RRDLua is a Lua module for RRD functions.

- Configuration

  From the top dir of RRDtool package, run "./configure", or
  "./configure --enable-lua-site-install" if you prefer to install in
  Lua's search path.

 You should have lua 5.0, or superior, and respective lua-dev packages
 installed before executing configure.

- Compilation and installation

 Run 'make' and 'sudo make install'. If you don't enable lua-site-install,
 the Lua modules will be installed together with RRDtool, under the subdir
 <INSTALL_PREFIX>lib/lua/<lua_version>.

- Testing

 Install RRDtool first, as above. Then, enter the bindings/lua dir, run
 'make test' and use your preferred viewer to display the just created
 'test.png'. If you can read "Enjoy Lua RRDtool module!" on the picture,
 everything went fine.

- Using with Lua 5.1

 Start your programs with:

  ------..-----------------------------------------------------------
  package.cpath = '<INSTALL_PREFIX/lib/lua/5.1/?.so;' ..
                  package.cpath
  require 'rrd'
  -------------------------------------------------------------------

 OBS: If you use the option --enable-lua-site-install you won't need
      to change package.cpath like above. 

- Using with Lua 5.0

 The Lua binding for RRDtool needs the compat-5.1 module to work with
 Lua 5.0. Some Linux distros, like Ubuntu gutsy and hardy, have it
 already integrated in Lua 5.0 -dev packages, so you just have to
 require:

  require 'compat-5.1'

 For other platforms, the compat-5.1 module that comes with this Lua
 binding will be installed for you in the same dir where RRDtool was
 installed, under the subdir .../lib/lua/5.0. In this case, you must
 tell your Lua programs where to find it by changing the Lua var
 LUA_PATH:

  --- compat-5.1.lua is only necessary for Lua 5.0 ------------------
  original_LUA_PATH = LUA_PATH
  -- try only compat-5.1 installed with RRDtool package
  LUA_PATH = '<INSTALL_PREFIX>/lib/lua/5.0/?.lua'
  require 'compat-5.1'
  LUA_PATH = original_LUA_PATH
  original_LUA_PATH = nil
  --- end of code to require compat-5.1 -----------------------------

  Now we can require the rrd module just like we did for 5.1 above:

  -------------------------------------------------------------------
  package.cpath = '<INSTALL_PREFIX>/lib/lua/5.0/?.so;' ..
                  package.cpath
  require 'rrd'
  -------------------------------------------------------------------
