn = std::function<void(
         const std::string &title, int progress, bool resume_possible)>;
     virtual std::unique_ptr<Handler> handleShowProgress(ShowProgressFn fn) = 0;
 
     //! Register handler for load wallet messages.
     using LoadWalletFn = std::function<void(std::unique_ptr<Wallet> wallet)>;
     virtual std::unique_ptr<Handler> handleLoadWallet(LoadWalletFn fn) = 0;
 
     //! Register handler for number of connections changed messages.
     using NotifyNumConnectionsChangedFn =
         std::function<void(int new_num_connections)>;
     virtual std::unique_ptr<Handler>
     handleNotifyNumConnectionsChanged(NotifyNumConnectionsChangedFn fn) = 0;
 
     //! Register handler for network active messages.
     using NotifyNetworkActiveChangedFn =
         std::function<void(bool network_active)>;
     virtual std::unique_ptr<Handler>
     handleNotifyNetworkActiveChanged(NotifyNetworkActiveChangedFn fn) = 0;
 
     //! Register handler for notify alert messages.
     using NotifyAlertChangedFn = std::function<void()>;
     virtual std::unique_ptr<Handler>
     handleNotifyAlertChanged(NotifyAlertChangedFn fn) = 0;
 
     //! Register handler for ban list messages.
     using BannedListChangedFn = std::function<void()>;
     virtual std::unique_ptr<Handler>
     handleBannedListChanged(BannedListChangedFn fn) = 0;
 
     //! Register handler for block tip messages.
     using NotifyBlockTipFn =
         std::function<void(bool initial_download, int height,
                            int64_t block_time, double verification_progress)>;
     virtual std::unique_ptr<Handler>
     handleNotifyBlockTip(NotifyBlockTipFn fn) = 0;
 
     //! Register handler for header tip messages.
     using NotifyHeaderTipFn =
         std::function<void(bool initial_download, int height,
                            int64_t block_time, double verification_progress)>;
     virtual std::unique_ptr<Handler>
     handleNotifyHeaderTip(NotifyHeaderTipFn fn) = 0;
 };
 
 //! Return implementation of Node interface.
 std::unique_ptr<Node> MakeNode();
 
 } // namespace interfaces
 
 #endif // BITCOIN_INTERFACES_NODE_H
diff --git a/src/qt/bitcoin.cpp b/src/qt/bitcoin.cpp
index 239ebf516..c9fcbbaf5 100644
--- a/src/qt/bitcoin.cpp
+++ b/src/qt/bitcoin.cpp
@@ -1,844 +1,858 @@
 // Copyright (c) 2011-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <qt/bitcoingui.h>
 
 #include <chainparams.h>
 #include <config.h>
 #include <fs.h>
 #include <httprpc.h>
 #include <init.h>
 #include <interfaces/handler.h>
 #include <interfaces/node.h>
 #include <qt/clientmodel.h>
 #include <qt/guiconstants.h>
 #include <qt/guiutil.h>
 #include <qt/intro.h>
 #include <qt/networkstyle.h>
 #include <qt/optionsmodel.h>
 #include <qt/platformstyle.h>
 #include <qt/splashscreen.h>
 #include <qt/utilitydialog.h>
 #include <qt/winshutdownmonitor.h>
 #include <rpc/server.h>
 #include <ui_interface.h>
 #include <uint256.h>
 #include <util.h>
 #include <walletinitinterface.h>
 #include <warnings.h>
 
 #ifdef ENABLE_WALLET
 #include <qt/paymentserver.h>
 #include <qt/walletmodel.h>
 #endif
 
 #include <QApplication>
 #include <QDebug>
 #include <QLibraryInfo>
 #include <QLocale>
 #include <QMessageBox>
 #include <QSettings>
 #include <QStringList>
 #include <QThread>
 #include <QTimer>
 #include <QTranslator>
 
 #if defined(QT_STATICPLUGIN)
 #include <QtPlugin>
 #if QT_VERSION < 0x050400
 Q_IMPORT_PLUGIN(AccessibleFactory)
 #endif
 #if defined(QT_QPA_PLATFORM_XCB)
 Q_IMPORT_PLUGIN(QXcbIntegrationPlugin);
 #elif defined(QT_QPA_PLATFORM_WINDOWS)
 Q_IMPORT_PLUGIN(QWindowsIntegrationPlugin);
 #elif defined(QT_QPA_PLATFORM_COCOA)
 Q_IMPORT_PLUGIN(QCocoaIntegrationPlugin);
 #endif
 #endif
 
 #include <cstdint>
 
 // Declare meta types used for QMetaObject::invokeMethod
 Q_DECLARE_METATYPE(bool *)
 Q_DECLARE_METATYPE(Amount)
 Q_DECLARE_METATYPE(uint256)
 
 // Config is non-copyable so we can only register pointers to it
 Q_DECLARE_METATYPE(Config *)
 
 static void InitMessage(const std::string &message) {
     LogPrintf("init message: %s\n", message);
 }
 
 /**
  * Translate string to current locale using Qt.
  */
 static std::string Translate(const char *psz) {
     return QCoreApplication::translate("bitcoin-abc", psz).toStdString();
 }
 
 static QString GetLangTerritory() {
     QSettings settings;
     // Get desired locale (e.g. "de_DE")
     // 1) System default language
     QString lang_territory = QLocale::system().name();
     // 2) Language from QSettings
     QString lang_territory_qsettings =
         settings.value("language", "").toString();
     if (!lang_territory_qsettings.isEmpty()) {
         lang_territory = lang_territory_qsettings;
     }
     // 3) -lang command line argument
     lang_territory = QString::fromStdString(
         gArgs.GetArg("-lang", lang_territory.toStdString()));
     return lang_territory;
 }
 
 /** Set up translations */
 static void initTranslations(QTranslator &qtTranslatorBase,
                              QTranslator &qtTranslator,
                              QTranslator &translatorBase,
                              QTranslator &translator) {
     // Remove old translators
     QApplication::removeTranslator(&qtTranslatorBase);
     QApplication::removeTranslator(&qtTranslator);
     QApplication::removeTranslator(&translatorBase);
     QApplication::removeTranslator(&translator);
 
     // Get desired locale (e.g. "de_DE")
     // 1) System default language
     QString lang_territory = GetLangTerritory();
 
     // Convert to "de" only by truncating "_DE"
     QString lang = lang_territory;
     lang.truncate(lang_territory.lastIndexOf('_'));
 
     // Load language files for configured locale:
     // - First load the translator for the base language, without territory
     // - Then load the more specific locale translator
 
     // Load e.g. qt_de.qm
     if (qtTranslatorBase.load(
             "qt_" + lang,
             QLibraryInfo::location(QLibraryInfo::TranslationsPath))) {
         QApplication::installTranslator(&qtTranslatorBase);
     }
 
     // Load e.g. qt_de_DE.qm
     if (qtTranslator.load(
             "qt_" + lang_territory,
             QLibraryInfo::location(QLibraryInfo::TranslationsPath))) {
         QApplication::installTranslator(&qtTranslator);
     }
 
     // Load e.g. bitcoin_de.qm (shortcut "de" needs to be defined in
     // bitcoin.qrc)
     if (translatorBase.load(lang, ":/translations/")) {
         QApplication::installTranslator(&translatorBase);
     }
 
     // Load e.g. bitcoin_de_DE.qm (shortcut "de_DE" needs to be defined in
     // bitcoin.qrc)
     if (translator.load(lang_territory, ":/translations/")) {
         QApplication::installTranslator(&translator);
     }
 }
 
 /* qDebug() message handler --> debug.log */
 void DebugMessageHandler(QtMsgType type, const QMessageLogContext &context,
                          const QString &msg) {
     Q_UNUSED(context);
     if (type == QtDebugMsg) {
         LogPrint(BCLog::QT, "GUI: %s\n", msg.toStdString());
     } else {
         LogPrintf("GUI: %s\n", msg.toStdString());
     }
 }
 
 /**
  * Class encapsulating Bitcoin ABC startup and shutdown.
  * Allows running startup and shutdown in a different thread from the UI thread.
  */
 class BitcoinABC : public QObject {
     Q_OBJECT
 public:
     explicit BitcoinABC(interfaces::Node &node);
 
 public Q_SLOTS:
     void initialize(Config *config, RPCServer *rpcServer,
                     HTTPRPCRequestProcessor *httpRPCRequestProcessor);
     void shutdown();
 
 Q_SIGNALS:
     void initializeResult(bool success);
     void shutdownResult();
     void runawayException(const QString &message);
 
 private:
     /// Pass fatal exception message to UI thread
     void handleRunawayException(const std::exception *e);
 
     interfaces::Node &m_node;
 };
 
 /** Main Bitcoin application object */
 class BitcoinApplication : public QApplication {
     Q_OBJECT
 public:
     explicit BitcoinApplication(interfaces::Node &node, int &argc, char **argv);
     ~BitcoinApplication();
 
 #ifdef ENABLE_WALLET
     /// Create payment server
     void createPaymentServer();
 #endif
     /// parameter interaction/setup based on rules
     void parameterSetup();
     /// Create options model
     void createOptionsModel(bool resetSettings);
     /// Create main window
     void createWindow(const Config *, const NetworkStyle *networkStyle);
     /// Create splash screen
     void createSplashScreen(const NetworkStyle *networkStyle);
 
     /// Request core initialization
     void requestInitialize(Config &config, RPCServer &rpcServer,
                            HTTPRPCRequestProcessor &httpRPCRequestProcessor);
     /// Request core shutdown
     void requestShutdown(Config &config);
 
     /// Get process return value
     int getReturnValue() const { return returnValue; }
 
     /// Get window identifier of QMainWindow (BitcoinGUI)
     WId getMainWinId() const;
 
+    /// Setup platform style
+    void setupPlatformStyle();
+
 public Q_SLOTS:
     void initializeResult(bool success);
     void shutdownResult();
     /// Handle runaway exceptions. Shows a message box with the problem and
     /// quits the program.
     void handleRunawayException(const QString &message);
 
 Q_SIGNALS:
     void requestedInitialize(Config *config, RPCServer *rpcServer,
                              HTTPRPCRequestProcessor *httpRPCRequestProcessor);
     void requestedShutdown();
     void stopThread();
     void splashFinished(QWidget *window);
 
 private:
     QThread *coreThread;
     interfaces::Node &m_node;
     OptionsModel *optionsModel;
     ClientModel *clientModel;
     BitcoinGUI *window;
     QTimer *pollShutdownTimer;
 #ifdef ENABLE_WALLET
     PaymentServer *paymentServer;
     std::vector<WalletModel *> m_wallet_models;
 #endif
     int returnValue;
     const PlatformStyle *platformStyle;
     std::unique_ptr<QWidget> shutdownWindow;
 
     void startThread();
 };
 
 #include <qt/bitcoin.moc>
 
 BitcoinABC::BitcoinABC(interfaces::Node &node) : QObject(), m_node(node) {}
 
 void BitcoinABC::handleRunawayException(const std::exception *e) {
     PrintExceptionContinue(e, "Runaway exception");
     Q_EMIT runawayException(QString::fromStdString(m_node.getWarnings("gui")));
 }
 
 void BitcoinABC::initialize(Config *config, RPCServer *rpcServer,
                             HTTPRPCRequestProcessor *httpRPCRequestProcessor) {
     try {
         qDebug() << __func__ << ": Running initialization in thread";
         bool rv =
             m_node.appInitMain(*config, *rpcServer, *httpRPCRequestProcessor);
         Q_EMIT initializeResult(rv);
     } catch (const std::exception &e) {
         handleRunawayException(&e);
     } catch (...) {
         handleRunawayException(nullptr);
     }
 }
 
 void BitcoinABC::shutdown() {
     try {
         qDebug() << __func__ << ": Running Shutdown in thread";
         m_node.appShutdown();
         qDebug() << __func__ << ": Shutdown finished";
         Q_EMIT shutdownResult();
     } catch (const std::exception &e) {
         handleRunawayException(&e);
     } catch (...) {
         handleRunawayException(nullptr);
     }
 }
 
 BitcoinApplication::BitcoinApplication(interfaces::Node &node, int &argc,
                                        char **argv)
     : QApplication(argc, argv), coreThread(0), m_node(node), optionsModel(0),
       clientModel(0), window(0), pollShutdownTimer(0),
 #ifdef ENABLE_WALLET
       paymentServer(0), m_wallet_models(),
 #endif
-      returnValue(0) {
+      returnValue(0), platformStyle(0) {
     setQuitOnLastWindowClosed(false);
+}
 
-    // UI per-platform customization.
+void BitcoinApplication::setupPlatformStyle() {
+    // UI per-platform customization
     // This must be done inside the BitcoinApplication constructor, or after it,
     // because PlatformStyle::instantiate requires a QApplication.
     std::string platformName;
     platformName = gArgs.GetArg("-uiplatform", BitcoinGUI::DEFAULT_UIPLATFORM);
     platformStyle =
         PlatformStyle::instantiate(QString::fromStdString(platformName));
     // Fall back to "other" if specified name not found.
     if (!platformStyle) {
         platformStyle = PlatformStyle::instantiate("other");
     }
     assert(platformStyle);
 }
 
 BitcoinApplication::~BitcoinApplication() {
     if (coreThread) {
         qDebug() << __func__ << ": Stopping thread";
         Q_EMIT stopThread();
         coreThread->wait();
         qDebug() << __func__ << ": Stopped thread";
     }
 
     delete window;
     window = 0;
 #ifdef ENABLE_WALLET
     delete paymentServer;
     paymentServer = 0;
 #endif
     delete optionsModel;
     optionsModel = 0;
     delete platformStyle;
     platformStyle = 0;
 }
 
 #ifdef ENABLE_WALLET
 void BitcoinApplication::createPaymentServer() {
     paymentServer = new PaymentServer(this);
 }
 #endif
 
 void BitcoinApplication::createOptionsModel(bool resetSettings) {
     optionsModel = new OptionsModel(m_node, nullptr, resetSettings);
 }
 
 void BitcoinApplication::createWindow(const Config *config,
                                       const NetworkStyle *networkStyle) {
     window = new BitcoinGUI(m_node, config, platformStyle, networkStyle, 0);
 
     pollShutdownTimer = new QTimer(window);
     connect(pollShutdownTimer, SIGNAL(timeout()), window,
             SLOT(detectShutdown()));
 }
 
 void BitcoinApplication::createSplashScreen(const NetworkStyle *networkStyle) {
     SplashScreen *splash = new SplashScreen(m_node, 0, networkStyle);
     // We don't hold a direct pointer to the splash screen after creation, but
     // the splash screen will take care of deleting itself when slotFinish
     // happens.
     splash->show();
     connect(this, SIGNAL(splashFinished(QWidget *)), splash,
             SLOT(slotFinish(QWidget *)));
     connect(this, SIGNAL(requestedShutdown()), splash, SLOT(close()));
 }
 
 void BitcoinApplication::startThread() {
     if (coreThread) {
         return;
     }
     coreThread = new QThread(this);
     BitcoinABC *executor = new BitcoinABC(m_node);
     executor->moveToThread(coreThread);
 
     /*  communication to and from thread */
     connect(executor, SIGNAL(initializeResult(bool)), this,
             SLOT(initializeResult(bool)));
     connect(executor, SIGNAL(shutdownResult()), this, SLOT(shutdownResult()));
     connect(executor, SIGNAL(runawayException(QString)), this,
             SLOT(handleRunawayException(QString)));
 
     // Note on how Qt works: it tries to directly invoke methods if the signal
     // is emitted on the same thread that the target object 'lives' on.
     // But if the target object 'lives' on another thread (executor here does)
     // the SLOT will be invoked asynchronously at a later time in the thread
     // of the target object.  So.. we pass a pointer around.  If you pass
     // a reference around (even if it's non-const) you'll get Qt generating
     // code to copy-construct the parameter in question (Q_DECLARE_METATYPE
     // and qRegisterMetaType generate this code).  For the Config class,
     // which is noncopyable, we can't do this.  So.. we have to pass
     // pointers to Config around.  Make sure Config &/Config * isn't a
     // temporary (eg it lives somewhere aside from the stack) or this will
     // crash because initialize() gets executed in another thread at some
     // unspecified time (after) requestedInitialize() is emitted!
     connect(this,
             SIGNAL(requestedInitialize(Config *, RPCServer *,
                                        HTTPRPCRequestProcessor *)),
             executor,
             SLOT(initialize(Config *, RPCServer *, HTTPRPCRequestProcessor *)));
 
     connect(this, SIGNAL(requestedShutdown()), executor, SLOT(shutdown()));
     /*  make sure executor object is deleted in its own thread */
     connect(this, SIGNAL(stopThread()), executor, SLOT(deleteLater()));
     connect(this, SIGNAL(stopThread()), coreThread, SLOT(quit()));
 
     coreThread->start();
 }
 
 void BitcoinApplication::parameterSetup() {
     m_node.initLogging();
     m_node.initParameterInteraction();
 }
 
 void BitcoinApplication::requestInitialize(
     Config &config, RPCServer &rpcServer,
     HTTPRPCRequestProcessor &httpRPCRequestProcessor) {
     qDebug() << __func__ << ": Requesting initialize";
     startThread();
     // IMPORTANT: config must NOT be a reference to a temporary because below
     // signal may be connected to a slot that will be executed as a queued
     // connection in another thread!
     Q_EMIT requestedInitialize(&config, &rpcServer, &httpRPCRequestProcessor);
 }
 
 void BitcoinApplication::requestShutdown(Config &config) {
     // Show a simple window indicating shutdown status. Do this first as some of
     // the steps may take some time below, for example the RPC console may still
     // be executing a command.
     shutdownWindow.reset(ShutdownWindow::showShutdownWindow(window));
 
     qDebug() << __func__ << ": Requesting shutdown";
     startThread();
     window->hide();
     window->setClientModel(0);
     pollShutdownTimer->stop();
 
 #ifdef ENABLE_WALLET
     window->removeAllWallets();
     for (WalletModel *walletModel : m_wallet_models) {
         delete walletModel;
     }
     m_wallet_models.clear();
 #endif
     delete clientModel;
     clientModel = 0;
 
     m_node.startShutdown();
 
     // Request shutdown from core thread
     Q_EMIT requestedShutdown();
 }
 
 void BitcoinApplication::initializeResult(bool success) {
     qDebug() << __func__ << ": Initialization result: " << success;
     returnValue = success ? EXIT_SUCCESS : EXIT_FAILURE;
     if (!success) {
         // Make sure splash screen doesn't stick around during shutdown.
         Q_EMIT splashFinished(window);
         // Exit first main loop invocation.
         quit();
         return;
     }
     // Log this only after AppInitMain finishes, as then logging setup is
     // guaranteed complete.
     qWarning() << "Platform customization:" << platformStyle->getName();
 #ifdef ENABLE_WALLET
     PaymentServer::LoadRootCAs();
     paymentServer->setOptionsModel(optionsModel);
 #endif
 
     clientModel = new ClientModel(m_node, optionsModel);
     window->setClientModel(clientModel);
 
 #ifdef ENABLE_WALLET
     bool fFirstWallet = true;
     auto wallets = m_node.getWallets();
     for (auto &wallet : wallets) {
         WalletModel *const walletModel = new WalletModel(
             std::move(wallet), m_node, platformStyle, optionsModel);
 
         window->addWallet(walletModel);
         if (fFirstWallet) {
             window->setCurrentWallet(walletModel->getWalletName());
             fFirstWallet = false;
         }
 
         connect(
             walletModel,
             SIGNAL(coinsSent(WalletModel *, SendCoinsRecipient, QByteArray)),
             paymentServer,
             SLOT(fetchPaymentACK(WalletModel *, const SendCoinsRecipient &,
                                  QByteArray)));
 
         m_wallet_models.push_back(walletModel);
     }
 #endif
 
     // If -min option passed, start window minimized.
     if (gArgs.GetBoolArg("-min", false)) {
         window->showMinimized();
     } else {
         window->show();
     }
     Q_EMIT splashFinished(window);
 
 #ifdef ENABLE_WALLET
     // Now that initialization/startup is done, process any command-line
     // bitcoincash: URIs or payment requests:
     connect(paymentServer, SIGNAL(receivedPaymentRequest(SendCoinsRecipient)),
             window, SLOT(handlePaymentRequest(SendCoinsRecipient)));
     connect(window, SIGNAL(receivedURI(QString)), paymentServer,
             SLOT(handleURIOrFile(QString)));
     connect(paymentServer, SIGNAL(message(QString, QString, unsigned int)),
             window, SLOT(message(QString, QString, unsigned int)));
     QTimer::singleShot(100, paymentServer, SLOT(uiReady()));
 #endif
 
     pollShutdownTimer->start(200);
 }
 
 void BitcoinApplication::shutdownResult() {
     // Exit second main loop invocation after shutdown finished.
     quit();
 }
 
 void BitcoinApplication::handleRunawayException(const QString &message) {
     QMessageBox::critical(
         0, "Runaway exception",
         BitcoinGUI::tr("A fatal error occurred. Bitcoin can no longer continue "
                        "safely and will quit.") +
             QString("\n\n") + message);
     ::exit(EXIT_FAILURE);
 }
 
 WId BitcoinApplication::getMainWinId() const {
     if (!window) {
         return 0;
     }
 
     return window->winId();
 }
 
 static void SetupUIArgs() {
 #ifdef ENABLE_WALLET
     gArgs.AddArg("-allowselfsignedrootcertificates",
                  strprintf("Allow self signed root certificates (default: %d)",
                            DEFAULT_SELFSIGNED_ROOTCERTS),
                  true, OptionsCategory::GUI);
 #endif
     gArgs.AddArg(
         "-choosedatadir",
         strprintf(QObject::tr("Choose data directory on startup (default: %d)")
                       .toStdString(),
                   DEFAULT_CHOOSE_DATADIR),
         false, OptionsCategory::GUI);
     gArgs.AddArg(
         "-lang=<lang>",
         QObject::tr(
             "Set language, for example \"de_DE\" (default: system locale)")
             .toStdString(),
         false, OptionsCategory::GUI);
     gArgs.AddArg("-min", QObject::tr("Start minimized").toStdString(), false,
                  OptionsCategory::GUI);
     gArgs.AddArg(
         "-rootcertificates=<file>",
         QObject::tr(
             "Set SSL root certificates for payment request (default: -system-)")
             .toStdString(),
         false, OptionsCategory::GUI);
     gArgs.AddArg(
         "-splash",
         strprintf(QObject::tr("Show splash screen on startup (default: %d)")
                       .toStdString(),
                   DEFAULT_SPLASHSCREEN),
         false, OptionsCategory::GUI);
     gArgs.AddArg(
         "-resetguisettings",
         QObject::tr("Reset all settings changed in the GUI").toStdString(),
         false, OptionsCategory::GUI);
     gArgs.AddArg("-uiplatform",
                  strprintf("Select platform to customize UI for (one of "
                            "windows, macosx, other; default: %s)",
                            BitcoinGUI::DEFAULT_UIPLATFORM),
                  true, OptionsCategory::GUI);
 }
 
 #ifndef BITCOIN_QT_TEST
 
 static void MigrateSettings() {
     assert(!QApplication::applicationName().isEmpty());
 
     static const QString legacyAppName("Bitcoin-Qt"),
 #ifdef Q_OS_DARWIN
         // Macs and/or iOS et al use a domain-style name for Settings
         // files. All other platforms use a simple orgname. This
         // difference is documented in the QSettings class documentation.
         legacyOrg("bitcoin.org");
 #else
         legacyOrg("Bitcoin");
 #endif
     QSettings
         // below picks up settings file location based on orgname,appname
         legacy(legacyOrg, legacyAppName),
         // default c'tor below picks up settings file location based on
         // QApplication::applicationName(), et al -- which was already set
         // in main()
         abc;
 #ifdef Q_OS_DARWIN
     // Disable bogus OSX keys from MacOS system-wide prefs that may cloud our
     // judgement ;) (this behavior is also documented in QSettings docs)
     legacy.setFallbacksEnabled(false);
     abc.setFallbacksEnabled(false);
 #endif
     const QStringList legacyKeys(legacy.allKeys());
 
     // We only migrate settings if we have Core settings but no Bitcoin-ABC
     // settings
     if (!legacyKeys.isEmpty() && abc.allKeys().isEmpty()) {
         for (const QString &key : legacyKeys) {
             // now, copy settings over
             abc.setValue(key, legacy.value(key));
         }
     }
 }
 
 int main(int argc, char *argv[]) {
     SetupEnvironment();
 
     std::unique_ptr<interfaces::Node> node = interfaces::MakeNode();
 
-    /// 1. Parse command-line options. These take precedence over anything else.
-    // Command-line options take precedence:
-    node->setupServerArgs();
-    SetupUIArgs();
-    node->parseParameters(argc, argv);
-
     // Do not refer to data directory yet, this can be overridden by
     // Intro::pickDataDirectory
 
-    /// 2. Basic Qt initialization (not dependent on parameters or
+    /// 1. Basic Qt initialization (not dependent on parameters or
     /// configuration)
     Q_INIT_RESOURCE(bitcoin);
     Q_INIT_RESOURCE(bitcoin_locale);
 
     BitcoinApplication app(*node, argc, argv);
 #if QT_VERSION > 0x050100
     // Generate high-dpi pixmaps
     QApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
 #endif
 #if QT_VERSION >= 0x050600
     QGuiApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
 #endif
 #ifdef Q_OS_MAC
     QApplication::setAttribute(Qt::AA_DontShowIconsInMenus);
 #endif
 
     // Register meta types used for QMetaObject::invokeMethod
     qRegisterMetaType<bool *>();
     //   Need to pass name here as Amount is a typedef (see
     //   http://qt-project.org/doc/qt-5/qmetatype.html#qRegisterMetaType)
     //   IMPORTANT if it is no longer a typedef use the normal variant above
     qRegisterMetaType<Amount>("Amount");
     qRegisterMetaType<std::function<void(void)>>("std::function<void(void)>");
 
     // Need to register any types Qt doesn't know about if you intend
     // to use them with the signal/slot mechanism Qt provides. Even pointers.
     // Note that class Config is noncopyable and so we can't register a
     // non-pointer version of it with Qt, because Qt expects to be able to
     // copy-construct non-pointers to objects for invoking slots
     // behind-the-scenes in the 'Queued' connection case.
     qRegisterMetaType<Config *>();
 
+    /// 2. Parse command-line options. We do this after qt in order to show an
+    /// error if there are problems parsing these
+    // Command-line options take precedence:
+    node->setupServerArgs();
+    SetupUIArgs();
+    std::string error;
+    if (!node->parseParameters(argc, argv, error)) {
+        QMessageBox::critical(
+            0, QObject::tr(PACKAGE_NAME),
+            QObject::tr("Error parsing command line arguments: %1.")
+                .arg(QString::fromStdString(error)));
+        return EXIT_FAILURE;
+    }
+
+    // Now that the QApplication is setup and we have parsed our parameters, we
+    // can set the platform style
+    app.setupPlatformStyle();
+
     /// 3. Application identification
     // must be set before OptionsModel is initialized or translations are
     // loaded, as it is used to locate QSettings.
     // Note: If you move these calls somewhere else, be sure to bring
     // MigrateSettings() below along for the ride.
     QApplication::setOrganizationName(QAPP_ORG_NAME);
     QApplication::setOrganizationDomain(QAPP_ORG_DOMAIN);
     QApplication::setApplicationName(QAPP_APP_NAME_DEFAULT);
     // Migrate settings from core's/our old GUI settings to Bitcoin ABC
     // only if core's exist but Bitcoin ABC's doesn't.
     // NOTE -- this function needs to be called *after* the above 3 lines
     // that set the app orgname and app name! If you move the above 3 lines
     // to elsewhere, take this call with you!
     MigrateSettings();
     GUIUtil::SubstituteFonts(GetLangTerritory());
 
     /// 4. Initialization of translations, so that intro dialog is in user's
     /// language. Now that QSettings are accessible, initialize translations.
     QTranslator qtTranslatorBase, qtTranslator, translatorBase, translator;
     initTranslations(qtTranslatorBase, qtTranslator, translatorBase,
                      translator);
     translationInterface.Translate.connect(Translate);
 
     // Show help message immediately after parsing command-line options (for
     // "-lang") and setting locale, but before showing splash screen.
     if (HelpRequested(gArgs) || gArgs.IsArgSet("-version")) {
         HelpMessageDialog help(*node, nullptr, gArgs.IsArgSet("-version"));
         help.showOrPrint();
         return EXIT_SUCCESS;
     }
 
     /// 5. Now that settings and translations are available, ask user for data
     /// directory. User language is set up: pick a data directory.
     if (!Intro::pickDataDirectory(*node)) {
         return EXIT_SUCCESS;
     }
 
     /// 6. Determine availability of data and blocks directory and parse
     /// bitcoin.conf
     /// - Do not call GetDataDir(true) before this step finishes.
     if (!fs::is_directory(GetDataDir(false))) {
         QMessageBox::critical(
             0, QObject::tr(PACKAGE_NAME),
             QObject::tr(
                 "Error: Specified data directory \"%1\" does not exist.")
                 .arg(QString::fromStdString(gArgs.GetArg("-datadir", ""))));
         return EXIT_FAILURE;
     }
-    try {
-        node->readConfigFiles();
-    } catch (const std::exception &e) {
+    if (!node->readConfigFiles(error)) {
         QMessageBox::critical(
             0, QObject::tr(PACKAGE_NAME),
-            QObject::tr("Error: Cannot parse configuration file: %1. Only use "
-                        "key=value syntax.")
-                .arg(e.what()));
+            QObject::tr("Error: Cannot parse configuration file: %1.")
+                .arg(QString::fromStdString(error)));
         return EXIT_FAILURE;
     }
 
     /// 7. Determine network (and switch to network specific options)
     // - Do not call Params() before this step.
     // - Do this after parsing the configuration file, as the network can be
     // switched there.
     // - QSettings() will use the new application name after this, resulting in
     // network-specific settings.
     // - Needs to be done before createOptionsModel.
 
     // Check for -testnet or -regtest parameter (Params() calls are only valid
     // after this clause)
     try {
         node->selectParams(gArgs.GetChainName());
     } catch (std::exception &e) {
         QMessageBox::critical(0, QObject::tr(PACKAGE_NAME),
                               QObject::tr("Error: %1").arg(e.what()));
         return EXIT_FAILURE;
     }
 #ifdef ENABLE_WALLET
     // Parse URIs on command line -- this can affect Params()
     PaymentServer::ipcParseCommandLine(*node, argc, argv);
 #endif
 
     QScopedPointer<const NetworkStyle> networkStyle(NetworkStyle::instantiate(
         QString::fromStdString(Params().NetworkIDString())));
     assert(!networkStyle.isNull());
     // Allow for separate UI settings for testnets
     QApplication::setApplicationName(networkStyle->getAppName());
     // Re-initialize translations after changing application name (language in
     // network-specific settings can be different)
     initTranslations(qtTranslatorBase, qtTranslator, translatorBase,
                      translator);
 
 #ifdef ENABLE_WALLET
     /// 8. URI IPC sending
     // - Do this early as we don't want to bother initializing if we are just
     // calling IPC
     // - Do this *after* setting up the data directory, as the data directory
     // hash is used in the name
     // of the server.
     // - Do this after creating app and setting up translations, so errors are
     // translated properly.
     if (PaymentServer::ipcSendCommandLine()) {
         exit(EXIT_SUCCESS);
     }
 
     // Start up the payment server early, too, so impatient users that click on
     // bitcoincash: links repeatedly have their payment requests routed to this
     // process:
     app.createPaymentServer();
 #endif
 
     /// 9. Main GUI initialization
     // Install global event filter that makes sure that long tooltips can be
     // word-wrapped.
     app.installEventFilter(
         new GUIUtil::ToolTipToRichTextFilter(TOOLTIP_WRAP_THRESHOLD, &app));
 #if defined(Q_OS_WIN)
     // Install global event filter for processing Windows session related
     // Windows messages (WM_QUERYENDSESSION and WM_ENDSESSION)
     qApp->installNativeEventFilter(new WinShutdownMonitor());
 #endif
     // Install qDebug() message handler to route to debug.log
     qInstallMessageHandler(DebugMessageHandler);
     // Allow parameter interaction before we create the options model
     app.parameterSetup();
     // Load GUI settings from QSettings
     app.createOptionsModel(gArgs.GetBoolArg("-resetguisettings", false));
 
     // Subscribe to global signals from core
     std::unique_ptr<interfaces::Handler> handler =
         node->handleInitMessage(InitMessage);
 
     // Get global config
     Config &config = const_cast<Config &>(GetConfig());
 
     if (gArgs.GetBoolArg("-splash", DEFAULT_SPLASHSCREEN) &&
         !gArgs.GetBoolArg("-min", false)) {
         app.createSplashScreen(networkStyle.data());
     }
 
     RPCServer rpcServer;
     HTTPRPCRequestProcessor httpRPCRequestProcessor(config, rpcServer);
 
     try {
         app.createWindow(&config, networkStyle.data());
         // Perform base initialization before spinning up
         // initialization/shutdown thread. This is acceptable because this
         // function only contains steps that are quick to execute, so the GUI
         // thread won't be held up.
         if (!node->baseInitialize(config)) {
             // A dialog with detailed error will have been shown by InitError()
             return EXIT_FAILURE;
         }
         app.requestInitialize(config, rpcServer, httpRPCRequestProcessor);
 #if defined(Q_OS_WIN)
         WinShutdownMonitor::registerShutdownBlockReason(
             QObject::tr("%1 didn't yet exit safely...")
                 .arg(QObject::tr(PACKAGE_NAME)),
             (HWND)app.getMainWinId());
 #endif
         app.exec();
         app.requestShutdown(config);
         app.exec();
         return app.getReturnValue();
     } catch (const std::exception &e) {
         PrintExceptionContinue(&e, "Runaway exception");
         app.handleRunawayException(
             QString::fromStdString(node->getWarnings("gui")));
     } catch (...) {
         PrintExceptionContinue(nullptr, "Runaway exception");
         app.handleRunawayException(
             QString::fromStdString(node->getWarnings("gui")));
     }
     return EXIT_FAILURE;
 }
 #endif // BITCOIN_QT_TEST
diff --git a/src/rpc/test/server_tests.cpp b/src/rpc/test/server_tests.cpp
index 611d9e04e..c3972e53c 100644
--- a/src/rpc/test/server_tests.cpp
+++ b/src/rpc/test/server_tests.cpp
@@ -1,27 +1,32 @@
 // Copyright (c) 2019 The Bitcoin developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <rpc/server.h>
 #include <test/test_bitcoin.h>
 #include <util.h>
 
+#include <boost/test/unit_test.hpp>
+
 #include <cstdint>
 #include <vector>
 
-#include <boost/test/unit_test.hpp>
-
 BOOST_FIXTURE_TEST_SUITE(server_tests, BasicTestingSetup)
 
 BOOST_AUTO_TEST_CASE(server_IsDeprecatedRPCEnabled) {
     ArgsManager testArgs;
+    testArgs.AddArg("-deprecatedrpc", "", false, OptionsCategory::OPTIONS);
+
     const char *argv_test[] = {"bitcoind", "-deprecatedrpc=foo",
                                "-deprecatedrpc=bar"};
 
-    testArgs.ParseParameters(3, (char **)argv_test);
+    std::string error;
+    BOOST_CHECK_MESSAGE(testArgs.ParseParameters(3, (char **)argv_test, error),
+                        error);
+
     BOOST_CHECK(IsDeprecatedRPCEnabled(testArgs, "foo") == true);
     BOOST_CHECK(IsDeprecatedRPCEnabled(testArgs, "bar") == true);
     BOOST_CHECK(IsDeprecatedRPCEnabled(testArgs, "bob") == false);
 }
 
 BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/test/getarg_tests.cpp b/src/test/getarg_tests.cpp
index feeae90a0..0131d4d3f 100644
--- a/src/test/getarg_tests.cpp
+++ b/src/test/getarg_tests.cpp
@@ -1,161 +1,174 @@
 // Copyright (c) 2012-2015 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <util.h>
 
 #include <test/test_bitcoin.h>
 
 #include <boost/algorithm/string.hpp>
 #include <boost/test/unit_test.hpp>
 
 #include <string>
 #include <vector>
 
 BOOST_FIXTURE_TEST_SUITE(getarg_tests, BasicTestingSetup)
 
 static void ResetArgs(const std::string &strArg) {
     std::vector<std::string> vecArg;
     if (strArg.size())
         boost::split(vecArg, strArg, boost::is_space(),
                      boost::token_compress_on);
 
     // Insert dummy executable name:
     vecArg.insert(vecArg.begin(), "testbitcoin");
 
     // Convert to char*:
     std::vector<const char *> vecChar;
     for (std::string &s : vecArg) {
         vecChar.push_back(s.c_str());
     }
 
-    gArgs.ParseParameters(vecChar.size(), vecChar.data());
+    std::string error;
+    gArgs.ParseParameters(vecChar.size(), vecChar.data(), error);
+}
+
+static void SetupArgs(const std::vector<std::string> &args) {
+    gArgs.ClearArgs();
+    for (const std::string &arg : args) {
+        gArgs.AddArg(arg, "", false, OptionsCategory::OPTIONS);
+    }
 }
 
 BOOST_AUTO_TEST_CASE(boolarg) {
+    SetupArgs({"-foo"});
     ResetArgs("-foo");
     BOOST_CHECK(gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(gArgs.GetBoolArg("-foo", true));
 
     BOOST_CHECK(!gArgs.GetBoolArg("-fo", false));
     BOOST_CHECK(gArgs.GetBoolArg("-fo", true));
 
     BOOST_CHECK(!gArgs.GetBoolArg("-fooo", false));
     BOOST_CHECK(gArgs.GetBoolArg("-fooo", true));
 
     ResetArgs("-foo=0");
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", true));
 
     ResetArgs("-foo=1");
     BOOST_CHECK(gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(gArgs.GetBoolArg("-foo", true));
 
     // New 0.6 feature: auto-map -nosomething to !-something:
     ResetArgs("-nofoo");
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", true));
 
     ResetArgs("-nofoo=1");
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", true));
 
     // -nofoo should win
     ResetArgs("-foo -nofoo");
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", true));
 
     // -nofoo should win
     ResetArgs("-foo=1 -nofoo=1");
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", true));
 
     // -nofoo=0 should win
     ResetArgs("-foo=0 -nofoo=0");
     BOOST_CHECK(gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(gArgs.GetBoolArg("-foo", true));
 
     // New 0.6 feature: treat -- same as -:
     ResetArgs("--foo=1");
     BOOST_CHECK(gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(gArgs.GetBoolArg("-foo", true));
 
     ResetArgs("--nofoo=1");
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", false));
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", true));
 }
 
 BOOST_AUTO_TEST_CASE(stringarg) {
+    SetupArgs({"-foo", "-bar"});
     ResetArgs("");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", ""), "");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", "eleven"), "eleven");
 
     ResetArgs("-foo -bar");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", ""), "");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", "eleven"), "");
 
     ResetArgs("-foo=");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", ""), "");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", "eleven"), "");
 
     ResetArgs("-foo=11");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", ""), "11");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", "eleven"), "11");
 
     ResetArgs("-foo=eleven");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", ""), "eleven");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", "eleven"), "eleven");
 }
 
 BOOST_AUTO_TEST_CASE(intarg) {
+    SetupArgs({"-foo", "-bar"});
     ResetArgs("");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", 11), 11);
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", 0), 0);
 
     ResetArgs("-foo -bar");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", 11), 0);
     BOOST_CHECK_EQUAL(gArgs.GetArg("-bar", 11), 0);
 
     ResetArgs("-foo=11 -bar=12");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", 0), 11);
     BOOST_CHECK_EQUAL(gArgs.GetArg("-bar", 11), 12);
 
     ResetArgs("-foo=NaN -bar=NotANumber");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", 1), 0);
     BOOST_CHECK_EQUAL(gArgs.GetArg("-bar", 11), 0);
 }
 
 BOOST_AUTO_TEST_CASE(doubledash) {
+    SetupArgs({"-foo", "-bar"});
     ResetArgs("--foo");
     BOOST_CHECK_EQUAL(gArgs.GetBoolArg("-foo", false), true);
 
     ResetArgs("--foo=verbose --bar=1");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-foo", ""), "verbose");
     BOOST_CHECK_EQUAL(gArgs.GetArg("-bar", 0), 1);
 }
 
 BOOST_AUTO_TEST_CASE(boolargno) {
+    SetupArgs({"-foo", "-bar"});
     ResetArgs("-nofoo");
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", true));
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", false));
 
     ResetArgs("-nofoo=1");
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", true));
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", false));
 
     ResetArgs("-nofoo=0");
     BOOST_CHECK(gArgs.GetBoolArg("-foo", true));
     BOOST_CHECK(gArgs.GetBoolArg("-foo", false));
 
     // --nofoo should win
     ResetArgs("-foo --nofoo");
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", true));
     BOOST_CHECK(!gArgs.GetBoolArg("-foo", false));
 
     // foo always wins:
     ResetArgs("-nofoo -foo");
     BOOST_CHECK(gArgs.GetBoolArg("-foo", true));
     BOOST_CHECK(gArgs.GetBoolArg("-foo", false));
 }
 
 BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp
index 0a840874c..d13246e75 100644
--- a/src/test/util_tests.cpp
+++ b/src/test/util_tests.cpp
@@ -1,1411 +1,1432 @@
 // Copyright (c) 2011-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <util.h>
 
 #include <clientversion.h>
 #include <primitives/transaction.h>
 #include <sync.h>
 #include <utilmoneystr.h>
 #include <utilstrencodings.h>
 
 #include <test/test_bitcoin.h>
 
 #include <boost/test/unit_test.hpp>
 
 #include <cstdint>
 #ifndef WIN32
 #include <sys/types.h>
 #include <sys/wait.h>
 #endif
 #include <vector>
 
 BOOST_FIXTURE_TEST_SUITE(util_tests, BasicTestingSetup)
 
 BOOST_AUTO_TEST_CASE(util_criticalsection) {
     CCriticalSection cs;
 
     do {
         LOCK(cs);
         break;
 
         BOOST_ERROR("break was swallowed!");
     } while (0);
 
     do {
         TRY_LOCK(cs, lockTest);
         if (lockTest) break;
 
         BOOST_ERROR("break was swallowed!");
     } while (0);
 }
 
 static const uint8_t ParseHex_expected[65] = {
     0x04, 0x67, 0x8a, 0xfd, 0xb0, 0xfe, 0x55, 0x48, 0x27, 0x19, 0x67,
     0xf1, 0xa6, 0x71, 0x30, 0xb7, 0x10, 0x5c, 0xd6, 0xa8, 0x28, 0xe0,
     0x39, 0x09, 0xa6, 0x79, 0x62, 0xe0, 0xea, 0x1f, 0x61, 0xde, 0xb6,
     0x49, 0xf6, 0xbc, 0x3f, 0x4c, 0xef, 0x38, 0xc4, 0xf3, 0x55, 0x04,
     0xe5, 0x1e, 0xc1, 0x12, 0xde, 0x5c, 0x38, 0x4d, 0xf7, 0xba, 0x0b,
     0x8d, 0x57, 0x8a, 0x4c, 0x70, 0x2b, 0x6b, 0xf1, 0x1d, 0x5f};
 BOOST_AUTO_TEST_CASE(util_ParseHex) {
     std::vector<uint8_t> result;
     std::vector<uint8_t> expected(
         ParseHex_expected, ParseHex_expected + sizeof(ParseHex_expected));
     // Basic test vector
     result = ParseHex("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0"
                       "ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d"
                       "578a4c702b6bf11d5f");
     BOOST_CHECK_EQUAL_COLLECTIONS(result.begin(), result.end(),
                                   expected.begin(), expected.end());
 
     // Spaces between bytes must be supported
     result = ParseHex("12 34 56 78");
     BOOST_CHECK(result.size() == 4 && result[0] == 0x12 && result[1] == 0x34 &&
                 result[2] == 0x56 && result[3] == 0x78);
 
     // Leading space must be supported (used in BerkeleyEnvironment::Salvage)
     result = ParseHex(" 89 34 56 78");
     BOOST_CHECK(result.size() == 4 && result[0] == 0x89 && result[1] == 0x34 &&
                 result[2] == 0x56 && result[3] == 0x78);
 
     // Stop parsing at invalid value
     result = ParseHex("1234 invalid 1234");
     BOOST_CHECK(result.size() == 2 && result[0] == 0x12 && result[1] == 0x34);
 }
 
 BOOST_AUTO_TEST_CASE(util_HexStr) {
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected,
                              ParseHex_expected + sizeof(ParseHex_expected)),
                       "04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0"
                       "ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d"
                       "578a4c702b6bf11d5f");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected, ParseHex_expected + 5, true),
                       "04 67 8a fd b0");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected + sizeof(ParseHex_expected),
                              ParseHex_expected + sizeof(ParseHex_expected)),
                       "");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected + sizeof(ParseHex_expected),
                              ParseHex_expected + sizeof(ParseHex_expected),
                              true),
                       "");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected, ParseHex_expected), "");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_expected, ParseHex_expected, true), "");
 
     std::vector<uint8_t> ParseHex_vec(ParseHex_expected, ParseHex_expected + 5);
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_vec, true), "04 67 8a fd b0");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_vec.rbegin(), ParseHex_vec.rend()),
                       "b0fd8a6704");
 
     BOOST_CHECK_EQUAL(HexStr(ParseHex_vec.rbegin(), ParseHex_vec.rend(), true),
                       "b0 fd 8a 67 04");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
         "");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected), true),
         "");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 1),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
         "04");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 1),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected), true),
         "04");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 5),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
         "b0fd8a6704");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 5),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected), true),
         "b0 fd 8a 67 04");
 
     BOOST_CHECK_EQUAL(
         HexStr(std::reverse_iterator<const uint8_t *>(ParseHex_expected + 65),
                std::reverse_iterator<const uint8_t *>(ParseHex_expected)),
         "5f1df16b2b704c8a578d0bbaf74d385cde12c11ee50455f3c438ef4c3fbcf649b6de61"
         "1feae06279a60939e028a8d65c10b73071a6f16719274855feb0fd8a6704");
 }
 
 BOOST_AUTO_TEST_CASE(util_FormatISO8601DateTime) {
     BOOST_CHECK_EQUAL(FormatISO8601DateTime(1317425777),
                       "2011-09-30T23:36:17Z");
 }
 
 BOOST_AUTO_TEST_CASE(util_FormatISO8601Date) {
     BOOST_CHECK_EQUAL(FormatISO8601Date(1317425777), "2011-09-30");
 }
 
 BOOST_AUTO_TEST_CASE(util_FormatISO8601Time) {
     BOOST_CHECK_EQUAL(FormatISO8601Time(1317425777), "23:36:17Z");
 }
 
 struct TestArgsManager : public ArgsManager {
     TestArgsManager() { m_network_only_args.clear(); }
     std::map<std::string, std::vector<std::string>> &GetOverrideArgs() {
         return m_override_args;
     }
     std::map<std::string, std::vector<std::string>> &GetConfigArgs() {
         return m_config_args;
     }
     void ReadConfigString(const std::string str_config) {
         std::istringstream streamConfig(str_config);
         {
             LOCK(cs_args);
             m_config_args.clear();
         }
-        ReadConfigStream(streamConfig);
+        std::string error;
+        ReadConfigStream(streamConfig, error);
     }
     void SetNetworkOnlyArg(const std::string arg) {
         LOCK(cs_args);
         m_network_only_args.insert(arg);
     }
+    void SetupArgs(int argv, const char *args[]) {
+        for (int i = 0; i < argv; ++i) {
+            AddArg(args[i], "", false, OptionsCategory::OPTIONS);
+        }
+    }
 };
 
 BOOST_AUTO_TEST_CASE(util_ParseParameters) {
     TestArgsManager testArgs;
+    const char *avail_args[] = {"-a", "-b", "-ccc", "-d"};
     const char *argv_test[] = {"-ignored",      "-a", "-b",  "-ccc=argument",
                                "-ccc=multiple", "f",  "-d=e"};
 
-    testArgs.ParseParameters(0, (char **)argv_test);
+    std::string error;
+    testArgs.SetupArgs(4, avail_args);
+    testArgs.ParseParameters(0, (char **)argv_test, error);
     BOOST_CHECK(testArgs.GetOverrideArgs().empty() &&
                 testArgs.GetConfigArgs().empty());
 
-    testArgs.ParseParameters(1, (char **)argv_test);
+    testArgs.ParseParameters(1, (char **)argv_test, error);
     BOOST_CHECK(testArgs.GetOverrideArgs().empty() &&
                 testArgs.GetConfigArgs().empty());
 
-    testArgs.ParseParameters(7, (char **)argv_test);
+    testArgs.ParseParameters(7, (char **)argv_test, error);
     // expectation: -ignored is ignored (program name argument),
     // -a, -b and -ccc end up in map, -d ignored because it is after
     // a non-option argument (non-GNU option parsing)
     BOOST_CHECK(testArgs.GetOverrideArgs().size() == 3 &&
                 testArgs.GetConfigArgs().empty());
     BOOST_CHECK(testArgs.IsArgSet("-a") && testArgs.IsArgSet("-b") &&
                 testArgs.IsArgSet("-ccc") && !testArgs.IsArgSet("f") &&
                 !testArgs.IsArgSet("-d"));
     BOOST_CHECK(testArgs.GetOverrideArgs().count("-a") &&
                 testArgs.GetOverrideArgs().count("-b") &&
                 testArgs.GetOverrideArgs().count("-ccc") &&
                 !testArgs.GetOverrideArgs().count("f") &&
                 !testArgs.GetOverrideArgs().count("-d"));
 
     BOOST_CHECK(testArgs.GetOverrideArgs()["-a"].size() == 1);
     BOOST_CHECK(testArgs.GetOverrideArgs()["-a"].front() == "");
     BOOST_CHECK(testArgs.GetOverrideArgs()["-ccc"].size() == 2);
     BOOST_CHECK(testArgs.GetOverrideArgs()["-ccc"].front() == "argument");
     BOOST_CHECK(testArgs.GetOverrideArgs()["-ccc"].back() == "multiple");
     BOOST_CHECK(testArgs.GetArgs("-ccc").size() == 2);
 }
 
 BOOST_AUTO_TEST_CASE(util_GetBoolArg) {
     TestArgsManager testArgs;
+    const char *avail_args[] = {"-a", "-b", "-c", "-d", "-e", "-f"};
     const char *argv_test[] = {"ignored", "-a",       "-nob",   "-c=0",
                                "-d=1",    "-e=false", "-f=true"};
-    testArgs.ParseParameters(7, (char **)argv_test);
+    std::string error;
+    testArgs.SetupArgs(6, avail_args);
+    testArgs.ParseParameters(7, (char **)argv_test, error);
 
     // Each letter should be set.
     for (char opt : "abcdef") {
         BOOST_CHECK(testArgs.IsArgSet({'-', opt}) || !opt);
     }
 
     // Nothing else should be in the map
     BOOST_CHECK(testArgs.GetOverrideArgs().size() == 6 &&
                 testArgs.GetConfigArgs().empty());
 
     // The -no prefix should get stripped on the way in.
     BOOST_CHECK(!testArgs.IsArgSet("-nob"));
 
     // The -b option is flagged as negated, and nothing else is
     BOOST_CHECK(testArgs.IsArgNegated("-b"));
     BOOST_CHECK(!testArgs.IsArgNegated("-a"));
 
     // Check expected values.
     BOOST_CHECK(testArgs.GetBoolArg("-a", false) == true);
     BOOST_CHECK(testArgs.GetBoolArg("-b", true) == false);
     BOOST_CHECK(testArgs.GetBoolArg("-c", true) == false);
     BOOST_CHECK(testArgs.GetBoolArg("-d", false) == true);
     BOOST_CHECK(testArgs.GetBoolArg("-e", true) == false);
     BOOST_CHECK(testArgs.GetBoolArg("-f", true) == false);
 }
 
 BOOST_AUTO_TEST_CASE(util_GetBoolArgEdgeCases) {
     // Test some awful edge cases that hopefully no user will ever exercise.
     TestArgsManager testArgs;
 
     // Params test
+    const char *avail_args[] = {"-foo", "-bar"};
     const char *argv_test[] = {"ignored", "-nofoo", "-foo", "-nobar=0"};
-    testArgs.ParseParameters(4, (char **)argv_test);
+    testArgs.SetupArgs(2, avail_args);
+    std::string error;
+    testArgs.ParseParameters(4, (char **)argv_test, error);
 
     // This was passed twice, second one overrides the negative setting.
     BOOST_CHECK(!testArgs.IsArgNegated("-foo"));
     BOOST_CHECK(testArgs.GetArg("-foo", "xxx") == "");
 
     // A double negative is a positive, and not marked as negated.
     BOOST_CHECK(!testArgs.IsArgNegated("-bar"));
     BOOST_CHECK(testArgs.GetArg("-bar", "xxx") == "1");
 
     // Config test
     const char *conf_test = "nofoo=1\nfoo=1\nnobar=0\n";
-    testArgs.ParseParameters(1, (char **)argv_test);
+    testArgs.ParseParameters(1, (char **)argv_test, error);
     testArgs.ReadConfigString(conf_test);
 
     // This was passed twice, second one overrides the negative setting,
     // and the value.
     BOOST_CHECK(!testArgs.IsArgNegated("-foo"));
     BOOST_CHECK(testArgs.GetArg("-foo", "xxx") == "1");
 
     // A double negative is a positive, and does not count as negated.
     BOOST_CHECK(!testArgs.IsArgNegated("-bar"));
     BOOST_CHECK(testArgs.GetArg("-bar", "xxx") == "1");
 
     // Combined test
     const char *combo_test_args[] = {"ignored", "-nofoo", "-bar"};
     const char *combo_test_conf = "foo=1\nnobar=1\n";
-    testArgs.ParseParameters(3, (char **)combo_test_args);
+    testArgs.ParseParameters(3, (char **)combo_test_args, error);
     testArgs.ReadConfigString(combo_test_conf);
 
     // Command line overrides, but doesn't erase old setting
     BOOST_CHECK(testArgs.IsArgNegated("-foo"));
     BOOST_CHECK(testArgs.GetArg("-foo", "xxx") == "0");
     BOOST_CHECK(testArgs.GetArgs("-foo").size() == 0);
 
     // Command line overrides, but doesn't erase old setting
     BOOST_CHECK(!testArgs.IsArgNegated("-bar"));
     BOOST_CHECK(testArgs.GetArg("-bar", "xxx") == "");
     BOOST_CHECK(testArgs.GetArgs("-bar").size() == 1 &&
                 testArgs.GetArgs("-bar").front() == "");
 }
 
 BOOST_AUTO_TEST_CASE(util_ReadConfigStream) {
     const char *str_config = "a=\n"
                              "b=1\n"
                              "ccc=argument\n"
                              "ccc=multiple\n"
                              "d=e\n"
                              "nofff=1\n"
                              "noggg=0\n"
                              "h=1\n"
                              "noh=1\n"
                              "noi=1\n"
                              "i=1\n"
                              "sec1.ccc=extend1\n"
                              "\n"
                              "[sec1]\n"
                              "ccc=extend2\n"
                              "d=eee\n"
                              "h=1\n"
                              "[sec2]\n"
                              "ccc=extend3\n"
                              "iii=2\n";
 
     TestArgsManager test_args;
+    const char *avail_args[] = {"-a",   "-b",   "-ccc", "-d", "-e",
+                                "-fff", "-ggg", "-h",   "-i", "-iii"};
+    test_args.SetupArgs(10, avail_args);
 
     test_args.ReadConfigString(str_config);
     // expectation: a, b, ccc, d, fff, ggg, h, i end up in map
     // so do sec1.ccc, sec1.d, sec1.h, sec2.ccc, sec2.iii
 
     BOOST_CHECK(test_args.GetOverrideArgs().empty());
     BOOST_CHECK(test_args.GetConfigArgs().size() == 13);
 
     BOOST_CHECK(test_args.GetConfigArgs().count("-a") &&
                 test_args.GetConfigArgs().count("-b") &&
                 test_args.GetConfigArgs().count("-ccc") &&
                 test_args.GetConfigArgs().count("-d") &&
                 test_args.GetConfigArgs().count("-fff") &&
                 test_args.GetConfigArgs().count("-ggg") &&
                 test_args.GetConfigArgs().count("-h") &&
                 test_args.GetConfigArgs().count("-i"));
     BOOST_CHECK(test_args.GetConfigArgs().count("-sec1.ccc") &&
                 test_args.GetConfigArgs().count("-sec1.h") &&
                 test_args.GetConfigArgs().count("-sec2.ccc") &&
                 test_args.GetConfigArgs().count("-sec2.iii"));
 
     BOOST_CHECK(test_args.IsArgSet("-a") && test_args.IsArgSet("-b") &&
                 test_args.IsArgSet("-ccc") && test_args.IsArgSet("-d") &&
                 test_args.IsArgSet("-fff") && test_args.IsArgSet("-ggg") &&
                 test_args.IsArgSet("-h") && test_args.IsArgSet("-i") &&
                 !test_args.IsArgSet("-zzz") && !test_args.IsArgSet("-iii"));
 
     BOOST_CHECK(test_args.GetArg("-a", "xxx") == "" &&
                 test_args.GetArg("-b", "xxx") == "1" &&
                 test_args.GetArg("-ccc", "xxx") == "argument" &&
                 test_args.GetArg("-d", "xxx") == "e" &&
                 test_args.GetArg("-fff", "xxx") == "0" &&
                 test_args.GetArg("-ggg", "xxx") == "1" &&
                 test_args.GetArg("-h", "xxx") == "0" &&
                 test_args.GetArg("-i", "xxx") == "1" &&
                 test_args.GetArg("-zzz", "xxx") == "xxx" &&
                 test_args.GetArg("-iii", "xxx") == "xxx");
 
     for (bool def : {false, true}) {
         BOOST_CHECK(test_args.GetBoolArg("-a", def) &&
                     test_args.GetBoolArg("-b", def) &&
                     !test_args.GetBoolArg("-ccc", def) &&
                     !test_args.GetBoolArg("-d", def) &&
                     !test_args.GetBoolArg("-fff", def) &&
                     test_args.GetBoolArg("-ggg", def) &&
                     !test_args.GetBoolArg("-h", def) &&
                     test_args.GetBoolArg("-i", def) &&
                     test_args.GetBoolArg("-zzz", def) == def &&
                     test_args.GetBoolArg("-iii", def) == def);
     }
 
     BOOST_CHECK(test_args.GetArgs("-a").size() == 1 &&
                 test_args.GetArgs("-a").front() == "");
     BOOST_CHECK(test_args.GetArgs("-b").size() == 1 &&
                 test_args.GetArgs("-b").front() == "1");
     BOOST_CHECK(test_args.GetArgs("-ccc").size() == 2 &&
                 test_args.GetArgs("-ccc").front() == "argument" &&
                 test_args.GetArgs("-ccc").back() == "multiple");
     BOOST_CHECK(test_args.GetArgs("-fff").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-nofff").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-ggg").size() == 1 &&
                 test_args.GetArgs("-ggg").front() == "1");
     BOOST_CHECK(test_args.GetArgs("-noggg").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-h").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-noh").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-i").size() == 1 &&
                 test_args.GetArgs("-i").front() == "1");
     BOOST_CHECK(test_args.GetArgs("-noi").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-zzz").size() == 0);
 
     BOOST_CHECK(!test_args.IsArgNegated("-a"));
     BOOST_CHECK(!test_args.IsArgNegated("-b"));
     BOOST_CHECK(!test_args.IsArgNegated("-ccc"));
     BOOST_CHECK(!test_args.IsArgNegated("-d"));
     BOOST_CHECK(test_args.IsArgNegated("-fff"));
     BOOST_CHECK(!test_args.IsArgNegated("-ggg"));
     // last setting takes precedence
     BOOST_CHECK(test_args.IsArgNegated("-h"));
     // last setting takes precedence
     BOOST_CHECK(!test_args.IsArgNegated("-i"));
     BOOST_CHECK(!test_args.IsArgNegated("-zzz"));
 
     // Test sections work
     test_args.SelectConfigNetwork("sec1");
 
     // same as original
     BOOST_CHECK(test_args.GetArg("-a", "xxx") == "" &&
                 test_args.GetArg("-b", "xxx") == "1" &&
                 test_args.GetArg("-fff", "xxx") == "0" &&
                 test_args.GetArg("-ggg", "xxx") == "1" &&
                 test_args.GetArg("-zzz", "xxx") == "xxx" &&
                 test_args.GetArg("-iii", "xxx") == "xxx");
     // d is overridden
     BOOST_CHECK(test_args.GetArg("-d", "xxx") == "eee");
     // section-specific setting
     BOOST_CHECK(test_args.GetArg("-h", "xxx") == "1");
     // section takes priority for multiple values
     BOOST_CHECK(test_args.GetArg("-ccc", "xxx") == "extend1");
     // check multiple values works
     const std::vector<std::string> sec1_ccc_expected = {"extend1", "extend2",
                                                         "argument", "multiple"};
     const auto &sec1_ccc_res = test_args.GetArgs("-ccc");
     BOOST_CHECK_EQUAL_COLLECTIONS(sec1_ccc_res.begin(), sec1_ccc_res.end(),
                                   sec1_ccc_expected.begin(),
                                   sec1_ccc_expected.end());
 
     test_args.SelectConfigNetwork("sec2");
 
     // same as original
     BOOST_CHECK(test_args.GetArg("-a", "xxx") == "" &&
                 test_args.GetArg("-b", "xxx") == "1" &&
                 test_args.GetArg("-d", "xxx") == "e" &&
                 test_args.GetArg("-fff", "xxx") == "0" &&
                 test_args.GetArg("-ggg", "xxx") == "1" &&
                 test_args.GetArg("-zzz", "xxx") == "xxx" &&
                 test_args.GetArg("-h", "xxx") == "0");
     // section-specific setting
     BOOST_CHECK(test_args.GetArg("-iii", "xxx") == "2");
     // section takes priority for multiple values
     BOOST_CHECK(test_args.GetArg("-ccc", "xxx") == "extend3");
     // check multiple values works
     const std::vector<std::string> sec2_ccc_expected = {"extend3", "argument",
                                                         "multiple"};
     const auto &sec2_ccc_res = test_args.GetArgs("-ccc");
     BOOST_CHECK_EQUAL_COLLECTIONS(sec2_ccc_res.begin(), sec2_ccc_res.end(),
                                   sec2_ccc_expected.begin(),
                                   sec2_ccc_expected.end());
 
     // Test section only options
 
     test_args.SetNetworkOnlyArg("-d");
     test_args.SetNetworkOnlyArg("-ccc");
     test_args.SetNetworkOnlyArg("-h");
 
     test_args.SelectConfigNetwork(CBaseChainParams::MAIN);
     BOOST_CHECK(test_args.GetArg("-d", "xxx") == "e");
     BOOST_CHECK(test_args.GetArgs("-ccc").size() == 2);
     BOOST_CHECK(test_args.GetArg("-h", "xxx") == "0");
 
     test_args.SelectConfigNetwork("sec1");
     BOOST_CHECK(test_args.GetArg("-d", "xxx") == "eee");
     BOOST_CHECK(test_args.GetArgs("-d").size() == 1);
     BOOST_CHECK(test_args.GetArgs("-ccc").size() == 2);
     BOOST_CHECK(test_args.GetArg("-h", "xxx") == "1");
 
     test_args.SelectConfigNetwork("sec2");
     BOOST_CHECK(test_args.GetArg("-d", "xxx") == "xxx");
     BOOST_CHECK(test_args.GetArgs("-d").size() == 0);
     BOOST_CHECK(test_args.GetArgs("-ccc").size() == 1);
     BOOST_CHECK(test_args.GetArg("-h", "xxx") == "0");
 }
 
 BOOST_AUTO_TEST_CASE(util_GetArg) {
     TestArgsManager testArgs;
     testArgs.GetOverrideArgs().clear();
     testArgs.GetOverrideArgs()["strtest1"] = {"string..."};
     // strtest2 undefined on purpose
     testArgs.GetOverrideArgs()["inttest1"] = {"12345"};
     testArgs.GetOverrideArgs()["inttest2"] = {"81985529216486895"};
     // inttest3 undefined on purpose
     testArgs.GetOverrideArgs()["booltest1"] = {""};
     // booltest2 undefined on purpose
     testArgs.GetOverrideArgs()["booltest3"] = {"0"};
     testArgs.GetOverrideArgs()["booltest4"] = {"1"};
 
     // priorities
     testArgs.GetOverrideArgs()["pritest1"] = {"a", "b"};
     testArgs.GetConfigArgs()["pritest2"] = {"a", "b"};
     testArgs.GetOverrideArgs()["pritest3"] = {"a"};
     testArgs.GetConfigArgs()["pritest3"] = {"b"};
     testArgs.GetOverrideArgs()["pritest4"] = {"a", "b"};
     testArgs.GetConfigArgs()["pritest4"] = {"c", "d"};
 
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.GetArg("inttest1", -1), 12345);
     BOOST_CHECK_EQUAL(testArgs.GetArg("inttest2", -1), 81985529216486895LL);
     BOOST_CHECK_EQUAL(testArgs.GetArg("inttest3", -1), -1);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", false), true);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest2", false), false);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest3", false), false);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest4", false), true);
 
     BOOST_CHECK_EQUAL(testArgs.GetArg("pritest1", "default"), "b");
     BOOST_CHECK_EQUAL(testArgs.GetArg("pritest2", "default"), "a");
     BOOST_CHECK_EQUAL(testArgs.GetArg("pritest3", "default"), "a");
     BOOST_CHECK_EQUAL(testArgs.GetArg("pritest4", "default"), "b");
 }
 
 BOOST_AUTO_TEST_CASE(util_ClearArg) {
     TestArgsManager testArgs;
 
     // Clear single string arg
     testArgs.GetOverrideArgs()["strtest1"] = {"string..."};
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "string...");
     testArgs.ClearArg("strtest1");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "default");
 
     // Clear boolean arg
     testArgs.GetOverrideArgs()["booltest1"] = {"1"};
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", false), true);
     testArgs.ClearArg("booltest1");
     BOOST_CHECK_EQUAL(testArgs.GetArg("booltest1", false), false);
 
     // Clear config args only
     testArgs.GetConfigArgs()["strtest2"].push_back("string...");
     testArgs.GetConfigArgs()["strtest2"].push_back("...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 2);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").back(), "...gnirts");
     testArgs.ClearArg("strtest2");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 0);
 
     // Clear both cli args and config args
     testArgs.GetOverrideArgs()["strtest3"].push_back("cli string...");
     testArgs.GetOverrideArgs()["strtest3"].push_back("...gnirts ilc");
     testArgs.GetConfigArgs()["strtest3"].push_back("string...");
     testArgs.GetConfigArgs()["strtest3"].push_back("...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest3", "default"), "...gnirts ilc");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest3").size(), 4);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest3").front(), "cli string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest3").back(), "...gnirts");
     testArgs.ClearArg("strtest3");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest3", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest3").size(), 0);
 }
 
 BOOST_AUTO_TEST_CASE(util_SetArg) {
     TestArgsManager testArgs;
 
     // SoftSetArg
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.SoftSetArg("strtest1", "string..."), true);
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest1").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest1").front(), "string...");
     BOOST_CHECK_EQUAL(testArgs.SoftSetArg("strtest1", "...gnirts"), false);
     testArgs.ClearArg("strtest1");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.SoftSetArg("strtest1", "...gnirts"), true);
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest1", "default"), "...gnirts");
 
     // SoftSetBoolArg
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", false), false);
     BOOST_CHECK_EQUAL(testArgs.SoftSetBoolArg("booltest1", true), true);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", false), true);
     BOOST_CHECK_EQUAL(testArgs.SoftSetBoolArg("booltest1", false), false);
     testArgs.ClearArg("booltest1");
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", true), true);
     BOOST_CHECK_EQUAL(testArgs.SoftSetBoolArg("booltest1", false), true);
     BOOST_CHECK_EQUAL(testArgs.GetBoolArg("booltest1", true), false);
 
     // ForceSetArg
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "default");
     testArgs.ForceSetArg("strtest2", "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "string...");
     testArgs.ForceSetArg("strtest2", "...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "...gnirts");
 
     // ForceSetMultiArg
     testArgs.ForceSetMultiArg("strtest2", "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 2);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").back(), "string...");
     testArgs.ClearArg("strtest2");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "default");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 0);
     testArgs.ForceSetMultiArg("strtest2", "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "string...");
     testArgs.ForceSetMultiArg("strtest2", "one more thing...");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"),
                       "one more thing...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 2);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "string...");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").back(), "one more thing...");
     // If there are multi args, ForceSetArg should erase them
     testArgs.ForceSetArg("strtest2", "...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArg("strtest2", "default"), "...gnirts");
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").size(), 1);
     BOOST_CHECK_EQUAL(testArgs.GetArgs("strtest2").front(), "...gnirts");
 }
 
 BOOST_AUTO_TEST_CASE(util_GetChainName) {
     TestArgsManager test_args;
+    const char *avail_args[] = {"-testnet", "-regtest"};
+    test_args.SetupArgs(2, avail_args);
 
     const char *argv_testnet[] = {"cmd", "-testnet"};
     const char *argv_regtest[] = {"cmd", "-regtest"};
     const char *argv_test_no_reg[] = {"cmd", "-testnet", "-noregtest"};
     const char *argv_both[] = {"cmd", "-testnet", "-regtest"};
 
     // equivalent to "-testnet"
     // regtest in testnet section is ignored
     const char *testnetconf = "testnet=1\nregtest=0\n[test]\nregtest=1";
+    std::string error;
 
-    test_args.ParseParameters(0, (char **)argv_testnet);
+    test_args.ParseParameters(0, (char **)argv_testnet, error);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "main");
 
-    test_args.ParseParameters(2, (char **)argv_testnet);
+    test_args.ParseParameters(2, (char **)argv_testnet, error);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
-    test_args.ParseParameters(2, (char **)argv_regtest);
+    test_args.ParseParameters(2, (char **)argv_regtest, error);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "regtest");
 
-    test_args.ParseParameters(3, (char **)argv_test_no_reg);
+    test_args.ParseParameters(3, (char **)argv_test_no_reg, error);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
-    test_args.ParseParameters(3, (char **)argv_both);
+    test_args.ParseParameters(3, (char **)argv_both, error);
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 
-    test_args.ParseParameters(0, (char **)argv_testnet);
+    test_args.ParseParameters(0, (char **)argv_testnet, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
-    test_args.ParseParameters(2, (char **)argv_testnet);
+    test_args.ParseParameters(2, (char **)argv_testnet, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
-    test_args.ParseParameters(2, (char **)argv_regtest);
+    test_args.ParseParameters(2, (char **)argv_regtest, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 
-    test_args.ParseParameters(3, (char **)argv_test_no_reg);
+    test_args.ParseParameters(3, (char **)argv_test_no_reg, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
-    test_args.ParseParameters(3, (char **)argv_both);
+    test_args.ParseParameters(3, (char **)argv_both, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 
     // check setting the network to test (and thus making
     // [test] regtest=1 potentially relevant) doesn't break things
     test_args.SelectConfigNetwork("test");
 
-    test_args.ParseParameters(0, (char **)argv_testnet);
+    test_args.ParseParameters(0, (char **)argv_testnet, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
-    test_args.ParseParameters(2, (char **)argv_testnet);
+    test_args.ParseParameters(2, (char **)argv_testnet, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
-    test_args.ParseParameters(2, (char **)argv_regtest);
+    test_args.ParseParameters(2, (char **)argv_regtest, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 
-    test_args.ParseParameters(2, (char **)argv_test_no_reg);
+    test_args.ParseParameters(2, (char **)argv_test_no_reg, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_EQUAL(test_args.GetChainName(), "test");
 
-    test_args.ParseParameters(3, (char **)argv_both);
+    test_args.ParseParameters(3, (char **)argv_both, error);
     test_args.ReadConfigString(testnetconf);
     BOOST_CHECK_THROW(test_args.GetChainName(), std::runtime_error);
 }
 
 BOOST_AUTO_TEST_CASE(util_FormatMoney) {
     BOOST_CHECK_EQUAL(FormatMoney(Amount::zero()), "0.00");
     BOOST_CHECK_EQUAL(FormatMoney(123456789 * (COIN / 10000)), "12345.6789");
     BOOST_CHECK_EQUAL(FormatMoney(-1 * COIN), "-1.00");
 
     BOOST_CHECK_EQUAL(FormatMoney(100000000 * COIN), "100000000.00");
     BOOST_CHECK_EQUAL(FormatMoney(10000000 * COIN), "10000000.00");
     BOOST_CHECK_EQUAL(FormatMoney(1000000 * COIN), "1000000.00");
     BOOST_CHECK_EQUAL(FormatMoney(100000 * COIN), "100000.00");
     BOOST_CHECK_EQUAL(FormatMoney(10000 * COIN), "10000.00");
     BOOST_CHECK_EQUAL(FormatMoney(1000 * COIN), "1000.00");
     BOOST_CHECK_EQUAL(FormatMoney(100 * COIN), "100.00");
     BOOST_CHECK_EQUAL(FormatMoney(10 * COIN), "10.00");
     BOOST_CHECK_EQUAL(FormatMoney(COIN), "1.00");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 10), "0.10");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 100), "0.01");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 1000), "0.001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 10000), "0.0001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 100000), "0.00001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 1000000), "0.000001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 10000000), "0.0000001");
     BOOST_CHECK_EQUAL(FormatMoney(COIN / 100000000), "0.00000001");
 }
 
 BOOST_AUTO_TEST_CASE(util_ParseMoney) {
     Amount ret = Amount::zero();
     BOOST_CHECK(ParseMoney("0.0", ret));
     BOOST_CHECK_EQUAL(ret, Amount::zero());
 
     BOOST_CHECK(ParseMoney("12345.6789", ret));
     BOOST_CHECK_EQUAL(ret, 123456789 * (COIN / 10000));
 
     BOOST_CHECK(ParseMoney("100000000.00", ret));
     BOOST_CHECK_EQUAL(ret, 100000000 * COIN);
     BOOST_CHECK(ParseMoney("10000000.00", ret));
     BOOST_CHECK_EQUAL(ret, 10000000 * COIN);
     BOOST_CHECK(ParseMoney("1000000.00", ret));
     BOOST_CHECK_EQUAL(ret, 1000000 * COIN);
     BOOST_CHECK(ParseMoney("100000.00", ret));
     BOOST_CHECK_EQUAL(ret, 100000 * COIN);
     BOOST_CHECK(ParseMoney("10000.00", ret));
     BOOST_CHECK_EQUAL(ret, 10000 * COIN);
     BOOST_CHECK(ParseMoney("1000.00", ret));
     BOOST_CHECK_EQUAL(ret, 1000 * COIN);
     BOOST_CHECK(ParseMoney("100.00", ret));
     BOOST_CHECK_EQUAL(ret, 100 * COIN);
     BOOST_CHECK(ParseMoney("10.00", ret));
     BOOST_CHECK_EQUAL(ret, 10 * COIN);
     BOOST_CHECK(ParseMoney("1.00", ret));
     BOOST_CHECK_EQUAL(ret, COIN);
     BOOST_CHECK(ParseMoney("1", ret));
     BOOST_CHECK_EQUAL(ret, COIN);
     BOOST_CHECK(ParseMoney("0.1", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 10);
     BOOST_CHECK(ParseMoney("0.01", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 100);
     BOOST_CHECK(ParseMoney("0.001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 1000);
     BOOST_CHECK(ParseMoney("0.0001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 10000);
     BOOST_CHECK(ParseMoney("0.00001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 100000);
     BOOST_CHECK(ParseMoney("0.000001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 1000000);
     BOOST_CHECK(ParseMoney("0.0000001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 10000000);
     BOOST_CHECK(ParseMoney("0.00000001", ret));
     BOOST_CHECK_EQUAL(ret, COIN / 100000000);
 
     // Attempted 63 bit overflow should fail
     BOOST_CHECK(!ParseMoney("92233720368.54775808", ret));
 
     // Parsing negative amounts must fail
     BOOST_CHECK(!ParseMoney("-1", ret));
 }
 
 BOOST_AUTO_TEST_CASE(util_IsHex) {
     BOOST_CHECK(IsHex("00"));
     BOOST_CHECK(IsHex("00112233445566778899aabbccddeeffAABBCCDDEEFF"));
     BOOST_CHECK(IsHex("ff"));
     BOOST_CHECK(IsHex("FF"));
 
     BOOST_CHECK(!IsHex(""));
     BOOST_CHECK(!IsHex("0"));
     BOOST_CHECK(!IsHex("a"));
     BOOST_CHECK(!IsHex("eleven"));
     BOOST_CHECK(!IsHex("00xx00"));
     BOOST_CHECK(!IsHex("0x0000"));
 }
 
 BOOST_AUTO_TEST_CASE(util_IsHexNumber) {
     BOOST_CHECK(IsHexNumber("0x0"));
     BOOST_CHECK(IsHexNumber("0"));
     BOOST_CHECK(IsHexNumber("0x10"));
     BOOST_CHECK(IsHexNumber("10"));
     BOOST_CHECK(IsHexNumber("0xff"));
     BOOST_CHECK(IsHexNumber("ff"));
     BOOST_CHECK(IsHexNumber("0xFfa"));
     BOOST_CHECK(IsHexNumber("Ffa"));
     BOOST_CHECK(IsHexNumber("0x00112233445566778899aabbccddeeffAABBCCDDEEFF"));
     BOOST_CHECK(IsHexNumber("00112233445566778899aabbccddeeffAABBCCDDEEFF"));
 
     BOOST_CHECK(!IsHexNumber(""));      // empty string not allowed
     BOOST_CHECK(!IsHexNumber("0x"));    // empty string after prefix not allowed
     BOOST_CHECK(!IsHexNumber("0x0 "));  // no spaces at end,
     BOOST_CHECK(!IsHexNumber(" 0x0"));  // or beginning,
     BOOST_CHECK(!IsHexNumber("0x 0"));  // or middle,
     BOOST_CHECK(!IsHexNumber(" "));     // etc.
     BOOST_CHECK(!IsHexNumber("0x0ga")); // invalid character
     BOOST_CHECK(!IsHexNumber("x0"));    // broken prefix
     BOOST_CHECK(!IsHexNumber("0x0x00")); // two prefixes not allowed
 }
 
 BOOST_AUTO_TEST_CASE(util_seed_insecure_rand) {
     SeedInsecureRand(true);
     for (int mod = 2; mod < 11; mod++) {
         int mask = 1;
         // Really rough binomial confidence approximation.
         int err =
             30 * 10000. / mod * sqrt((1. / mod * (1 - 1. / mod)) / 10000.);
         // mask is 2^ceil(log2(mod))-1
         while (mask < mod - 1) {
             mask = (mask << 1) + 1;
         }
 
         int count = 0;
         // How often does it get a zero from the uniform range [0,mod)?
         for (int i = 0; i < 10000; i++) {
             uint32_t rval;
             do {
                 rval = InsecureRand32() & mask;
             } while (rval >= uint32_t(mod));
             count += rval == 0;
         }
         BOOST_CHECK(count <= 10000 / mod + err);
         BOOST_CHECK(count >= 10000 / mod - err);
     }
 }
 
 BOOST_AUTO_TEST_CASE(util_TimingResistantEqual) {
     BOOST_CHECK(TimingResistantEqual(std::string(""), std::string("")));
     BOOST_CHECK(!TimingResistantEqual(std::string("abc"), std::string("")));
     BOOST_CHECK(!TimingResistantEqual(std::string(""), std::string("abc")));
     BOOST_CHECK(!TimingResistantEqual(std::string("a"), std::string("aa")));
     BOOST_CHECK(!TimingResistantEqual(std::string("aa"), std::string("a")));
     BOOST_CHECK(TimingResistantEqual(std::string("abc"), std::string("abc")));
     BOOST_CHECK(!TimingResistantEqual(std::string("abc"), std::string("aba")));
 }
 
 /* Test strprintf formatting directives.
  * Put a string before and after to ensure sanity of element sizes on stack. */
 #define B "check_prefix"
 #define E "check_postfix"
 BOOST_AUTO_TEST_CASE(strprintf_numbers) {
     int64_t s64t = -9223372036854775807LL;   /* signed 64 bit test value */
     uint64_t u64t = 18446744073709551615ULL; /* unsigned 64 bit test value */
     BOOST_CHECK(strprintf("%s %d %s", B, s64t, E) == B
                 " -9223372036854775807 " E);
     BOOST_CHECK(strprintf("%s %u %s", B, u64t, E) == B
                 " 18446744073709551615 " E);
     BOOST_CHECK(strprintf("%s %x %s", B, u64t, E) == B " ffffffffffffffff " E);
 
     size_t st = 12345678;    /* unsigned size_t test value */
     ssize_t sst = -12345678; /* signed size_t test value */
     BOOST_CHECK(strprintf("%s %d %s", B, sst, E) == B " -12345678 " E);
     BOOST_CHECK(strprintf("%s %u %s", B, st, E) == B " 12345678 " E);
     BOOST_CHECK(strprintf("%s %x %s", B, st, E) == B " bc614e " E);
 
     ptrdiff_t pt = 87654321;   /* positive ptrdiff_t test value */
     ptrdiff_t spt = -87654321; /* negative ptrdiff_t test value */
     BOOST_CHECK(strprintf("%s %d %s", B, spt, E) == B " -87654321 " E);
     BOOST_CHECK(strprintf("%s %u %s", B, pt, E) == B " 87654321 " E);
     BOOST_CHECK(strprintf("%s %x %s", B, pt, E) == B " 5397fb1 " E);
 }
 #undef B
 #undef E
 
 /* Check for mingw/wine issue #3494
  * Remove this test before time.ctime(0xffffffff) == 'Sun Feb  7 07:28:15 2106'
  */
 BOOST_AUTO_TEST_CASE(gettime) {
     BOOST_CHECK((GetTime() & ~0xFFFFFFFFLL) == 0);
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseInt32) {
     int32_t n;
     // Valid values
     BOOST_CHECK(ParseInt32("1234", nullptr));
     BOOST_CHECK(ParseInt32("0", &n) && n == 0);
     BOOST_CHECK(ParseInt32("1234", &n) && n == 1234);
     BOOST_CHECK(ParseInt32("01234", &n) && n == 1234); // no octal
     BOOST_CHECK(ParseInt32("2147483647", &n) && n == 2147483647);
     // (-2147483647 - 1) equals INT_MIN
     BOOST_CHECK(ParseInt32("-2147483648", &n) && n == (-2147483647 - 1));
     BOOST_CHECK(ParseInt32("-1234", &n) && n == -1234);
     // Invalid values
     BOOST_CHECK(!ParseInt32("", &n));
     BOOST_CHECK(!ParseInt32(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseInt32("1 ", &n));
     BOOST_CHECK(!ParseInt32("1a", &n));
     BOOST_CHECK(!ParseInt32("aap", &n));
     BOOST_CHECK(!ParseInt32("0x1", &n)); // no hex
     BOOST_CHECK(!ParseInt32("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseInt32(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseInt32("-2147483649", nullptr));
     BOOST_CHECK(!ParseInt32("2147483648", nullptr));
     BOOST_CHECK(!ParseInt32("-32482348723847471234", nullptr));
     BOOST_CHECK(!ParseInt32("32482348723847471234", nullptr));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseInt64) {
     int64_t n;
     // Valid values
     BOOST_CHECK(ParseInt64("1234", nullptr));
     BOOST_CHECK(ParseInt64("0", &n) && n == 0LL);
     BOOST_CHECK(ParseInt64("1234", &n) && n == 1234LL);
     BOOST_CHECK(ParseInt64("01234", &n) && n == 1234LL); // no octal
     BOOST_CHECK(ParseInt64("2147483647", &n) && n == 2147483647LL);
     BOOST_CHECK(ParseInt64("-2147483648", &n) && n == -2147483648LL);
     BOOST_CHECK(ParseInt64("9223372036854775807", &n) &&
                 n == (int64_t)9223372036854775807);
     BOOST_CHECK(ParseInt64("-9223372036854775808", &n) &&
                 n == (int64_t)-9223372036854775807 - 1);
     BOOST_CHECK(ParseInt64("-1234", &n) && n == -1234LL);
     // Invalid values
     BOOST_CHECK(!ParseInt64("", &n));
     BOOST_CHECK(!ParseInt64(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseInt64("1 ", &n));
     BOOST_CHECK(!ParseInt64("1a", &n));
     BOOST_CHECK(!ParseInt64("aap", &n));
     BOOST_CHECK(!ParseInt64("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseInt64(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseInt64("-9223372036854775809", nullptr));
     BOOST_CHECK(!ParseInt64("9223372036854775808", nullptr));
     BOOST_CHECK(!ParseInt64("-32482348723847471234", nullptr));
     BOOST_CHECK(!ParseInt64("32482348723847471234", nullptr));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseUInt32) {
     uint32_t n;
     // Valid values
     BOOST_CHECK(ParseUInt32("1234", nullptr));
     BOOST_CHECK(ParseUInt32("0", &n) && n == 0);
     BOOST_CHECK(ParseUInt32("1234", &n) && n == 1234);
     BOOST_CHECK(ParseUInt32("01234", &n) && n == 1234); // no octal
     BOOST_CHECK(ParseUInt32("2147483647", &n) && n == 2147483647);
     BOOST_CHECK(ParseUInt32("2147483648", &n) && n == (uint32_t)2147483648);
     BOOST_CHECK(ParseUInt32("4294967295", &n) && n == (uint32_t)4294967295);
     // Invalid values
     BOOST_CHECK(!ParseUInt32("", &n));
     BOOST_CHECK(!ParseUInt32(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseUInt32(" -1", &n));
     BOOST_CHECK(!ParseUInt32("1 ", &n));
     BOOST_CHECK(!ParseUInt32("1a", &n));
     BOOST_CHECK(!ParseUInt32("aap", &n));
     BOOST_CHECK(!ParseUInt32("0x1", &n)); // no hex
     BOOST_CHECK(!ParseUInt32("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseUInt32(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseUInt32("-2147483648", &n));
     BOOST_CHECK(!ParseUInt32("4294967296", &n));
     BOOST_CHECK(!ParseUInt32("-1234", &n));
     BOOST_CHECK(!ParseUInt32("-32482348723847471234", nullptr));
     BOOST_CHECK(!ParseUInt32("32482348723847471234", nullptr));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseUInt64) {
     uint64_t n;
     // Valid values
     BOOST_CHECK(ParseUInt64("1234", nullptr));
     BOOST_CHECK(ParseUInt64("0", &n) && n == 0LL);
     BOOST_CHECK(ParseUInt64("1234", &n) && n == 1234LL);
     BOOST_CHECK(ParseUInt64("01234", &n) && n == 1234LL); // no octal
     BOOST_CHECK(ParseUInt64("2147483647", &n) && n == 2147483647LL);
     BOOST_CHECK(ParseUInt64("9223372036854775807", &n) &&
                 n == 9223372036854775807ULL);
     BOOST_CHECK(ParseUInt64("9223372036854775808", &n) &&
                 n == 9223372036854775808ULL);
     BOOST_CHECK(ParseUInt64("18446744073709551615", &n) &&
                 n == 18446744073709551615ULL);
     // Invalid values
     BOOST_CHECK(!ParseUInt64("", &n));
     BOOST_CHECK(!ParseUInt64(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseUInt64(" -1", &n));
     BOOST_CHECK(!ParseUInt64("1 ", &n));
     BOOST_CHECK(!ParseUInt64("1a", &n));
     BOOST_CHECK(!ParseUInt64("aap", &n));
     BOOST_CHECK(!ParseUInt64("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseUInt64(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseUInt64("-9223372036854775809", nullptr));
     BOOST_CHECK(!ParseUInt64("18446744073709551616", nullptr));
     BOOST_CHECK(!ParseUInt64("-32482348723847471234", nullptr));
     BOOST_CHECK(!ParseUInt64("-2147483648", &n));
     BOOST_CHECK(!ParseUInt64("-9223372036854775808", &n));
     BOOST_CHECK(!ParseUInt64("-1234", &n));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseDouble) {
     double n;
     // Valid values
     BOOST_CHECK(ParseDouble("1234", nullptr));
     BOOST_CHECK(ParseDouble("0", &n) && n == 0.0);
     BOOST_CHECK(ParseDouble("1234", &n) && n == 1234.0);
     BOOST_CHECK(ParseDouble("01234", &n) && n == 1234.0); // no octal
     BOOST_CHECK(ParseDouble("2147483647", &n) && n == 2147483647.0);
     BOOST_CHECK(ParseDouble("-2147483648", &n) && n == -2147483648.0);
     BOOST_CHECK(ParseDouble("-1234", &n) && n == -1234.0);
     BOOST_CHECK(ParseDouble("1e6", &n) && n == 1e6);
     BOOST_CHECK(ParseDouble("-1e6", &n) && n == -1e6);
     // Invalid values
     BOOST_CHECK(!ParseDouble("", &n));
     BOOST_CHECK(!ParseDouble(" 1", &n)); // no padding inside
     BOOST_CHECK(!ParseDouble("1 ", &n));
     BOOST_CHECK(!ParseDouble("1a", &n));
     BOOST_CHECK(!ParseDouble("aap", &n));
     BOOST_CHECK(!ParseDouble("0x1", &n)); // no hex
     const char test_bytes[] = {'1', 0, '1'};
     std::string teststr(test_bytes, sizeof(test_bytes));
     BOOST_CHECK(!ParseDouble(teststr, &n)); // no embedded NULs
     // Overflow and underflow
     BOOST_CHECK(!ParseDouble("-1e10000", nullptr));
     BOOST_CHECK(!ParseDouble("1e10000", nullptr));
 }
 
 BOOST_AUTO_TEST_CASE(test_FormatParagraph) {
     BOOST_CHECK_EQUAL(FormatParagraph("", 79, 0), "");
     BOOST_CHECK_EQUAL(FormatParagraph("test", 79, 0), "test");
     BOOST_CHECK_EQUAL(FormatParagraph(" test", 79, 0), " test");
     BOOST_CHECK_EQUAL(FormatParagraph("test test", 79, 0), "test test");
     BOOST_CHECK_EQUAL(FormatParagraph("test test", 4, 0), "test\ntest");
     BOOST_CHECK_EQUAL(FormatParagraph("testerde test", 4, 0), "testerde\ntest");
     BOOST_CHECK_EQUAL(FormatParagraph("test test", 4, 4), "test\n    test");
 
     // Make sure we don't indent a fully-new line following a too-long line
     // ending
     BOOST_CHECK_EQUAL(FormatParagraph("test test\nabc", 4, 4),
                       "test\n    test\nabc");
 
     BOOST_CHECK_EQUAL(
         FormatParagraph("This_is_a_very_long_test_string_without_any_spaces_so_"
                         "it_should_just_get_returned_as_is_despite_the_length "
                         "until it gets here",
                         79),
         "This_is_a_very_long_test_string_without_any_spaces_so_it_should_just_"
         "get_returned_as_is_despite_the_length\nuntil it gets here");
 
     // Test wrap length is exact
     BOOST_CHECK_EQUAL(
         FormatParagraph("a b c d e f g h i j k l m n o p q r s t u v w x y z 1 "
                         "2 3 4 5 6 7 8 9 a b c de f g h i j k l m n o p",
                         79),
         "a b c d e f g h i j k l m n o p q r s t u v w x y z 1 2 3 4 5 6 7 8 9 "
         "a b c de\nf g h i j k l m n o p");
     BOOST_CHECK_EQUAL(
         FormatParagraph("x\na b c d e f g h i j k l m n o p q r s t u v w x y "
                         "z 1 2 3 4 5 6 7 8 9 a b c de f g h i j k l m n o p",
                         79),
         "x\na b c d e f g h i j k l m n o p q r s t u v w x y z 1 2 3 4 5 6 7 "
         "8 9 a b c de\nf g h i j k l m n o p");
     // Indent should be included in length of lines
     BOOST_CHECK_EQUAL(
         FormatParagraph("x\na b c d e f g h i j k l m n o p q r s t u v w x y "
                         "z 1 2 3 4 5 6 7 8 9 a b c de f g h i j k l m n o p q "
                         "r s t u v w x y z 0 1 2 3 4 5 6 7 8 9 a b c d e fg h "
                         "i j k",
                         79, 4),
         "x\na b c d e f g h i j k l m n o p q r s t u v w x y z 1 2 3 4 5 6 7 "
         "8 9 a b c de\n    f g h i j k l m n o p q r s t u v w x y z 0 1 2 3 4 "
         "5 6 7 8 9 a b c d e fg\n    h i j k");
 
     BOOST_CHECK_EQUAL(
         FormatParagraph("This is a very long test string. This is a second "
                         "sentence in the very long test string.",
                         79),
         "This is a very long test string. This is a second sentence in the "
         "very long\ntest string.");
     BOOST_CHECK_EQUAL(
         FormatParagraph("This is a very long test string.\nThis is a second "
                         "sentence in the very long test string. This is a "
                         "third sentence in the very long test string.",
                         79),
         "This is a very long test string.\nThis is a second sentence in the "
         "very long test string. This is a third\nsentence in the very long "
         "test string.");
     BOOST_CHECK_EQUAL(
         FormatParagraph("This is a very long test string.\n\nThis is a second "
                         "sentence in the very long test string. This is a "
                         "third sentence in the very long test string.",
                         79),
         "This is a very long test string.\n\nThis is a second sentence in the "
         "very long test string. This is a third\nsentence in the very long "
         "test string.");
     BOOST_CHECK_EQUAL(
         FormatParagraph(
             "Testing that normal newlines do not get indented.\nLike here.",
             79),
         "Testing that normal newlines do not get indented.\nLike here.");
 }
 
 BOOST_AUTO_TEST_CASE(test_FormatSubVersion) {
     std::vector<std::string> comments;
     comments.push_back(std::string("comment1"));
     std::vector<std::string> comments2;
     comments2.push_back(std::string("comment1"));
     // Semicolon is discouraged but not forbidden by BIP-0014
     comments2.push_back(SanitizeString(
         std::string("Comment2; .,_?@-; !\"#$%&'()*+/<=>[]\\^`{|}~"),
         SAFE_CHARS_UA_COMMENT));
     BOOST_CHECK_EQUAL(
         FormatSubVersion("Test", 99900, std::vector<std::string>()),
         std::string("/Test:0.9.99/"));
     BOOST_CHECK_EQUAL(FormatSubVersion("Test", 99900, comments),
                       std::string("/Test:0.9.99(comment1)/"));
     BOOST_CHECK_EQUAL(
         FormatSubVersion("Test", 99900, comments2),
         std::string("/Test:0.9.99(comment1; Comment2; .,_?@-; )/"));
 }
 
 BOOST_AUTO_TEST_CASE(test_ParseFixedPoint) {
     int64_t amount = 0;
     BOOST_CHECK(ParseFixedPoint("0", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 0LL);
     BOOST_CHECK(ParseFixedPoint("1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 100000000LL);
     BOOST_CHECK(ParseFixedPoint("0.0", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 0LL);
     BOOST_CHECK(ParseFixedPoint("-0.1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, -10000000LL);
     BOOST_CHECK(ParseFixedPoint("1.1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 110000000LL);
     BOOST_CHECK(ParseFixedPoint("1.10000000000000000", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 110000000LL);
     BOOST_CHECK(ParseFixedPoint("1.1e1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 1100000000LL);
     BOOST_CHECK(ParseFixedPoint("1.1e-1", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 11000000LL);
     BOOST_CHECK(ParseFixedPoint("1000", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 100000000000LL);
     BOOST_CHECK(ParseFixedPoint("-1000", 8, &amount));
     BOOST_CHECK_EQUAL(amount, -100000000000LL);
     BOOST_CHECK(ParseFixedPoint("0.00000001", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 1LL);
     BOOST_CHECK(ParseFixedPoint("0.0000000100000000", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 1LL);
     BOOST_CHECK(ParseFixedPoint("-0.00000001", 8, &amount));
     BOOST_CHECK_EQUAL(amount, -1LL);
     BOOST_CHECK(ParseFixedPoint("1000000000.00000001", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 100000000000000001LL);
     BOOST_CHECK(ParseFixedPoint("9999999999.99999999", 8, &amount));
     BOOST_CHECK_EQUAL(amount, 999999999999999999LL);
     BOOST_CHECK(ParseFixedPoint("-9999999999.99999999", 8, &amount));
     BOOST_CHECK_EQUAL(amount, -999999999999999999LL);
 
     BOOST_CHECK(!ParseFixedPoint("", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("a-1000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-a1000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-1000a", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-01000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("00.1", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint(".1", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("--0.1", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("0.000000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-0.000000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("0.00000001000000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-10000000000.00000000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("10000000000.00000000", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-10000000000.00000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("10000000000.00000001", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-10000000000.00000009", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("10000000000.00000009", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-99999999999.99999999", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("99999909999.09999999", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("92233720368.54775807", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("92233720368.54775808", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-92233720368.54775808", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("-92233720368.54775809", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("1.1e", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("1.1e-", 8, &amount));
     BOOST_CHECK(!ParseFixedPoint("1.", 8, &amount));
 }
 
 static void TestOtherThread(fs::path dirname, std::string lockname,
                             bool *result) {
     *result = LockDirectory(dirname, lockname);
 }
 
 #ifndef WIN32 // Cannot do this test on WIN32 due to lack of fork()
 static constexpr char LockCommand = 'L';
 static constexpr char UnlockCommand = 'U';
 static constexpr char ExitCommand = 'X';
 
 static void TestOtherProcess(fs::path dirname, std::string lockname, int fd) {
     char ch;
     int rv;
     while (true) {
         rv = read(fd, &ch, 1); // Wait for command
         assert(rv == 1);
         switch (ch) {
             case LockCommand:
                 ch = LockDirectory(dirname, lockname);
                 rv = write(fd, &ch, 1);
                 assert(rv == 1);
                 break;
             case UnlockCommand:
                 ReleaseDirectoryLocks();
                 ch = true; // Always succeeds
                 rv = write(fd, &ch, 1);
                 assert(rv == 1);
                 break;
             case ExitCommand:
                 close(fd);
                 exit(0);
             default:
                 assert(0);
         }
     }
 }
 #endif
 
 BOOST_AUTO_TEST_CASE(test_LockDirectory) {
     fs::path dirname = SetDataDir("test_LockDirectory") / fs::unique_path();
     const std::string lockname = ".lock";
 #ifndef WIN32
     // Revert SIGCHLD to default, otherwise boost.test will catch and fail on
     // it: there is BOOST_TEST_IGNORE_SIGCHLD but that only works when defined
     // at build-time of the boost library
     void (*old_handler)(int) = signal(SIGCHLD, SIG_DFL);
 
     // Fork another process for testing before creating the lock, so that we
     // won't fork while holding the lock (which might be undefined, and is not
     // relevant as test case as that is avoided with -daemonize).
     int fd[2];
     BOOST_CHECK_EQUAL(socketpair(AF_UNIX, SOCK_STREAM, 0, fd), 0);
     pid_t pid = fork();
     if (!pid) {
         BOOST_CHECK_EQUAL(close(fd[1]), 0); // Child: close parent end
         TestOtherProcess(dirname, lockname, fd[0]);
     }
     BOOST_CHECK_EQUAL(close(fd[0]), 0); // Parent: close child end
 #endif
     // Lock on non-existent directory should fail
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname), false);
 
     fs::create_directories(dirname);
 
     // Probing lock on new directory should succeed
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), true);
 
     // Persistent lock on new directory should succeed
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname), true);
 
     // Another lock on the directory from the same thread should succeed
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname), true);
 
     // Another lock on the directory from a different thread within the same
     // process should succeed
     bool threadresult;
     std::thread thr(TestOtherThread, dirname, lockname, &threadresult);
     thr.join();
     BOOST_CHECK_EQUAL(threadresult, true);
 #ifndef WIN32
     // Try to acquire lock in child process while we're holding it, this should
     // fail.
     char ch;
     BOOST_CHECK_EQUAL(write(fd[1], &LockCommand, 1), 1);
     BOOST_CHECK_EQUAL(read(fd[1], &ch, 1), 1);
     BOOST_CHECK_EQUAL((bool)ch, false);
 
     // Give up our lock
     ReleaseDirectoryLocks();
     // Probing lock from our side now should succeed, but not hold on to the
     // lock.
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), true);
 
     // Try to acquire the lock in the child process, this should be successful.
     BOOST_CHECK_EQUAL(write(fd[1], &LockCommand, 1), 1);
     BOOST_CHECK_EQUAL(read(fd[1], &ch, 1), 1);
     BOOST_CHECK_EQUAL((bool)ch, true);
 
     // When we try to probe the lock now, it should fail.
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), false);
 
     // Unlock the lock in the child process
     BOOST_CHECK_EQUAL(write(fd[1], &UnlockCommand, 1), 1);
     BOOST_CHECK_EQUAL(read(fd[1], &ch, 1), 1);
     BOOST_CHECK_EQUAL((bool)ch, true);
 
     // When we try to probe the lock now, it should succeed.
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), true);
 
     // Re-lock the lock in the child process, then wait for it to exit, check
     // successful return. After that, we check that exiting the process
     // has released the lock as we would expect by probing it.
     int processstatus;
     BOOST_CHECK_EQUAL(write(fd[1], &LockCommand, 1), 1);
     BOOST_CHECK_EQUAL(write(fd[1], &ExitCommand, 1), 1);
     BOOST_CHECK_EQUAL(waitpid(pid, &processstatus, 0), pid);
     BOOST_CHECK_EQUAL(processstatus, 0);
     BOOST_CHECK_EQUAL(LockDirectory(dirname, lockname, true), true);
 
     // Restore SIGCHLD
     signal(SIGCHLD, old_handler);
     BOOST_CHECK_EQUAL(close(fd[1]), 0); // Close our side of the socketpair
 #endif
     // Clean up
     ReleaseDirectoryLocks();
     fs::remove_all(dirname);
 }
 
 BOOST_AUTO_TEST_CASE(test_DirIsWritable) {
     // Should be able to write to the data dir.
     fs::path tmpdirname = SetDataDir("test_DirIsWritable");
     BOOST_CHECK_EQUAL(DirIsWritable(tmpdirname), true);
 
     // Should not be able to write to a non-existent dir.
     tmpdirname = tmpdirname / fs::unique_path();
     BOOST_CHECK_EQUAL(DirIsWritable(tmpdirname), false);
 
     fs::create_directory(tmpdirname);
     // Should be able to write to it now.
     BOOST_CHECK_EQUAL(DirIsWritable(tmpdirname), true);
     fs::remove(tmpdirname);
 }
 
 template <int F, int T>
 static void CheckConvertBits(const std::vector<uint8_t> &in,
                              const std::vector<uint8_t> &expected) {
     std::vector<uint8_t> outpad;
     bool ret = ConvertBits<F, T, true>(outpad, in.begin(), in.end());
     BOOST_CHECK(ret);
     BOOST_CHECK(outpad == expected);
 
     const bool dopad = (in.size() * F) % T;
     std::vector<uint8_t> outnopad;
     ret = ConvertBits<F, T, false>(outnopad, in.begin(), in.end());
     BOOST_CHECK(ret != dopad);
 
     if (dopad) {
         // We should have skipped the last digit.
         outnopad.push_back(expected.back());
     }
 
     BOOST_CHECK(outnopad == expected);
 
     // Check the other way around.
     std::vector<uint8_t> orignopad;
     ret = ConvertBits<T, F, false>(orignopad, expected.begin(), expected.end());
     BOOST_CHECK(ret == !((expected.size() * T) % F));
     BOOST_CHECK(orignopad == in);
 
     // Check with padding. We may get an extra 0 in that case.
     std::vector<uint8_t> origpad;
     ret = ConvertBits<T, F, true>(origpad, expected.begin(), expected.end());
     BOOST_CHECK(ret);
 
     if (dopad) {
         BOOST_CHECK_EQUAL(origpad.back(), 0);
         origpad.pop_back();
     }
 
     BOOST_CHECK(origpad == in);
 }
 
 BOOST_AUTO_TEST_CASE(test_ConvertBits) {
     CheckConvertBits<8, 5>({}, {});
     CheckConvertBits<8, 5>({0xff}, {0x1f, 0x1c});
     CheckConvertBits<8, 5>({0xff, 0xff}, {0x1f, 0x1f, 0x1f, 0x10});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff}, {0x1f, 0x1f, 0x1f, 0x1f, 0x1e});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff, 0xff},
                            {0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x18});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff, 0xff, 0xff},
                            {0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff, 0xff, 0xff},
                            {0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f});
     CheckConvertBits<8, 5>({0xff, 0xff, 0xff, 0xff, 0xff},
                            {0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f, 0x1f});
     CheckConvertBits<8, 5>({0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef},
                            {0x00, 0x04, 0x11, 0x14, 0x0a, 0x19, 0x1c, 0x09,
                             0x15, 0x0f, 0x06, 0x1e, 0x1e});
 }
 
 BOOST_AUTO_TEST_CASE(test_ToLower) {
     BOOST_CHECK_EQUAL(ToLower('@'), '@');
     BOOST_CHECK_EQUAL(ToLower('A'), 'a');
     BOOST_CHECK_EQUAL(ToLower('Z'), 'z');
     BOOST_CHECK_EQUAL(ToLower('['), '[');
     BOOST_CHECK_EQUAL(ToLower(0), 0);
     BOOST_CHECK_EQUAL(ToLower(255), 255);
 
     std::string testVector;
     Downcase(testVector);
     BOOST_CHECK_EQUAL(testVector, "");
 
     testVector = "#HODL";
     Downcase(testVector);
     BOOST_CHECK_EQUAL(testVector, "#hodl");
 
     testVector = "\x00\xfe\xff";
     Downcase(testVector);
     BOOST_CHECK_EQUAL(testVector, "\x00\xfe\xff");
 }
 
 BOOST_AUTO_TEST_CASE(test_ToUpper) {
     BOOST_CHECK_EQUAL(ToUpper('`'), '`');
     BOOST_CHECK_EQUAL(ToUpper('a'), 'A');
     BOOST_CHECK_EQUAL(ToUpper('z'), 'Z');
     BOOST_CHECK_EQUAL(ToUpper('{'), '{');
     BOOST_CHECK_EQUAL(ToUpper(0), 0);
     BOOST_CHECK_EQUAL(ToUpper(255), 255);
 }
 
 BOOST_AUTO_TEST_CASE(test_Capitalize) {
     BOOST_CHECK_EQUAL(Capitalize(""), "");
     BOOST_CHECK_EQUAL(Capitalize("bitcoin"), "Bitcoin");
     BOOST_CHECK_EQUAL(Capitalize("\x00\xfe\xff"), "\x00\xfe\xff");
 }
 
 BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/util.cpp b/src/util.cpp
index e4109ee43..2ca680b30 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -1,1242 +1,1287 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <util.h>
 
 #include <chainparamsbase.h>
 #include <fs.h>
 #include <random.h>
 #include <serialize.h>
 #include <utilstrencodings.h>
 #include <utiltime.h>
 
 #include <boost/interprocess/sync/file_lock.hpp>
 #include <boost/program_options/detail/config_file.hpp>
 #include <boost/thread.hpp>
 
 #include <openssl/conf.h>
 #include <openssl/rand.h>
 
 #include <cstdarg>
 
 #if (defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__))
 #include <pthread.h>
 #include <pthread_np.h>
 #endif
 
 #ifndef WIN32
 // for posix_fallocate
 #ifdef __linux__
 
 #ifdef _POSIX_C_SOURCE
 #undef _POSIX_C_SOURCE
 #endif
 
 #define _POSIX_C_SOURCE 200112L
 
 #endif // __linux__
 
 #include <algorithm>
 #include <fcntl.h>
 #include <sys/resource.h>
 #include <sys/stat.h>
 
 #else
 
 #ifdef _MSC_VER
 #pragma warning(disable : 4786)
 #pragma warning(disable : 4804)
 #pragma warning(disable : 4805)
 #pragma warning(disable : 4717)
 #endif
 
 #ifdef _WIN32_WINNT
 #undef _WIN32_WINNT
 #endif
 #define _WIN32_WINNT 0x0501
 
 #ifdef _WIN32_IE
 #undef _WIN32_IE
 #endif
 #define _WIN32_IE 0x0501
 
 #define WIN32_LEAN_AND_MEAN 1
 #ifndef NOMINMAX
 #define NOMINMAX
 #endif
 #include <codecvt>
 
 #include <io.h> /* for _commit */
 #include <shlobj.h>
 #endif
 
 #ifdef HAVE_SYS_PRCTL_H
 #include <sys/prctl.h>
 #endif
 
 #ifdef HAVE_MALLOPT_ARENA_MAX
 #include <malloc.h>
 #endif
 
 // Application startup time (used for uptime calculation)
 const int64_t nStartupTime = GetTime();
 
 const char *const BITCOIN_CONF_FILENAME = "bitcoin.conf";
 const char *const BITCOIN_PID_FILENAME = "bitcoind.pid";
 
 ArgsManager gArgs;
 
 CTranslationInterface translationInterface;
 
 /** Init OpenSSL library multithreading support */
 static std::unique_ptr<CCriticalSection[]> ppmutexOpenSSL;
 void locking_callback(int mode, int i, const char *file,
                       int line) NO_THREAD_SAFETY_ANALYSIS {
     if (mode & CRYPTO_LOCK) {
         ENTER_CRITICAL_SECTION(ppmutexOpenSSL[i]);
     } else {
         LEAVE_CRITICAL_SECTION(ppmutexOpenSSL[i]);
     }
 }
 
 // Singleton for wrapping OpenSSL setup/teardown.
 class CInit {
 public:
     CInit() {
         // Init OpenSSL library multithreading support.
         ppmutexOpenSSL.reset(new CCriticalSection[CRYPTO_num_locks()]);
         CRYPTO_set_locking_callback(locking_callback);
 
         // OpenSSL can optionally load a config file which lists optional
         // loadable modules and engines. We don't use them so we don't require
         // the config. However some of our libs may call functions which attempt
         // to load the config file, possibly resulting in an exit() or crash if
         // it is missing or corrupt. Explicitly tell OpenSSL not to try to load
         // the file. The result for our libs will be that the config appears to
         // have been loaded and there are no modules/engines available.
         OPENSSL_no_config();
 
 #ifdef WIN32
         // Seed OpenSSL PRNG with current contents of the screen.
         RAND_screen();
 #endif
 
         // Seed OpenSSL PRNG with performance counter.
         RandAddSeed();
     }
     ~CInit() {
         // Securely erase the memory used by the PRNG.
         RAND_cleanup();
         // Shutdown OpenSSL library multithreading support.
         CRYPTO_set_locking_callback(nullptr);
         // Clear the set of locks now to maintain symmetry with the constructor.
         ppmutexOpenSSL.reset();
     }
 } instance_of_cinit;
 
 /**
  * A map that contains all the currently held directory locks. After successful
  * locking, these will be held here until the global destructor cleans them up
  * and thus automatically unlocks them, or ReleaseDirectoryLocks is called.
  */
 static std::map<std::string, std::unique_ptr<boost::interprocess::file_lock>>
     dir_locks;
 /** Mutex to protect dir_locks. */
 static std::mutex cs_dir_locks;
 
 bool LockDirectory(const fs::path &directory, const std::string lockfile_name,
                    bool probe_only) {
     std::lock_guard<std::mutex> ulock(cs_dir_locks);
     fs::path pathLockFile = directory / lockfile_name;
 
     // If a lock for this directory already exists in the map, don't try to
     // re-lock it
     if (dir_locks.count(pathLockFile.string())) {
         return true;
     }
 
     // Create empty lock file if it doesn't exist.
     FILE *file = fsbridge::fopen(pathLockFile, "a");
     if (file) {
         fclose(file);
     }
 
     try {
         auto lock = std::make_unique<boost::interprocess::file_lock>(
             pathLockFile.string().c_str());
         if (!lock->try_lock()) {
             return false;
         }
         if (!probe_only) {
             // Lock successful and we're not just probing, put it into the map
             dir_locks.emplace(pathLockFile.string(), std::move(lock));
         }
     } catch (const boost::interprocess::interprocess_exception &e) {
         return error("Error while attempting to lock directory %s: %s",
                      directory.string(), e.what());
     }
     return true;
 }
 
 void ReleaseDirectoryLocks() {
     std::lock_guard<std::mutex> ulock(cs_dir_locks);
     dir_locks.clear();
 }
 
 bool DirIsWritable(const fs::path &directory) {
     fs::path tmpFile = directory / fs::unique_path();
 
     FILE *file = fsbridge::fopen(tmpFile, "a");
     if (!file) {
         return false;
     }
 
     fclose(file);
     remove(tmpFile);
 
     return true;
 }
 
 bool CheckDiskSpace(const fs::path &dir, uint64_t nAdditionalBytes) {
     // 50 MiB
     constexpr uint64_t nMinDiskSpace = 52428800;
 
     uint64_t nFreeBytesAvailable = fs::space(dir).available;
     return nFreeBytesAvailable >= nMinDiskSpace + nAdditionalBytes;
 }
 
 /**
  * Interpret a string argument as a boolean.
  *
  * The definition of atoi() requires that non-numeric string values like "foo",
  * return 0. This means that if a user unintentionally supplies a non-integer
  * argument here, the return value is always false. This means that -foo=false
  * does what the user probably expects, but -foo=true is well defined but does
  * not do what they probably expected.
  *
  * The return value of atoi() is undefined when given input not representable as
  * an int. On most systems this means string value between "-2147483648" and
  * "2147483647" are well defined (this method will return true). Setting
  * -txindex=2147483648 on most systems, however, is probably undefined.
  *
  * For a more extensive discussion of this topic (and a wide range of opinions
  * on the Right Way to change this code), see PR12713.
  */
 static bool InterpretBool(const std::string &strValue) {
     if (strValue.empty()) {
         return true;
     }
     return (atoi(strValue) != 0);
 }
 
 /** Internal helper functions for ArgsManager */
 class ArgsManagerHelper {
 public:
     typedef std::map<std::string, std::vector<std::string>> MapArgs;
 
     /** Determine whether to use config settings in the default section,
      *  See also comments around ArgsManager::ArgsManager() below. */
     static inline bool UseDefaultSection(const ArgsManager &am,
                                          const std::string &arg) {
         return (am.m_network == CBaseChainParams::MAIN ||
                 am.m_network_only_args.count(arg) == 0);
     }
 
     /** Convert regular argument into the network-specific setting */
     static inline std::string NetworkArg(const ArgsManager &am,
                                          const std::string &arg) {
         assert(arg.length() > 1 && arg[0] == '-');
         return "-" + am.m_network + "." + arg.substr(1);
     }
 
     /** Find arguments in a map and add them to a vector */
     static inline void AddArgs(std::vector<std::string> &res,
                                const MapArgs &map_args,
                                const std::string &arg) {
         auto it = map_args.find(arg);
         if (it != map_args.end()) {
             res.insert(res.end(), it->second.begin(), it->second.end());
         }
     }
 
     /**
      * Return true/false if an argument is set in a map, and also
      * return the first (or last) of the possibly multiple values it has
      */
     static inline std::pair<bool, std::string>
     GetArgHelper(const MapArgs &map_args, const std::string &arg,
                  bool getLast = false) {
         auto it = map_args.find(arg);
 
         if (it == map_args.end() || it->second.empty()) {
             return std::make_pair(false, std::string());
         }
 
         if (getLast) {
             return std::make_pair(true, it->second.back());
         } else {
             return std::make_pair(true, it->second.front());
         }
     }
 
     /**
      * Get the string value of an argument, returning a pair of a boolean
      * indicating the argument was found, and the value for the argument
      * if it was found (or the empty string if not found).
      */
     static inline std::pair<bool, std::string> GetArg(const ArgsManager &am,
                                                       const std::string &arg) {
         LOCK(am.cs_args);
         std::pair<bool, std::string> found_result(false, std::string());
 
         // We pass "true" to GetArgHelper in order to return the last
         // argument value seen from the command line (so "bitcoind -foo=bar
         // -foo=baz" gives GetArg(am,"foo")=={true,"baz"}
         found_result = GetArgHelper(am.m_override_args, arg, true);
         if (found_result.first) {
             return found_result;
         }
 
         // But in contrast we return the first argument seen in a config file,
         // so "foo=bar \n foo=baz" in the config file gives
         // GetArg(am,"foo")={true,"bar"}
         if (!am.m_network.empty()) {
             found_result = GetArgHelper(am.m_config_args, NetworkArg(am, arg));
             if (found_result.first) {
                 return found_result;
             }
         }
 
         if (UseDefaultSection(am, arg)) {
             found_result = GetArgHelper(am.m_config_args, arg);
             if (found_result.first) {
                 return found_result;
             }
         }
 
         return found_result;
     }
 
     /* Special test for -testnet and -regtest args, because we don't want to be
      * confused by craziness like "[regtest] testnet=1"
      */
     static inline bool GetNetBoolArg(const ArgsManager &am,
                                      const std::string &net_arg) {
         std::pair<bool, std::string> found_result(false, std::string());
         found_result = GetArgHelper(am.m_override_args, net_arg, true);
         if (!found_result.first) {
             found_result = GetArgHelper(am.m_config_args, net_arg, true);
             if (!found_result.first) {
                 // not set
                 return false;
             }
         }
         // is set, so evaluate
         return InterpretBool(found_result.second);
     }
 };
 
 /**
  * Interpret -nofoo as if the user supplied -foo=0.
  *
  * This method also tracks when the -no form was supplied, and if so, checks
  * whether there was a double-negative (-nofoo=0 -> -foo=1).
  *
  * If there was not a double negative, it removes the "no" from the key, and
  * returns true, indicating the caller should clear the args vector to indicate
  * a negated option.
  *
  * If there was a double negative, it removes "no" from the key, sets the value
  * to "1" and returns false.
  *
  * If there was no "no", it leaves key and value untouched and returns false.
  *
  * Where an option was negated can be later checked using the IsArgNegated()
  * method. One use case for this is to have a way to disable options that are
  * not normally boolean (e.g. using -nodebuglogfile to request that debug log
  * output is not sent to any file at all).
  */
 static bool InterpretNegatedOption(std::string &key, std::string &val) {
     assert(key[0] == '-');
 
     size_t option_index = key.find('.');
     if (option_index == std::string::npos) {
         option_index = 1;
     } else {
         ++option_index;
     }
     if (key.substr(option_index, 2) == "no") {
         bool bool_val = InterpretBool(val);
         key.erase(option_index, 2);
         if (!bool_val) {
             // Double negatives like -nofoo=0 are supported (but discouraged)
             LogPrintf(
                 "Warning: parsed potentially confusing double-negative %s=%s\n",
                 key, val);
             val = "1";
         } else {
             return true;
         }
     }
     return false;
 }
 
 ArgsManager::ArgsManager()
     : /* These options would cause cross-contamination if values for mainnet
        * were used while running on regtest/testnet (or vice-versa).
        * Setting them as section_only_args ensures that sharing a config file
        * between mainnet and regtest/testnet won't cause problems due to these
        * parameters by accident. */
       m_network_only_args{
           "-addnode", "-connect", "-port",   "-bind",
           "-rpcport", "-rpcbind", "-wallet",
       } {
     // nothing to do
 }
 
 void ArgsManager::WarnForSectionOnlyArgs() {
     // if there's no section selected, don't worry
     if (m_network.empty()) {
         return;
     }
 
     // if it's okay to use the default section for this network, don't worry
     if (m_network == CBaseChainParams::MAIN) {
         return;
     }
 
     for (const auto &arg : m_network_only_args) {
         std::pair<bool, std::string> found_result;
 
         // if this option is overridden it's fine
         found_result = ArgsManagerHelper::GetArgHelper(m_override_args, arg);
         if (found_result.first) {
             continue;
         }
 
         // if there's a network-specific value for this option, it's fine
         found_result = ArgsManagerHelper::GetArgHelper(
             m_config_args, ArgsManagerHelper::NetworkArg(*this, arg));
         if (found_result.first) {
             continue;
         }
 
         // if there isn't a default value for this option, it's fine
         found_result = ArgsManagerHelper::GetArgHelper(m_config_args, arg);
         if (!found_result.first) {
             continue;
         }
 
         // otherwise, issue a warning
         LogPrintf("Warning: Config setting for %s only applied on %s network "
                   "when in [%s] section.\n",
                   arg, m_network, m_network);
     }
 }
 
 void ArgsManager::SelectConfigNetwork(const std::string &network) {
     m_network = network;
 }
 
-void ArgsManager::ParseParameters(int argc, const char *const argv[]) {
+bool ArgsManager::ParseParameters(int argc, const char *const argv[],
+                                  std::string &error) {
     LOCK(cs_args);
     m_override_args.clear();
 
     for (int i = 1; i < argc; i++) {
         std::string key(argv[i]);
         std::string val;
         size_t is_index = key.find('=');
         if (is_index != std::string::npos) {
             val = key.substr(is_index + 1);
             key.erase(is_index);
         }
 #ifdef WIN32
         std::transform(key.begin(), key.end(), key.begin(), ::tolower);
         if (key[0] == '/') {
             key[0] = '-';
         }
 #endif
 
         if (key[0] != '-') {
             break;
         }
 
         // Transform --foo to -foo
         if (key.length() > 1 && key[1] == '-') {
             key.erase(0, 1);
         }
 
         // Check for -nofoo
         if (InterpretNegatedOption(key, val)) {
             m_override_args[key].clear();
         } else {
             m_override_args[key].push_back(val);
         }
+
+        // Check that the arg is known
+        if (!(IsSwitchChar(key[0]) && key.size() == 1)) {
+            if (!IsArgKnown(key, error)) {
+                error = strprintf("Invalid parameter %s", key.c_str());
+                return false;
+            }
+        }
     }
 
     // we do not allow -includeconf from command line, so we clear it here
     auto it = m_override_args.find("-includeconf");
     if (it != m_override_args.end()) {
         if (it->second.size() > 0) {
             for (const auto &ic : it->second) {
                 fprintf(stderr,
                         "warning: -includeconf cannot be used from "
                         "commandline; ignoring -includeconf=%s\n",
                         ic.c_str());
             }
             m_override_args.erase(it);
         }
     }
+    return true;
+}
+
+bool ArgsManager::IsArgKnown(const std::string &key, std::string &error) {
+    size_t option_index = key.find('.');
+    std::string arg_no_net;
+    if (option_index == std::string::npos) {
+        arg_no_net = key;
+    } else {
+        arg_no_net =
+            std::string("-") + key.substr(option_index + 1, std::string::npos);
+    }
+
+    for (const auto &arg_map : m_available_args) {
+        if (arg_map.second.count(arg_no_net)) {
+            return true;
+        }
+    }
+    return false;
 }
 
 std::vector<std::string> ArgsManager::GetArgs(const std::string &strArg) const {
     std::vector<std::string> result = {};
     // special case
     if (IsArgNegated(strArg)) {
         return result;
     }
 
     LOCK(cs_args);
 
     ArgsManagerHelper::AddArgs(result, m_override_args, strArg);
     if (!m_network.empty()) {
         ArgsManagerHelper::AddArgs(
             result, m_config_args,
             ArgsManagerHelper::NetworkArg(*this, strArg));
     }
 
     if (ArgsManagerHelper::UseDefaultSection(*this, strArg)) {
         ArgsManagerHelper::AddArgs(result, m_config_args, strArg);
     }
 
     return result;
 }
 
 bool ArgsManager::IsArgSet(const std::string &strArg) const {
     // special case
     if (IsArgNegated(strArg)) {
         return true;
     }
     return ArgsManagerHelper::GetArg(*this, strArg).first;
 }
 
 bool ArgsManager::IsArgNegated(const std::string &strArg) const {
     LOCK(cs_args);
 
     const auto &ov = m_override_args.find(strArg);
     if (ov != m_override_args.end()) {
         return ov->second.empty();
     }
 
     if (!m_network.empty()) {
         const auto &cfs =
             m_config_args.find(ArgsManagerHelper::NetworkArg(*this, strArg));
         if (cfs != m_config_args.end()) {
             return cfs->second.empty();
         }
     }
 
     const auto &cf = m_config_args.find(strArg);
     if (cf != m_config_args.end()) {
         return cf->second.empty();
     }
 
     return false;
 }
 
 std::string ArgsManager::GetArg(const std::string &strArg,
                                 const std::string &strDefault) const {
     if (IsArgNegated(strArg)) {
         return "0";
     }
     std::pair<bool, std::string> found_res =
         ArgsManagerHelper::GetArg(*this, strArg);
     if (found_res.first) {
         return found_res.second;
     }
     return strDefault;
 }
 
 int64_t ArgsManager::GetArg(const std::string &strArg, int64_t nDefault) const {
     if (IsArgNegated(strArg)) {
         return 0;
     }
     std::pair<bool, std::string> found_res =
         ArgsManagerHelper::GetArg(*this, strArg);
     if (found_res.first) {
         return atoi64(found_res.second);
     }
     return nDefault;
 }
 
 bool ArgsManager::GetBoolArg(const std::string &strArg, bool fDefault) const {
     if (IsArgNegated(strArg)) {
         return false;
     }
     std::pair<bool, std::string> found_res =
         ArgsManagerHelper::GetArg(*this, strArg);
     if (found_res.first) {
         return InterpretBool(found_res.second);
     }
     return fDefault;
 }
 
 bool ArgsManager::SoftSetArg(const std::string &strArg,
                              const std::string &strValue) {
     LOCK(cs_args);
     if (IsArgSet(strArg)) {
         return false;
     }
     ForceSetArg(strArg, strValue);
     return true;
 }
 
 bool ArgsManager::SoftSetBoolArg(const std::string &strArg, bool fValue) {
     if (fValue) {
         return SoftSetArg(strArg, std::string("1"));
     } else {
         return SoftSetArg(strArg, std::string("0"));
     }
 }
 
 void ArgsManager::ForceSetArg(const std::string &strArg,
                               const std::string &strValue) {
     LOCK(cs_args);
     m_override_args[strArg] = {strValue};
 }
 
 /**
  * This function is only used for testing purpose so
  * so we should not worry about element uniqueness and
  * integrity of mapMultiArgs data structure
  */
 void ArgsManager::ForceSetMultiArg(const std::string &strArg,
                                    const std::string &strValue) {
     LOCK(cs_args);
     m_override_args[strArg].push_back(strValue);
 }
 
 void ArgsManager::AddArg(const std::string &name, const std::string &help,
                          const bool debug_only, const OptionsCategory &cat) {
     // Split arg name from its help param
     size_t eq_index = name.find('=');
     if (eq_index == std::string::npos) {
         eq_index = name.size();
     }
 
     std::map<std::string, Arg> &arg_map = m_available_args[cat];
     auto ret = arg_map.emplace(
         name.substr(0, eq_index),
         Arg(name.substr(eq_index, name.size() - eq_index), help, debug_only));
     // Make sure an insertion actually happened.
     assert(ret.second);
 }
 
 void ArgsManager::ClearArg(const std::string &strArg) {
     LOCK(cs_args);
     m_override_args.erase(strArg);
     m_config_args.erase(strArg);
 }
 
 std::string ArgsManager::GetHelpMessage() {
     const bool show_debug = gArgs.GetBoolArg("-help-debug", false);
 
     std::string usage = "";
     for (const auto &arg_map : m_available_args) {
         switch (arg_map.first) {
             case OptionsCategory::OPTIONS:
                 usage += HelpMessageGroup("Options:");
                 break;
             case OptionsCategory::CONNECTION:
                 usage += HelpMessageGroup("Connection options:");
                 break;
             case OptionsCategory::ZMQ:
                 usage += HelpMessageGroup("ZeroMQ notification options:");
                 break;
             case OptionsCategory::DEBUG_TEST:
                 usage += HelpMessageGroup("Debugging/Testing options:");
                 break;
             case OptionsCategory::NODE_RELAY:
                 usage += HelpMessageGroup("Node relay options:");
                 break;
             case OptionsCategory::BLOCK_CREATION:
                 usage += HelpMessageGroup("Block creation options:");
                 break;
             case OptionsCategory::RPC:
                 usage += HelpMessageGroup("RPC server options:");
                 break;
             case OptionsCategory::WALLET:
                 usage += HelpMessageGroup("Wallet options:");
                 break;
             case OptionsCategory::WALLET_DEBUG_TEST:
                 if (show_debug) {
                     usage +=
                         HelpMessageGroup("Wallet debugging/testing options:");
                 }
                 break;
             case OptionsCategory::CHAINPARAMS:
                 usage += HelpMessageGroup("Chain selection options:");
                 break;
             case OptionsCategory::GUI:
                 usage += HelpMessageGroup("UI Options:");
                 break;
             case OptionsCategory::COMMANDS:
                 usage += HelpMessageGroup("Commands:");
                 break;
             case OptionsCategory::REGISTER_COMMANDS:
                 usage += HelpMessageGroup("Register Commands:");
                 break;
             default:
                 break;
         }
 
         // When we get to the hidden options, stop
         if (arg_map.first == OptionsCategory::HIDDEN) {
             break;
         }
 
         for (const auto &arg : arg_map.second) {
             if (show_debug || !arg.second.m_debug_only) {
                 std::string name;
                 if (arg.second.m_help_param.empty()) {
                     name = arg.first;
                 } else {
                     name = arg.first + arg.second.m_help_param;
                 }
                 usage += HelpMessageOpt(name, arg.second.m_help_text);
             }
         }
     }
     return usage;
 }
 
 bool HelpRequested(const ArgsManager &args) {
     return args.IsArgSet("-?") || args.IsArgSet("-h") || args.IsArgSet("-help");
 }
 
 static const int screenWidth = 79;
 static const int optIndent = 2;
 static const int msgIndent = 7;
 
 std::string HelpMessageGroup(const std::string &message) {
     return std::string(message) + std::string("\n\n");
 }
 
 std::string HelpMessageOpt(const std::string &option,
                            const std::string &message) {
     return std::string(optIndent, ' ') + std::string(option) +
            std::string("\n") + std::string(msgIndent, ' ') +
            FormatParagraph(message, screenWidth - msgIndent, msgIndent) +
            std::string("\n\n");
 }
 
 static std::string FormatException(const std::exception *pex,
                                    const char *pszThread) {
 #ifdef WIN32
     char pszModule[MAX_PATH] = "";
     GetModuleFileNameA(nullptr, pszModule, sizeof(pszModule));
 #else
     const char *pszModule = "bitcoin";
 #endif
     if (pex) {
         return strprintf("EXCEPTION: %s       \n%s       \n%s in %s       \n",
                          typeid(*pex).name(), pex->what(), pszModule,
                          pszThread);
     } else {
         return strprintf("UNKNOWN EXCEPTION       \n%s in %s       \n",
                          pszModule, pszThread);
     }
 }
 
 void PrintExceptionContinue(const std::exception *pex, const char *pszThread) {
     std::string message = FormatException(pex, pszThread);
     LogPrintf("\n\n************************\n%s\n", message);
     fprintf(stderr, "\n\n************************\n%s\n", message.c_str());
 }
 
 fs::path GetDefaultDataDir() {
 // Windows < Vista: C:\Documents and Settings\Username\Application Data\Bitcoin
 // Windows >= Vista: C:\Users\Username\AppData\Roaming\Bitcoin
 // Mac: ~/Library/Application Support/Bitcoin
 // Unix: ~/.bitcoin
 #ifdef WIN32
     // Windows
     return GetSpecialFolderPath(CSIDL_APPDATA) / "Bitcoin";
 #else
     fs::path pathRet;
     char *pszHome = getenv("HOME");
     if (pszHome == nullptr || strlen(pszHome) == 0) {
         pathRet = fs::path("/");
     } else {
         pathRet = fs::path(pszHome);
     }
 #ifdef MAC_OSX
     // Mac
     return pathRet / "Library/Application Support/Bitcoin";
 #else
     // Unix
     return pathRet / ".bitcoin";
 #endif
 #endif
 }
 
 static fs::path g_blocks_path_cache_net_specific;
 static fs::path pathCached;
 static fs::path pathCachedNetSpecific;
 static CCriticalSection csPathCached;
 
 const fs::path &GetBlocksDir() {
 
     LOCK(csPathCached);
 
     fs::path &path = g_blocks_path_cache_net_specific;
 
     // This can be called during exceptions by LogPrintf(), so we cache the
     // value so we don't have to do memory allocations after that.
     if (!path.empty()) {
         return path;
     }
 
     if (gArgs.IsArgSet("-blocksdir")) {
         path = fs::system_complete(gArgs.GetArg("-blocksdir", ""));
         if (!fs::is_directory(path)) {
             path = "";
             return path;
         }
     } else {
         path = GetDataDir(false);
     }
 
     path /= BaseParams().DataDir();
     path /= "blocks";
     fs::create_directories(path);
     return path;
 }
 
 const fs::path &GetDataDir(bool fNetSpecific) {
     LOCK(csPathCached);
 
     fs::path &path = fNetSpecific ? pathCachedNetSpecific : pathCached;
 
     // This can be called during exceptions by LogPrintf(), so we cache the
     // value so we don't have to do memory allocations after that.
     if (!path.empty()) {
         return path;
     }
 
     if (gArgs.IsArgSet("-datadir")) {
         path = fs::system_complete(gArgs.GetArg("-datadir", ""));
         if (!fs::is_directory(path)) {
             path = "";
             return path;
         }
     } else {
         path = GetDefaultDataDir();
     }
 
     if (fNetSpecific) {
         path /= BaseParams().DataDir();
     }
 
     if (fs::create_directories(path)) {
         // This is the first run, create wallets subdirectory too
         //
         // TODO: this is an ugly way to create the wallets/ directory and
         // really shouldn't be done here. Once this is fixed, please
         // also remove the corresponding line in bitcoind.cpp AppInit.
         // See more info at:
         // https://reviews.bitcoinabc.org/D3312
         fs::create_directories(path / "wallets");
     }
 
     return path;
 }
 
 void ClearDatadirCache() {
     LOCK(csPathCached);
 
     pathCached = fs::path();
     pathCachedNetSpecific = fs::path();
     g_blocks_path_cache_net_specific = fs::path();
 }
 
 fs::path GetConfigFile(const std::string &confPath) {
     fs::path pathConfigFile(confPath);
     if (!pathConfigFile.is_complete()) {
         pathConfigFile = GetDataDir(false) / pathConfigFile;
     }
 
     return pathConfigFile;
 }
 
-void ArgsManager::ReadConfigStream(std::istream &stream) {
+bool ArgsManager::ReadConfigStream(std::istream &stream, std::string &error,
+                                   bool ignore_invalid_keys) {
     LOCK(cs_args);
 
     std::set<std::string> setOptions;
     setOptions.insert("*");
 
     for (boost::program_options::detail::config_file_iterator
              it(stream, setOptions),
          end;
          it != end; ++it) {
         std::string strKey = std::string("-") + it->string_key;
         std::string strValue = it->value[0];
+
         if (InterpretNegatedOption(strKey, strValue)) {
             m_config_args[strKey].clear();
         } else {
             m_config_args[strKey].push_back(strValue);
         }
+
+        // Check that the arg is known
+        if (!IsArgKnown(strKey, error) && !ignore_invalid_keys) {
+            error = strprintf("Invalid configuration value %s",
+                              it->string_key.c_str());
+            return false;
+        }
     }
+    return true;
 }
 
-void ArgsManager::ReadConfigFiles() {
+bool ArgsManager::ReadConfigFiles(std::string &error,
+                                  bool ignore_invalid_keys) {
     {
         LOCK(cs_args);
         m_config_args.clear();
     }
 
     const std::string confPath = GetArg("-conf", BITCOIN_CONF_FILENAME);
     fs::ifstream stream(GetConfigFile(confPath));
 
     // ok to not have a config file
     if (stream.good()) {
-        ReadConfigStream(stream);
+        if (!ReadConfigStream(stream, error, ignore_invalid_keys)) {
+            return false;
+        }
         // if there is an -includeconf in the override args, but it is empty,
         // that means the user passed '-noincludeconf' on the command line, in
         // which case we should not include anything
         bool emptyIncludeConf;
         {
             LOCK(cs_args);
             emptyIncludeConf = m_override_args.count("-includeconf") == 0;
         }
         if (emptyIncludeConf) {
             std::vector<std::string> includeconf(GetArgs("-includeconf"));
             {
                 // We haven't set m_network yet (that happens in
                 // SelectParams()), so manually check for network.includeconf
                 // args.
                 std::vector<std::string> includeconf_net(GetArgs(
                     std::string("-") + GetChainName() + ".includeconf"));
                 includeconf.insert(includeconf.end(), includeconf_net.begin(),
                                    includeconf_net.end());
             }
 
             for (const std::string &to_include : includeconf) {
                 fs::ifstream include_config(GetConfigFile(to_include));
                 if (include_config.good()) {
-                    ReadConfigStream(include_config);
+                    if (!ReadConfigStream(include_config, error,
+                                          ignore_invalid_keys)) {
+                        return false;
+                    }
                     LogPrintf("Included configuration file %s\n",
                               to_include.c_str());
                 } else {
                     fprintf(stderr, "Failed to include configuration file %s\n",
                             to_include.c_str());
                 }
             }
         }
     }
 
     // If datadir is changed in .conf file:
     ClearDatadirCache();
     if (!fs::is_directory(GetDataDir(false))) {
-        throw std::runtime_error(
-            strprintf("specified data directory \"%s\" does not exist.",
-                      gArgs.GetArg("-datadir", "").c_str()));
+        error = strprintf("specified data directory \"%s\" does not exist.",
+                          gArgs.GetArg("-datadir", "").c_str());
+        return false;
     }
+    return true;
 }
 
 std::string ArgsManager::GetChainName() const {
     bool fRegTest = ArgsManagerHelper::GetNetBoolArg(*this, "-regtest");
     bool fTestNet = ArgsManagerHelper::GetNetBoolArg(*this, "-testnet");
 
     if (fTestNet && fRegTest) {
         throw std::runtime_error(
             "Invalid combination of -regtest and -testnet.");
     }
     if (fRegTest) {
         return CBaseChainParams::REGTEST;
     }
     if (fTestNet) {
         return CBaseChainParams::TESTNET;
     }
     return CBaseChainParams::MAIN;
 }
 
 #ifndef WIN32
 fs::path GetPidFile() {
     fs::path pathPidFile(gArgs.GetArg("-pid", BITCOIN_PID_FILENAME));
     if (!pathPidFile.is_complete()) {
         pathPidFile = GetDataDir() / pathPidFile;
     }
     return pathPidFile;
 }
 
 void CreatePidFile(const fs::path &path, pid_t pid) {
     FILE *file = fsbridge::fopen(path, "w");
     if (file) {
         fprintf(file, "%d\n", pid);
         fclose(file);
     }
 }
 #endif
 
 bool RenameOver(fs::path src, fs::path dest) {
 #ifdef WIN32
     return MoveFileExA(src.string().c_str(), dest.string().c_str(),
                        MOVEFILE_REPLACE_EXISTING) != 0;
 #else
     int rc = std::rename(src.string().c_str(), dest.string().c_str());
     return (rc == 0);
 #endif /* WIN32 */
 }
 
 /**
  * Ignores exceptions thrown by Boost's create_directories if the requested
  * directory exists. Specifically handles case where path p exists, but it
  * wasn't possible for the user to write to the parent directory.
  */
 bool TryCreateDirectories(const fs::path &p) {
     try {
         return fs::create_directories(p);
     } catch (const fs::filesystem_error &) {
         if (!fs::exists(p) || !fs::is_directory(p)) {
             throw;
         }
     }
 
     // create_directory didn't create the directory, it had to have existed
     // already.
     return false;
 }
 
 bool FileCommit(FILE *file) {
     // harmless if redundantly called
     if (fflush(file) != 0) {
         LogPrintf("%s: fflush failed: %d\n", __func__, errno);
         return false;
     }
 #ifdef WIN32
     HANDLE hFile = (HANDLE)_get_osfhandle(_fileno(file));
     if (FlushFileBuffers(hFile) == 0) {
         LogPrintf("%s: FlushFileBuffers failed: %d\n", __func__,
                   GetLastError());
         return false;
     }
 #else
 #if defined(__linux__) || defined(__NetBSD__)
     // Ignore EINVAL for filesystems that don't support sync
     if (fdatasync(fileno(file)) != 0 && errno != EINVAL) {
         LogPrintf("%s: fdatasync failed: %d\n", __func__, errno);
         return false;
     }
 #elif defined(__APPLE__) && defined(F_FULLFSYNC)
     // Manpage says "value other than -1" is returned on success
     if (fcntl(fileno(file), F_FULLFSYNC, 0) == -1) {
         LogPrintf("%s: fcntl F_FULLFSYNC failed: %d\n", __func__, errno);
         return false;
     }
 #else
     if (fsync(fileno(file)) != 0 && errno != EINVAL) {
         LogPrintf("%s: fsync failed: %d\n", __func__, errno);
         return false;
     }
 #endif
 #endif
     return true;
 }
 
 bool TruncateFile(FILE *file, unsigned int length) {
 #if defined(WIN32)
     return _chsize(_fileno(file), length) == 0;
 #else
     return ftruncate(fileno(file), length) == 0;
 #endif
 }
 
 /**
  * This function tries to raise the file descriptor limit to the requested
  * number. It returns the actual file descriptor limit (which may be more or
  * less than nMinFD)
  */
 int RaiseFileDescriptorLimit(int nMinFD) {
 #if defined(WIN32)
     return 2048;
 #else
     struct rlimit limitFD;
     if (getrlimit(RLIMIT_NOFILE, &limitFD) != -1) {
         if (limitFD.rlim_cur < (rlim_t)nMinFD) {
             limitFD.rlim_cur = nMinFD;
             if (limitFD.rlim_cur > limitFD.rlim_max) {
                 limitFD.rlim_cur = limitFD.rlim_max;
             }
             setrlimit(RLIMIT_NOFILE, &limitFD);
             getrlimit(RLIMIT_NOFILE, &limitFD);
         }
         return limitFD.rlim_cur;
     }
     // getrlimit failed, assume it's fine.
     return nMinFD;
 #endif
 }
 
 /**
  * This function tries to make a particular range of a file allocated
  * (corresponding to disk space) it is advisory, and the range specified in the
  * arguments will never contain live data.
  */
 void AllocateFileRange(FILE *file, unsigned int offset, unsigned int length) {
 #if defined(WIN32)
     // Windows-specific version.
     HANDLE hFile = (HANDLE)_get_osfhandle(_fileno(file));
     LARGE_INTEGER nFileSize;
     int64_t nEndPos = (int64_t)offset + length;
     nFileSize.u.LowPart = nEndPos & 0xFFFFFFFF;
     nFileSize.u.HighPart = nEndPos >> 32;
     SetFilePointerEx(hFile, nFileSize, 0, FILE_BEGIN);
     SetEndOfFile(hFile);
 #elif defined(MAC_OSX)
     // OSX specific version.
     fstore_t fst;
     fst.fst_flags = F_ALLOCATECONTIG;
     fst.fst_posmode = F_PEOFPOSMODE;
     fst.fst_offset = 0;
     fst.fst_length = (off_t)offset + length;
     fst.fst_bytesalloc = 0;
     if (fcntl(fileno(file), F_PREALLOCATE, &fst) == -1) {
         fst.fst_flags = F_ALLOCATEALL;
         fcntl(fileno(file), F_PREALLOCATE, &fst);
     }
     ftruncate(fileno(file), fst.fst_length);
 #elif defined(__linux__)
     // Version using posix_fallocate.
     off_t nEndPos = (off_t)offset + length;
     posix_fallocate(fileno(file), 0, nEndPos);
 #else
     // Fallback version
     // TODO: just write one byte per block
     static const char buf[65536] = {};
     fseek(file, offset, SEEK_SET);
     while (length > 0) {
         unsigned int now = 65536;
         if (length < now) {
             now = length;
         }
         // Allowed to fail; this function is advisory anyway.
         fwrite(buf, 1, now, file);
         length -= now;
     }
 #endif
 }
 
 #ifdef WIN32
 fs::path GetSpecialFolderPath(int nFolder, bool fCreate) {
     char pszPath[MAX_PATH] = "";
 
     if (SHGetSpecialFolderPathA(nullptr, pszPath, nFolder, fCreate)) {
         return fs::path(pszPath);
     }
 
     LogPrintf(
         "SHGetSpecialFolderPathA() failed, could not obtain requested path.\n");
     return fs::path("");
 }
 #endif
 
 void runCommand(const std::string &strCommand) {
     if (strCommand.empty()) {
         return;
     }
 #ifndef WIN32
     int nErr = ::system(strCommand.c_str());
 #else
     int nErr = ::_wsystem(
         std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>, wchar_t>()
             .from_bytes(strCommand)
             .c_str());
 #endif
     if (nErr) {
         LogPrintf("runCommand error: system(%s) returned %d\n", strCommand,
                   nErr);
     }
 }
 
 void RenameThread(const char *name) {
 #if defined(PR_SET_NAME)
     // Only the first 15 characters are used (16 - NUL terminator)
     ::prctl(PR_SET_NAME, name, 0, 0, 0);
 #elif (defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__))
     pthread_set_name_np(pthread_self(), name);
 
 #elif defined(MAC_OSX)
     pthread_setname_np(name);
 #else
     // Prevent warnings for unused parameters...
     (void)name;
 #endif
 }
 
 void SetupEnvironment() {
 #ifdef HAVE_MALLOPT_ARENA_MAX
     // glibc-specific: On 32-bit systems set the number of arenas to 1. By
     // default, since glibc 2.10, the C library will create up to two heap
     // arenas per core. This is known to cause excessive virtual address space
     // usage in our usage. Work around it by setting the maximum number of
     // arenas to 1.
     if (sizeof(void *) == 4) {
         mallopt(M_ARENA_MAX, 1);
     }
 #endif
 // On most POSIX systems (e.g. Linux, but not BSD) the environment's locale may
 // be invalid, in which case the "C" locale is used as fallback.
 #if !defined(WIN32) && !defined(MAC_OSX) && !defined(__FreeBSD__) &&           \
     !defined(__OpenBSD__)
     try {
         // Raises a runtime error if current locale is invalid.
         std::locale("");
     } catch (const std::runtime_error &) {
         setenv("LC_ALL", "C", 1);
     }
 #endif
     // The path locale is lazy initialized and to avoid deinitialization errors
     // in multithreading environments, it is set explicitly by the main thread.
     // A dummy locale is used to extract the internal default locale, used by
     // fs::path, which is then used to explicitly imbue the path.
     std::locale loc = fs::path::imbue(std::locale::classic());
 #ifndef WIN32
     fs::path::imbue(loc);
 #else
     fs::path::imbue(std::locale(loc, new std::codecvt_utf8_utf16<wchar_t>()));
 #endif
 }
 
 bool SetupNetworking() {
 #ifdef WIN32
     // Initialize Windows Sockets.
     WSADATA wsadata;
     int ret = WSAStartup(MAKEWORD(2, 2), &wsadata);
     if (ret != NO_ERROR || LOBYTE(wsadata.wVersion) != 2 ||
         HIBYTE(wsadata.wVersion) != 2) {
         return false;
     }
 #endif
     return true;
 }
 
 int GetNumCores() {
     return boost::thread::physical_concurrency();
 }
 
 std::string CopyrightHolders(const std::string &strPrefix) {
     return strPrefix +
            strprintf(_(COPYRIGHT_HOLDERS), _(COPYRIGHT_HOLDERS_SUBSTITUTION));
 }
 
 // Obtain the application startup time (used for uptime calculation)
 int64_t GetStartupTime() {
     return nStartupTime;
 }
diff --git a/src/util.h b/src/util.h
index 217f654dc..6b20f2c7b 100644
--- a/src/util.h
+++ b/src/util.h
@@ -1,345 +1,357 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 /**
  * Server/client environment: argument handling, config file parsing,
  * thread wrappers, startup time
  */
 #ifndef BITCOIN_UTIL_H
 #define BITCOIN_UTIL_H
 
 #if defined(HAVE_CONFIG_H)
 #include <config/bitcoin-config.h>
 #endif
 
 #include <compat.h>
 #include <fs.h>
 #include <logging.h>
 #include <sync.h>
 #include <tinyformat.h>
 #include <utiltime.h>
 
 #include <boost/signals2/signal.hpp>
 #include <boost/thread/condition_variable.hpp> // for boost::thread_interrupted
 
 #include <atomic>
 #include <cstdint>
 #include <exception>
 #include <map>
 #include <set>
 #include <string>
 #include <unordered_set>
 #include <vector>
 
 // Application startup time (used for uptime calculation)
 int64_t GetStartupTime();
 
 /** Signals for translation. */
 class CTranslationInterface {
 public:
     /** Translate a message to the native language of the user. */
     boost::signals2::signal<std::string(const char *psz)> Translate;
 };
 
 extern CTranslationInterface translationInterface;
 
 extern const char *const BITCOIN_CONF_FILENAME;
 extern const char *const BITCOIN_PID_FILENAME;
 
 /**
  * Translation function: Call Translate signal on UI interface, which returns a
  * boost::optional result. If no translation slot is registered, nothing is
  * returned, and simply return the input.
  */
 inline std::string _(const char *psz) {
     boost::optional<std::string> rv = translationInterface.Translate(psz);
     return rv ? (*rv) : psz;
 }
 
 void SetupEnvironment();
 bool SetupNetworking();
 
 template <typename... Args> bool error(const char *fmt, const Args &... args) {
     LogPrintf("ERROR: " + tfm::format(fmt, args...) + "\n");
     return false;
 }
 
 void PrintExceptionContinue(const std::exception *pex, const char *pszThread);
 bool FileCommit(FILE *file);
 bool TruncateFile(FILE *file, unsigned int length);
 int RaiseFileDescriptorLimit(int nMinFD);
 void AllocateFileRange(FILE *file, unsigned int offset, unsigned int length);
 bool RenameOver(fs::path src, fs::path dest);
 bool LockDirectory(const fs::path &directory, const std::string lockfile_name,
                    bool probe_only = false);
 bool DirIsWritable(const fs::path &directory);
 bool CheckDiskSpace(const fs::path &dir, uint64_t nAdditionalBytes = 0);
 
 /**
  * Release all directory locks. This is used for unit testing only, at runtime
  * the global destructor will take care of the locks.
  */
 void ReleaseDirectoryLocks();
 
 bool TryCreateDirectories(const fs::path &p);
 fs::path GetDefaultDataDir();
 // The blocks directory is always net specific.
 const fs::path &GetBlocksDir();
 const fs::path &GetDataDir(bool fNetSpecific = true);
 void ClearDatadirCache();
 fs::path GetConfigFile(const std::string &confPath);
 #ifndef WIN32
 fs::path GetPidFile();
 void CreatePidFile(const fs::path &path, pid_t pid);
 #endif
 #ifdef WIN32
 fs::path GetSpecialFolderPath(int nFolder, bool fCreate = true);
 #endif
 void runCommand(const std::string &strCommand);
 
 inline bool IsSwitchChar(char c) {
 #ifdef WIN32
     return c == '-' || c == '/';
 #else
     return c == '-';
 #endif
 }
 
 enum class OptionsCategory {
     OPTIONS,
     CONNECTION,
     WALLET,
     WALLET_DEBUG_TEST,
     ZMQ,
     DEBUG_TEST,
     CHAINPARAMS,
     NODE_RELAY,
     BLOCK_CREATION,
     RPC,
     GUI,
     COMMANDS,
     REGISTER_COMMANDS,
 
     // Always the last option to avoid printing these in the help
     HIDDEN,
 };
 
 class ArgsManager {
 protected:
     friend class ArgsManagerHelper;
 
     struct Arg {
         std::string m_help_param;
         std::string m_help_text;
         bool m_debug_only;
 
         Arg(const std::string &help_param, const std::string &help_text,
             bool debug_only)
             : m_help_param(help_param), m_help_text(help_text),
               m_debug_only(debug_only){};
     };
 
     mutable CCriticalSection cs_args;
     std::map<std::string, std::vector<std::string>> m_override_args;
     std::map<std::string, std::vector<std::string>> m_config_args;
     std::string m_network;
     std::set<std::string> m_network_only_args;
     std::map<OptionsCategory, std::map<std::string, Arg>> m_available_args;
 
-    void ReadConfigStream(std::istream &stream);
+    bool ReadConfigStream(std::istream &stream, std::string &error,
+                          bool ignore_invalid_keys = false);
 
 public:
     ArgsManager();
 
     /**
      * Select the network in use
      */
     void SelectConfigNetwork(const std::string &network);
 
-    void ParseParameters(int argc, const char *const argv[]);
-    void ReadConfigFiles();
+    bool ParseParameters(int argc, const char *const argv[],
+                         std::string &error);
+    bool ReadConfigFiles(std::string &error, bool ignore_invalid_keys = false);
 
     /**
      * Log warnings for options in m_section_only_args when they are specified
      * in the default section but not overridden on the command line or in a
      * network-specific section in the config file.
      */
     void WarnForSectionOnlyArgs();
 
     /**
      * Return a vector of strings of the given argument
      *
      * @param strArg Argument to get (e.g. "-foo")
      * @return command-line arguments
      */
     std::vector<std::string> GetArgs(const std::string &strArg) const;
 
     /**
      * Return true if the given argument has been manually set.
      *
      * @param strArg Argument to get (e.g. "-foo")
      * @return true if the argument has been set
      */
     bool IsArgSet(const std::string &strArg) const;
 
     /**
      * Return true if the argument was originally passed as a negated option,
      * i.e. -nofoo.
      *
      * @param strArg Argument to get (e.g. "-foo")
      * @return true if the argument was passed negated
      */
     bool IsArgNegated(const std::string &strArg) const;
 
     /**
      * Return string argument or default value.
      *
      * @param strArg Argument to get (e.g. "-foo")
      * @param default (e.g. "1")
      * @return command-line argument or default value
      */
     std::string GetArg(const std::string &strArg,
                        const std::string &strDefault) const;
 
     /**
      * Return integer argument or default value.
      *
      * @param strArg Argument to get (e.g. "-foo")
      * @param default (e.g. 1)
      * @return command-line argument (0 if invalid number) or default value
      */
     int64_t GetArg(const std::string &strArg, int64_t nDefault) const;
 
     /**
      * Return boolean argument or default value.
      *
      * @param strArg Argument to get (e.g. "-foo")
      * @param default (true or false)
      * @return command-line argument or default value
      */
     bool GetBoolArg(const std::string &strArg, bool fDefault) const;
 
     /**
      * Set an argument if it doesn't already have a value.
      *
      * @param strArg Argument to set (e.g. "-foo")
      * @param strValue Value (e.g. "1")
      * @return true if argument gets set, false if it already had a value
      */
     bool SoftSetArg(const std::string &strArg, const std::string &strValue);
 
     /**
      * Set a boolean argument if it doesn't already have a value.
      *
      * @param strArg Argument to set (e.g. "-foo")
      * @param fValue Value (e.g. false)
      * @return true if argument gets set, false if it already had a value
      */
     bool SoftSetBoolArg(const std::string &strArg, bool fValue);
 
     // Forces an arg setting. Called by SoftSetArg() if the arg hasn't already
     // been set. Also called directly in testing.
     void ForceSetArg(const std::string &strArg, const std::string &strValue);
 
     // Forces a multi arg setting, used only in testing
     void ForceSetMultiArg(const std::string &strArg,
                           const std::string &strValue);
 
     /**
      * Looks for -regtest, -testnet and returns the appropriate BIP70 chain
      * name.
      * @return CBaseChainParams::MAIN by default; raises runtime error if an
      * invalid combination is given.
      */
     std::string GetChainName() const;
 
     /**
      * Add argument
      */
     void AddArg(const std::string &name, const std::string &help,
                 const bool debug_only, const OptionsCategory &cat);
 
     // Remove an arg setting, used only in testing
     void ClearArg(const std::string &strArg);
 
+    /**
+     * Clear available arguments
+     */
+    void ClearArgs() { m_available_args.clear(); }
+
     /**
      * Get the help string
      */
     std::string GetHelpMessage();
+
+    /**
+     * Check whether we know of this arg
+     */
+    bool IsArgKnown(const std::string &key, std::string &error);
 };
 
 extern ArgsManager gArgs;
 
 /**
  * @return true if help has been requested via a command-line arg
  */
 bool HelpRequested(const ArgsManager &args);
 
 /**
  * Format a string to be used as group of options in help messages.
  *
  * @param message Group name (e.g. "RPC server options:")
  * @return the formatted string
  */
 std::string HelpMessageGroup(const std::string &message);
 
 /**
  * Format a string to be used as option description in help messages.
  *
  * @param option Option message (e.g. "-rpcuser=<user>")
  * @param message Option description (e.g. "Username for JSON-RPC connections")
  * @return the formatted string
  */
 std::string HelpMessageOpt(const std::string &option,
                            const std::string &message);
 
 /**
  * Return the number of physical cores available on the current system.
  * @note This does not count virtual cores, such as those provided by
  * HyperThreading when boost is newer than 1.56.
  */
 int GetNumCores();
 
 void RenameThread(const char *name);
 
 /**
  * .. and a wrapper that just calls func once
  */
 template <typename Callable> void TraceThread(const char *name, Callable func) {
     std::string s = strprintf("bitcoin-%s", name);
     RenameThread(s.c_str());
     try {
         LogPrintf("%s thread start\n", name);
         func();
         LogPrintf("%s thread exit\n", name);
     } catch (const boost::thread_interrupted &) {
         LogPrintf("%s thread interrupt\n", name);
         throw;
     } catch (const std::exception &e) {
         PrintExceptionContinue(&e, name);
         throw;
     } catch (...) {
         PrintExceptionContinue(nullptr, name);
         throw;
     }
 }
 
 std::string CopyrightHolders(const std::string &strPrefix);
 
 namespace util {
 
 //! Simplification of std insertion
 template <typename Tdst, typename Tsrc>
 inline void insert(Tdst &dst, const Tsrc &src) {
     dst.insert(dst.begin(), src.begin(), src.end());
 }
 template <typename TsetT, typename Tsrc>
 inline void insert(std::set<TsetT> &dst, const Tsrc &src) {
     dst.insert(src.begin(), src.end());
 }
 
 } // namespace util
 
 #endif // BITCOIN_UTIL_H
diff --git a/test/functional/feature_help.py b/test/functional/feature_help.py
index 9e1acc580..92d4d587c 100755
--- a/test/functional/feature_help.py
+++ b/test/functional/feature_help.py
@@ -1,50 +1,63 @@
 #!/usr/bin/env python3
 # Copyright (c) 2018 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Verify that starting bitcoin with -h works as expected."""
 import subprocess
 
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import assert_equal
 
 
 class HelpTest(BitcoinTestFramework):
     def set_test_params(self):
         self.setup_clean_chain = True
         self.num_nodes = 1
 
     def setup_network(self):
         self.add_nodes(self.num_nodes)
         # Don't start the node
 
     def run_test(self):
         self.log.info("Start bitcoin with -h for help text")
         self.nodes[0].start(extra_args=['-h'],
                             stderr=subprocess.PIPE, stdout=subprocess.PIPE)
         # Node should exit immediately and output help to stdout.
         ret_code = self.nodes[0].process.wait(timeout=1)
         assert_equal(ret_code, 0)
         output = self.nodes[0].process.stdout.read()
         assert b'Options' in output
         self.log.info("Help text received: {} (...)".format(output[0:60]))
         self.nodes[0].running = False
 
         self.log.info("Start bitcoin with -version for version information")
         self.nodes[0].start(extra_args=['-version'],
                             stderr=subprocess.PIPE, stdout=subprocess.PIPE)
         # Node should exit immediately and output version to stdout.
         ret_code = self.nodes[0].process.wait(timeout=1)
         assert_equal(ret_code, 0)
         output = self.nodes[0].process.stdout.read()
         assert b'version' in output
         self.log.info("Version text received: {} (...)".format(output[0:60]))
+
+        # Test that arguments not in the help results in an error
+        self.log.info(
+            "Start bitcoind with -fakearg to make sure it does not start")
+        self.nodes[0].start(extra_args=['-fakearg'],
+                            stderr=subprocess.PIPE, stdout=subprocess.PIPE)
+        # Node should exit immediately and output an error to stderr
+        ret_code = self.nodes[0].process.wait(timeout=1)
+        assert_equal(ret_code, 1)
+        output = self.nodes[0].process.stderr.read()
+        assert b'Error parsing command line arguments' in output
+        self.log.info("Error message received: {} (...)".format(output[0:60]))
+
         # Clean up TestNode state
         self.nodes[0].running = False
         self.nodes[0].process = None
         self.nodes[0].rpc_connected = False
         self.nodes[0].rpc = None
 
 
 if __name__ == '__main__':
     HelpTest().main()
diff --git a/test/lint/check-doc.py b/test/lint/check-doc.py
index a4e0107a6..6b257336f 100755
--- a/test/lint/check-doc.py
+++ b/test/lint/check-doc.py
@@ -1,89 +1,70 @@
 #!/usr/bin/env python3
 # Copyright (c) 2015-2016 The Bitcoin Core developers
 # Copyright (c) 2019 The Bitcoin developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 '''
 This checks if all command line args are documented.
 Return value is 0 to indicate no error.
 
 Author: @MarcoFalke
 '''
 
 from subprocess import check_output
 from pprint import PrettyPrinter
 import glob
 import re
 
 TOP_LEVEL = 'git rev-parse --show-toplevel'
 FOLDER_SRC = '/src/**/'
 FOLDER_TEST = '/src/**/test/'
 
 EXTENSIONS = ["*.c", "*.h", "*.cpp", "*.cc", "*.hpp"]
 REGEX_ARG = r'(?:ForceSet|SoftSet|Get|Is)(?:Bool)?Args?(?:Set)?\(\s*"(-[^"]+)"'
 REGEX_DOC = r'AddArg\(\s*"(-[^"=]+?)(?:=|")'
 
-# list unsupported, deprecated and duplicate args as they need no documentation
-SET_DOC_OPTIONAL = set(['-benchmark',
-                        '-blockminsize',
-                        '-dbcrashratio',
-                        '-debugnet',
-                        '-forcecompactdb',
-                        # TODO remove after the Nov 2019 upgrade
-                        '-gravitonactivationtime',
-                        '-h',
-                        '-help',
-                        '-parkdeepreorg',
-                        '-replayprotectionactivationtime',
-                        '-rpcssl',
-                        '-socks',
-                        '-tor',
-                        '-usehd',
-                        '-whitelistalwaysrelay'])
-
 # list false positive unknows arguments
 SET_FALSE_POSITIVE_UNKNOWNS = set(['-zmqpubhashblock',
                                    '-zmqpubhashtx',
                                    '-zmqpubrawblock',
                                    '-zmqpubrawtx'])
 
 
 def main():
     top_level = check_output(TOP_LEVEL, shell=True,
                              universal_newlines=True).strip()
     source_files = []
     test_files = []
 
     for extension in EXTENSIONS:
         source_files += glob.glob(top_level +
                                   FOLDER_SRC + extension, recursive=True)
         test_files += glob.glob(top_level + FOLDER_TEST +
                                 extension, recursive=True)
 
     files = set(source_files) - set(test_files)
 
     args_used = set()
     args_docd = set()
     for file in files:
         with open(file, 'r') as f:
             content = f.read()
             args_used |= set(re.findall(re.compile(REGEX_ARG), content))
             args_docd |= set(re.findall(re.compile(REGEX_DOC), content))
 
     args_used |= SET_FALSE_POSITIVE_UNKNOWNS
-    args_need_doc = args_used - args_docd - SET_DOC_OPTIONAL
+    args_need_doc = args_used - args_docd
     args_unknown = args_docd - args_used
 
     pp = PrettyPrinter()
     print("Args used        : {}".format(len(args_used)))
     print("Args documented  : {}".format(len(args_docd)))
-    print("Args undocumented: {} ({} don't need documentation)".format(
-        len(args_need_doc), len(SET_DOC_OPTIONAL)))
+    print("Args undocumented: {}".format(len(args_need_doc)))
     pp.pprint(args_need_doc)
     print("Args unknown     : {}".format(len(args_unknown)))
     pp.pprint(args_unknown)
 
 
 if __name__ == "__main__":
     main()