Updated compilation instructions

Author: cpp-tutor

README.md

@@ -1,31 +1,52 @@
 # learnmoderncpp-tutorial
 
-Complete, working programs from the C++ tutorial hosted at https://learnmoderncpp.com/course-details/
+Complete, working programs from the C++ tutorial hosted at:
+
+https://learnmoderncpp.com/course-details/
 
 ## Usage
 
-The "headers" directory contains C++ programs with legacy header `#includes`,
-whilst the "modules" directory contains the same programs but using the `import` keyword instead.
+The "headers" subdirectory contains C++ programs with legacy header `#includes`, whilst the "modules" subdirectory contains the same programs but using the `import` keyword instead. See https://learnmoderncpp.com/2020/09/05/where-are-c-modules/ for more details about C++ compilers which have support for modules.
+
+## Compiling under Windows
 
 All programs compile successfully under Windows with Visual Studio 2019 (v16.8 or later).
 
 The supplied batch scripts `build-vs2019-headers.bat` and
-`build-vs2019-modules.bat` can be used to compile all of the programs within a Visual Studio command prompt terminal; simply run:
-"C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars32.bat"
-or similar in a command window, or create a desktop link.
+`build-vs2019-modules.bat` can be used to compile all of the programs within a Visual Studio command prompt, simply run:
+
+```C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars32.bat```
+
+or similar in a command window, or create a desktop link, and then run either of the build scripts.
+
+Alternatively, to compile individual programs from within a Visual Studio command prompt run either (modules):
+
+```
+cl /EHsc /std:c++latest /experimental:moodule /MD 00-example.cpp
+```
 
-To compile individual programs under Linux, use:
+or (headers):
 
 ```
-g++ -std=c++20 -o prog prog.cpp # (for the headers versions)
+cl /EHsc /std:c++latest 00-example.cpp
 ```
 
-or
+substituting the correct file for `00-example.cpp` in either case.
+
+## Compiling under Linux
+
+To compile individual programs in the "headers" subdirectory under Linux, use:
+
 ```
-clang++ -std=c++20 -o prog prog.cpp # (again for the headers versions)
+g++ -std=c++20 -o 00-example 00-example.cpp
 ```
 
-Alternatively, run the supplied shell scripts which are supplied in both the "headers" and "modules" subdirectories.
+or:
+
+```
+clang++ -std=c++20 -o 00-example 00-example.cpp
+```
 
-**Contact:** cpptutor@outlook.com
+substituting both occurrencies of `00-example` with the correct file name.
 
+Alternatively, run one of the supplied shell scripts `build-gcc-headers.sh` or `build-clang-headers.sh` which are supplied in the "headers" subdirectory, or `build-clang-modules.sh` found in the "modules" subdirectory. (The last of these needs to change `import std.core;` to `import std;` for each source file before compilation, using the `sed` utility.)