//////////////////////////////////////////////////////////////////////
                               rvs 0.6.1
	retroactive versioning system
	          a versioning system that allows you to check
	            in commit 2 before commit 1
//////////////////////////////////////////////////////////////////////

                              hacking

   There are two main parts to rvs, the wrapper, and the core.  The
   wrapper is a small executable, located in the PATH, and is the one
   called when you type `rvs'.  The core is a set of many small
   executables that do all the real work.

  build system

   The build system rvs uses is rather simple.
   `./configure' does two things:
   	* create a preprocessor (`tmp/var.sed')
   	* run `Makefile.orig' through the preprocessor to generate a
   	  propper `Makefile'
   Then, the Makefile runs each file in `source/' through the
   preprocessor, and writes the resulting files to `out/'.

   preprocessor

    The preprocessor contains all configuration variables.  When it
    processes a file every instance of `$$VAR_NAME$$' is replaced by
    that variable's value. Note that this replacement only happens for
    defined variables.

  configuration Variables

   Again the configuration variables and their default values are:
   	VER   	'0.6.1'
   	SHELL 	'/usr/bin/env bash'
   	prefix	"$HOME"
   	bindir	'bin'
   	libdir	'/etc/rvs/'

   The wrapper is installed at `$$prefix$$/$$bindir$$/rvs'
   The  core   is installed at `$$libdir$$/'
   The source for the wrapper is in `source/rvs'
   The source for the  core   is in `source/rvs-core/'

    $$SHELL$$ is the shell all shell scripts that are part of rvs are
    run in.  As of rvs 0.6.1 all executables are shell scripts. 

   Most of these can easily be changed _after_ compilation also:
   	VER  	line 4 of the wrapper
   	SHELL	line 1 each shell script
   	prefix	simply move the wrapper
   	bindir	simply move the wrapper
   	libdir	move the core, then update the line `RVSDIR=...' in
   	      	the wrapper
   
   I have designed this system to be extremely modular. As you may
   have figured out, each bit on functionality is in it's own
   executable, and the file you call when you type `rvs' is just a
   wrapper for them.

----------------------------------------------------------------------
----- The rest is copy/pasted, and still needs to be copy-edited.-----
----------------------------------------------------------------------

   commit actually does take a parameter. It can commit any file or
   directory. It works as it does because if no file is given, it
   defaults to ./. If it is given a directory (as it is by
   default), it loops through each file in the directory and
   commits them (by calling itself). In order to actually commit a
   file or directory it calls rvs commit.type where type is the
   standard unix file-type code:

   block       (buffered) special b 
   character (unbuffered) special c 
   directory                      d 
   named pipe (FIFO)              p 
   regular file                   f 
   symbolic link                  l 
   socket                         s 
   door (Solaris only)            D 

   As you probably noticed, only directories and regular files have
   been implemented in this release. get works in much the same
   way. If you implement any other file types, save the commit and
   get functions accordingly, and uncomment the line in
   source/rvs-corecommit. Any commit function takes a filename as
   an argument and outputs the according commit id to stdout. Any
   get function takes the commit id as an argument and uses stdout
   only if verbose, or to report errors. So the modules communicate
   via pipes, which is generally considered bad-design, and
   libraries should be used. I deliberatly broke this because this
   way:

    1. incompatible licences can be used for different modules
    2. modules can be added/removed on the fly
    3. one can use any lanugage to write new modules, without
       having to worry about bindings

  known bugs

	* borks on files with the newline character. The smart thing
	  to do would be to escape all speacial characters.
	  Files to be changed:
	  	* source/rvs-core/commit
	  	* source/rvs-core/commit.d
	  	* source/rvs-core/get.d

   I have set up bazaar repository at Launchpad:
   	https://launchpad.net/rvs
   Only until rvs becomes self-hosting.

   If anyone needs any help, let me know.

~ Luke Shumaker <LukeShu@sbcglobal.net>
Happy Hacking!