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+# Adding a Version Number and Configured Header File #
+
+The first feature we will add is to provide our executable and project with a
+version number. While we could do this exclusively in the source code, using
+CMakeLists provides more flexibility.
+
+To add a version number we modify the CMakeLists file as follows:
+
+ cmake_minimum_required(VERSION 3.3)
+ project(Tutorial)
+
+ # the version number.
+ set(Tutorial_VERSION_MAJOR 1)
+ set(Tutorial_VERSION_MINOR 0)
+
+ # configure a header file to pass some of the CMake settings
+ # to the source code
+ configure_file(
+ "${PROJECT_SOURCE_DIR}/TutorialConfig.h.in"
+ "${PROJECT_BINARY_DIR}/TutorialConfig.h"
+ )
+
+ # add the executable
+ add_executable(Tutorial tutorial.cxx)
+
+ # add the binary tree to the search path for include files
+ # so that we will find TutorialConfig.h
+ target_include_directories(Tutorial PUBLIC
+ "${PROJECT_BINARY_DIR}"
+ )
+
+
+We then create a TutorialConfig.h.in file in the source tree with the
+following contents:
+
+ // the configured options and settings for Tutorial
+ #define Tutorial_VERSION_MAJOR @Tutorial_VERSION_MAJOR@
+ #define Tutorial_VERSION_MINOR @Tutorial_VERSION_MINOR@
+
+When CMake configures this header file the values for @Tutorial_VERSION_MAJOR@
+and @Tutorial_VERSION_MINOR@ will be replaced by the values from the CMakeLists
+file. Next we modify tutorial.cxx to include the configured header file and to
+make use of the version numbers. The resulting source code is listed below.
+
+ // A simple program that computes the square root of a number
+ #include <cmath>
+ #include <iostream>
+ #include <string>
+ #include <sstream>
+
+ #include "TutorialConfig.h"
+
+ int main (int argc, char *argv[])
+ {
+ if (argc < 2) {
+ std::cout << argv[0] << " Version "
+ << Tutorial_VERSION_MAJOR << "." << Tutorial_VERSION_MINOR
+ << std::endl;
+ std::cout << "Usage: " << argv[0] << " number" << std::endl;
+ return 1;
+ }
+
+ double inputValue = atof(argv[1]);
+
+ double outputValue = sqrt(inputValue);
+ std::cout << "The square root of "
+ << inputValue << " is " << outputValue << std::endl;
+ return 0;
+ }
+
+# Adding C++11 support #
+
+Let's add some C++11 features to our project. We will need to explicitly state
+in the CMake code that it should use the correct flags. The easiest way to
+enable C++11 support for CMake is by using the CMAKE_CXX_STANDARD
+and CMAKE_CXX_STANDARD_REQUIRED variables.
+
+First, replace `atof` with `std::stod` in tutorial.cxx.
+
+Then, add the CMAKE_CXX_STANDARD and CMAKE_CXX_STANDARD_REQUIRED variables to
+the CMakeLists file. The STANADARD value should be set to 11, and REQUIRED
+should be set to True.
+
+
+# Build and Test #
+
+Run cmake or cmake-gui to configure the project and then build it with your
+chosen build tool
+
+cd to the directory where Tutorial was built (likely the make directory or
+a Debug or Release build configuration subdirectory) and run these commands:
+
+ Tutorial 4294967296
+ Tutorial 10
+ Tutorial