Re: C calls Lua or Lua calls C?

[Philippe Lhoste <PhiLho@...>]

On 20/01/2011 05:02, Steve Litt wrote:
> In general, when game programmers use C and Lua, to they fire up a C program
> that calls a Lua script, or do they fire up a Lua script that calls a C
> program, or are both commonly done?

Actually, when you "fire up a Lua script", you run a C program first! It is the first and 
primary application using Lua, the Lua command line interface calling the Lua interpreter.

> I'm glad you responded. In my research I've found no examples of how to start
> in Lua and load C modules, nor any documentation of same. Do you know of a
> trivial "hello world" application of calling C from Lua for Lua 5.1?

Two ways:
- just recompile the interpreter with your C module, exposing it as as some library (look 
at I/O module, for example);
- or make a dynamic library to be used with 'require'.

The first one is used by applications scripted with Lua (games, editors...); the second 
one is used when you want to use the Lua language (interpreter with command line handling) 
with some added facilities (filesystem, sockets, etc.).

--
Philippe Lhoste
--  (near) Paris -- France
--  http://Phi.Lho.free.fr
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