register_lua_function.c

const char* TABLE_NAME = "functions";
const char* FUNCTION_NAME = "my_lua_function";

int my_lua_function(lua_State* L);

lua_State* L;

/* Assuming that the table exists already */

/* Get the table */
lua_getglobal(L, TABLE_NAME);

/* Push the function name */
lua_pushstring(L, FUNCTION_NAME);

/* Register the function */
lua_pushcfunction(L, my_lua_function);

/* Assign the function to the table */
lua_settable(L, -3);

/* Remove the table from the stack (i.e. ensure that the stack is like before registering the function) */
lua_pop(L, 1);