Source files
------------

We build all the tools into a single virt-mem executable, in order to
share the most runtime.  Almost all the code between individual tools
is shared anyway.

lib/

 - The common core of all the tools.  Library, kernel symbols, command
   line handling, memory images, etc.

   lib/virt_mem.ml contains most of the important 'glue' code.

uname/
dmesg/
  etc.

 - The code specific to each tool.  This is usually rather small because
   the code in lib/ does the hard work.

mem/

 - This brings everything together and links it into a single executable.
   Other than that purpose, there is almost nothing in this directory.

General structure of lib/virt_mem.ml
------------------------------------

We start with a bare kernel memory image ('Virt_mem_types.image0')
which gets successively enhanced with extra data along the way:

	Parse command line arguments,
	work out what virtual machines to
	process, load kernel images

		|
		|	(passes a 'Virt_mem_types.image0')
		V

	Find kernel symbols

		|
		|	(enhanced into a 'Virt_mem_types.image1')
		V

	Find kernel version (uname)

		|
		|	(enhanced into a 'Virt_mem_types.image2')
		V

	Call tool's "run" function.

Tools can register other callbacks which get called at earlier stages.