Improve documentation

src/app/cmdoptions.cpp

@@ -1,7 +1,17 @@
 ///
 /// @file   cmdoptions.cpp
-/// @brief  Parse command-line options for the primesieve console
-///         (terminal) application.
+/// @brief  Command-line option handling for the primesieve
+///         command-line application. The command-line options are
+///         first parsed in cmdoptions.cpp and stored in a CmdOptions
+///         object. Afterwards we execute the function corresponding
+///         to the user's command-line options in the main() function
+///         in main.cpp.
+///
+///         How to add a new command-line option:
+///
+///         1) Add a new option enum in cmdoptions.h.
+///         2) Add your option to parseOptions() in cmdoptions.cpp.
+///         3) Add your option to main() in main.cpp.
 ///
 /// Copyright (C) 2024 Kim Walisch, <[email protected]>
 ///

src/app/main.cpp

@@ -1,6 +1,17 @@
 ///
 /// @file   main.cpp
-/// @brief  primesieve console application.
+/// @brief  Command-line option handling for the primesieve
+///         command-line application. The command-line options are
+///         first parsed in cmdoptions.cpp and stored in a CmdOptions
+///         object. Afterwards we execute the function corresponding
+///         to the user's command-line options in the main() function
+///         in main.cpp.
+///
+///         How to add a new command-line option:
+///
+///         1) Add a new option enum in cmdoptions.h.
+///         2) Add your option to parseOptions() in cmdoptions.cpp.
+///         3) Add your option to main() in main.cpp.
 ///
 /// Copyright (C) 2024 Kim Walisch, <[email protected]>
 ///