--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/StdInCommand.h	Sat Jul 28 22:29:40 2018 +0200
@@ -0,0 +1,89 @@
+#pragma once
+
+#include <cstdlib>
+#include <iostream>
+#include <string>
+#include <vector>
+#include <algorithm>
+#include <string>
+
+#include <typedefs.h>
+#include <locale>
+
+#include "Command.h"
+#include "CLI.h"
+#include "RelpipeCLIException.h"
+
+namespace relpipe {
+namespace in {
+namespace cli {
+
+/**
+ * TODO: consider code merge with ArgumentsCommand
+ */
+class StdInCommand : public Command {
+private:
+	wstring_convert<codecvt_utf8<wchar_t>> convertor; // TODO: support also other encodings.
+
+	/**
+	 * Reads next value from arguments and (if no arguments left) from input
+	 * @param input
+	 * @param arguments
+	 * @param i current index in the arguments vector
+	 * @param required if true, exception is thrown when no data found
+	 * @return 
+	 */
+	relpipe::writer::string_t readNext(std::istream& input, const std::vector<relpipe::writer::string_t>& arguments, size_t& i, relpipe::writer::boolean_t required) {
+		using namespace relpipe::writer;
+		using namespace relpipe::cli;
+
+		if (i < arguments.size()) {
+			return arguments[i++];
+		} else {
+			std::stringstream value;
+
+			while (true) {
+				char ch;
+				input.get(ch);
+				if (ch == 0 || input.eof() || input.fail()) break;
+				else value << ch;
+			}
+
+			return convertor.from_bytes(value.str());
+		}
+	}
+
+
+public:
+
+	void process(std::istream& input, std::ostream& output, const relpipe::writer::string_t& command, const std::vector<relpipe::writer::string_t>& arguments) override {
+		using namespace relpipe::writer;
+
+		size_t i = 0;
+		string_t relationName = readNext(input, arguments, i, true);
+		integer_t attributeCount = std::stoul(readNext(input, arguments, i, true)); // TODO: use integer data type's method?
+		boolean_t writeHeader = true; // TODO: add option for header omitting
+
+		std::shared_ptr<RelationalWriter> writer(Factory::create(output));
+
+		std::vector<std::pair<string_t, TypeId >> attributes(attributeCount);
+
+		for (size_t j = 0; j < attributeCount; j++) {
+			string_t attributeName = readNext(input, arguments, i, true);
+			TypeId attributeType = writer->toTypeId(readNext(input, arguments, i, true));
+			attributes[j] = {attributeName, attributeType};
+		}
+
+		writer->startRelation(relationName, attributes, writeHeader);
+
+		while (true) {
+			string_t value = readNext(input, arguments, i, false);
+			if (value.empty() && (input.eof() || input.fail())) break;
+			else writer->writeAttribute(value);
+		}
+	}
+};
+
+}
+}
+}

--- a/nbproject/configurations.xml	Sat Jul 28 15:42:42 2018 +0200
+++ b/nbproject/configurations.xml	Sat Jul 28 22:29:40 2018 +0200
@@ -9,6 +9,7 @@
       <itemPath>Command.h</itemPath>
       <itemPath>DemoCommand.h</itemPath>
       <itemPath>RelpipeCLIException.h</itemPath>
+      <itemPath>StdInCommand.h</itemPath>
     </logicalFolder>
     <logicalFolder name="ResourceFiles"
                    displayName="Resource Files"
@@ -66,6 +67,8 @@
       </item>
       <item path="RelpipeCLIException.h" ex="false" tool="3" flavor2="0">
       </item>
+      <item path="StdInCommand.h" ex="false" tool="3" flavor2="0">
+      </item>
       <item path="relpipe-in-cli.cpp" ex="false" tool="1" flavor2="0">
       </item>
     </conf>
@@ -105,6 +108,8 @@
       </item>
       <item path="RelpipeCLIException.h" ex="false" tool="3" flavor2="0">
       </item>
+      <item path="StdInCommand.h" ex="false" tool="3" flavor2="0">
+      </item>
       <item path="relpipe-in-cli.cpp" ex="false" tool="1" flavor2="0">
       </item>
     </conf>

--- a/relpipe-in-cli.cpp	Sat Jul 28 15:42:42 2018 +0200
+++ b/relpipe-in-cli.cpp	Sat Jul 28 22:29:40 2018 +0200
@@ -11,14 +11,18 @@
 #include "Command.h"
 #include "ArgumentsCommand.h"
 #include "DemoCommand.h"
+#include "StdInCommand.h"
 
 using namespace relpipe::cli;
 using namespace relpipe::in::cli;
 using namespace relpipe::writer;
 
 Command* findCommand(string_t commandName) {
+	// TODO: better command names
+	// TODO: help command
 	if (commandName == L"demo") return new DemoCommand();
 	else if (commandName == L"generate") return new ArgumentsCommand();
+	else if (commandName == L"generate-from-stdin") return new StdInCommand();
 	else throw RelpipeCLIException(L"Unknown command: " + commandName, CLI::EXIT_CODE_UNKNOWN_COMMAND);
 }