diff --git a/src/util/system.cpp b/src/util/system.cpp
index b8aa168082be5..c7e342a59e6dd 100644
--- a/src/util/system.cpp
+++ b/src/util/system.cpp
@@ -373,6 +373,7 @@ bool ArgsManager::ParseParameters(int argc, const char* const argv[], std::strin
 
     for (int i = 1; i < argc; i++) {
         std::string key(argv[i]);
+        if (key == "-") break; //bitcoin-tx using stdin
         std::string val;
         size_t is_index = key.find('=');
         if (is_index != std::string::npos) {
@@ -392,15 +393,13 @@ bool ArgsManager::ParseParameters(int argc, const char* const argv[], std::strin
         if (key.length() > 1 && key[1] == '-')
             key.erase(0, 1);
 
-        // Check that the arg is known
-        if (!(IsSwitchChar(key[0]) && key.size() == 1)) {
-            if (!IsArgKnown(key)) {
-                error = strprintf("Invalid parameter %s", key.c_str());
-                return false;
-            }
+        const unsigned int flags = FlagsOfKnownArg(key);
+        if (flags) {
+            InterpretOption(key, val, m_override_args);
+        } else {
+            error = strprintf("Invalid parameter %s", key.c_str());
+            return false;
         }
-
-        InterpretOption(key, val, m_override_args);
     }
 
     // we do not allow -includeconf from command line, so we clear it here
@@ -416,7 +415,7 @@ bool ArgsManager::ParseParameters(int argc, const char* const argv[], std::strin
     return true;
 }
 
-bool ArgsManager::IsArgKnown(const std::string& key) const
+unsigned int ArgsManager::FlagsOfKnownArg(const std::string& key) const
 {
     assert(key[0] == '-');
 
@@ -434,9 +433,12 @@ bool ArgsManager::IsArgKnown(const std::string& key) const
 
     LOCK(cs_args);
     for (const auto& arg_map : m_available_args) {
-        if (arg_map.second.count(base_arg_name)) return true;
+        const auto search = arg_map.second.find(base_arg_name);
+        if (search != arg_map.second.end()) {
+            return search->second.m_flags;
+        }
     }
-    return false;
+    return ArgsManager::NONE;
 }
 
 std::vector<std::string> ArgsManager::GetArgs(const std::string& strArg) const
@@ -835,18 +837,17 @@ bool ArgsManager::ReadConfigStream(std::istream& stream, const std::string& file
     }
     for (const std::pair<std::string, std::string>& option : options) {
         const std::string strKey = std::string("-") + option.first;
-        // Check that the arg is known
-        if (!IsArgKnown(strKey)) {
-            if (!ignore_invalid_keys) {
+        const unsigned int flags = FlagsOfKnownArg(strKey);
+        if (flags) {
+            InterpretOption(strKey, option.second, m_config_args);
+        } else {
+            if (ignore_invalid_keys) {
+                LogPrintf("Ignoring unknown configuration value %s\n", option.first);
+            } else {
                 error = strprintf("Invalid configuration value %s", option.first.c_str());
                 return false;
-            } else {
-                LogPrintf("Ignoring unknown configuration value %s\n", option.first);
-                continue;
             }
         }
-
-        InterpretOption(strKey, option.second, m_config_args);
     }
     return true;
 }
diff --git a/src/util/system.h b/src/util/system.h
index 9f8d94f5209ea..75e80968262d1 100644
--- a/src/util/system.h
+++ b/src/util/system.h
@@ -293,9 +293,10 @@ class ArgsManager
     std::string GetHelpMessage() const;
 
     /**
-     * Check whether we know of this arg
+     * Return Flags for known arg.
+     * Return ArgsManager::NONE for unknown arg.
      */
-    bool IsArgKnown(const std::string& key) const;
+    unsigned int FlagsOfKnownArg(const std::string& key) const;
 };
 
 extern ArgsManager gArgs;