留念，第一次在C中调用lua成功！

反反复复学lua N多次了，这次终于在C中调用lua成功了！一大进步啊！

记录下过程：

1、找到代码如下：

//add.c

#include <stdio.h>

#include "lua.h"

#include "lualib.h"

#include "lauxlib.h"

/*the lua interpreter*/

lua_State* L;

int

luaadd(int x, int y)

{

int sum;

/*the function name*/

lua_getglobal(L,"add");

/*the first argument*/

lua_pushnumber(L, x);

/*the second argument*/

lua_pushnumber(L, y);

/*call the function with 2 arguments, return 1 result.*/

lua_call(L, 2, 1);

/*get the result.*/

sum = (int)lua_tonumber(L, -1);

/*cleanup the return*/

lua_pop(L,1);

return sum;

}

int

main(int argc, char *argv[])

{

int sum;

/*initialize Lua*/

L = lua_open();

/*load Lua base libraries*/

luaL_openlibs(L);

/*load the script*/

luaL_dofile(L, "add.lua");

/*call the add function*/

sum = luaadd(10, 15);

/*print the result*/

printf("The sum is %d \n",sum);

/*cleanup Lua*/

lua_close(L);

return 0;

}

然后，lua.add的代码如下

--add two numbers

function add(x,y)

return x + y

end

然后，尝试编译：gcc -o add add.c

提示： fatal error: lua.h: No such file or directory

然后，locate lua.h，无果。。。

原来在ubuntu下lua的安装包，binary和dev是分开装的，找了一下，需要安装另外一个包liblua5.1-dev

唔，装好了还是需要用-I指定，所以先找下lua.h被放哪里的。

sudo updatedb

locate lua.h

显示的结果：

/home/zxluo/Documents/backup/Work/luascript/AndroLua/jni/lua/lua.h

/usr/include/lua5.1/lua.h

/usr/include/lua5.1/lua.hpp

/usr/src/linux-headers-3.2.0-23-generic/include/config/scsi/dh/alua.h

/usr/src/linux-headers-3.2.0-24-generic/include/config/scsi/dh/alua.h

所以，添加文件再次编译：gcc -o add add.c -I /usr/include/lua5.1/

出现提示：

/tmp/ccPtEQyI.o: In function `luaadd':

main.c:(.text+0x23): undefined reference to `lua_getfield'

main.c:(.text+0x37): undefined reference to `lua_pushnumber'

main.c:(.text+0x4b): undefined reference to `lua_pushnumber'

main.c:(.text+0x64): undefined reference to `lua_call'

main.c:(.text+0x78): undefined reference to `lua_tonumber'

main.c:(.text+0x93): undefined reference to `lua_settop'

/tmp/ccPtEQyI.o: In function `main':

main.c:(.text+0xac): undefined reference to `luaL_newstate'

main.c:(.text+0xc2): undefined reference to `luaL_openlibs'

main.c:(.text+0xd6): undefined reference to `luaL_loadfile'

main.c:(.text+0xf8): undefined reference to `lua_pcall'

main.c:(.text+0x133): undefined reference to `lua_close'

collect2: ld returned 1 exit status

那个啥，是没有把库link过来，gcc不知道要把这些函数ld到哪里去，继续找liblua：

locate liblua

打印结果：

/usr/lib/x86_64-linux-gnu/liblua5.1-c++.a

/usr/lib/x86_64-linux-gnu/liblua5.1-c++.so

/usr/lib/x86_64-linux-gnu/liblua5.1-c++.so.0

/usr/lib/x86_64-linux-gnu/liblua5.1-c++.so.0.0.0

/usr/lib/x86_64-linux-gnu/liblua5.1.a

/usr/lib/x86_64-linux-gnu/liblua5.1.so

/usr/lib/x86_64-linux-gnu/liblua5.1.so.0

/usr/lib/x86_64-linux-gnu/liblua5.1.so.0.0.0

所以添加编译选项：gcc -o add main.c -I /usr/include/lua5.1 -llua5.1

哦也～这下没有错误了

你可以改动add.lua试试，比如在x+y后面再+10! 啊哈， what happened?

amazing script!