Add source code for examples

[bkmgit]

Problem

The examples are nice, but need to be retyped by hand and could also serve as tests for implementations.

Proposal

Have source code for the examples and then extract a code fragment that appears in the book.

Changes to the Text

An extra script will be required to extract the portion of the programs to be included in the text. A program style guide will also be needed.

Impact on Implementations

The examples can serve as additional tests for implementations.

Impact on Users

It will make it easier for users to learn MPI

References

A variant of this technique has been used well in https://www.pbrt.org/

[wgropp]

Note that we already have tools that extract the examples and can add the "missing" information, as part of the tool that confirms that the examples do, in fact, at least compile. We should start there.

[wesbland]

@wgropp Is this something that can be automated with our makefiles so we could dump it on the website?

[wgropp]

Not all examples are worth extracting, and they would clutter up the web site. I didn't find a good example of publishing extracted code at www.pbrt.org - there, the code is in github.
A relatively easy option is to add an option to the example extractor that would help name the file for an example and keep a list, so that they could be copied to the website. Before doing that, we should decide how these would be presented on the web site, and how we decide which were worth extracting.

[wgropp]

This can be done at any time - we don't need to tie this to any particular MPI release.