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Hi Steve!

On 1/20/11 5:02 AM, Steve Litt wrote:
I'm glad you responded. In my research I've found no examples of how to start in Lua and load C modules
trivial "hello world" application of calling C from Lua for Lua 5.1?

Here is a static Lua-C Hello World Sample / Tutorial.

This links a C extension statically into Lua. It's the other option you have, beside dynamic linking, that ties your extension in as closely as the Lua standard libs that need no require() call to be available, and thus no pathes. The modification of linit.c does the loading.

At the end there's how you integrate it into the official Lua Makefile. That's the one in the src folder, not the one in ../src.

File ../src/hello.lua:

File src/hello.c:
#include <stdio.h>
#include "lauxlib.h"

static int hello(lua_State *L) {
    printf("Hello World!\n");
    return 1;

static const struct luaL_Reg hellolib [] = {
    { "hello", hello }, /* registering the function */
    { NULL, NULL }

LUALIB_API int luaopen_hellolib (lua_State *L) {
    luaL_register(L, "hellolib", hellolib); /* registering the module */
    return 1;

File src/hello.h:
#include "lua.h"

#define HELLO_LIBNAME    "hellolib"
LUALIB_API int (luaopen_hellolib) (lua_State *L);

Extend file src/linit.c:
#include "lauxlib.h"
#include "hello.h" /* add */
static const luaL_Reg lualibs[] = {
  {"hellolib", luaopen_hellolib}, /* add */

Extend src/Makefile:
LIB_O=    lauxlib.o lbaselib.o ldblib.o liolib.o lmathlib.o loslib.o ltablib.o \
    lstrlib.o loadlib.o linit.o hello.o # add
hello.o: hello.c # add

# (end of Makefile)

Build & Run
Build Lua from ../src/ folder, e.g. sudo make

Run src/lua hello.lua