Getting Values From Lua

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Return values from dostring

Question: How can I get the return value of the Lua chunk executed by lua_dostring from the C side, i.e. like getting the result returned by the Lua dostring function?

(lhf) Just like the return values of any function. Here is an example:

lua_State *L=lua_open(0);

printf( "%d\n", lua_gettop(L) );

lua_dostring(L, "return 1,'a'" );

printf( "%d\n", lua_gettop(L) );

printf( "%s\n", lua_tostring(L,-2) );

printf( "%s\n", lua_tostring(L,-1) );

returnone.c:

#include <lua.h>

#include <lualib.h>



int main()

{

  lua_State *L=lua_open();

  printf( "%d\n", lua_gettop(L) );

  lua_dostring(L, "return 1,'a'" );

  printf( "%d\n", lua_gettop(L) );

  printf( "%s\n", lua_tostring(L,-2) );

  printf( "%s\n", lua_tostring(L,-1) );

  return 0;

}

Build:

gcc -o returnone returnone.c -I/usr/include/lua50 -llua50 -llualib50

Run: # ./returnone

0

2

1

a

lua_dostring() no longer exists:

returnone.c:

#include <lua.h>

#include <lualib.h>

#include <lauxlib.h>



int main()

{

   lua_State *L = luaL_newstate();

   char buff[] = "return 1,'a'";

   int error;

   printf( "%d\n", lua_gettop(L) );

   error = luaL_loadbuffer(L, buff, strlen(buff), "my test") || lua_pcall(L, 0, LUA_MULTRET, 0);

   if (error) {

      fprintf(stderr, "%s", lua_tostring(L, -1));

      lua_pop(L, 1);  /* pop error message from the stack */

   }

   printf( "%d\n", lua_gettop(L) );

   printf( "%s\n", lua_tostring(L,-2) );

   printf( "%s\n", lua_tostring(L,-1) );

   return 0;

}