Lua 调用自定义C模块

#include <math.h>
#include <lua5.2/lua.h>
#include <lua5.2/lauxlib.h>
#include <lua5.2/lualib.h>

static int hello_sin(lua_State *L){
    double d = luaL_checknumber(L, 1);
    lua_pushnumber(L, sin(d));
    return 1;
}

static const struct luaL_Reg hello_lib[] = {
    {"hello_sin" , hello_sin},
    {NULL, NULL}
};

int luaopen_hello_lib(lua_State *L){
    luaL_newlib(L, hello_lib);
    //luaL_register(L, "hello_lib",hello_lib); // lua 5.1
    return 1;
}

local hello = require "hello_lib"
print(hello.hello_sin(1))