how to remove a value from the globals table

["Zé Pedro" <zarroba@...>]

I've seen a similar question already answered in the list but I'm not sure it applies to my problem.
In my program I'm executing lua code made by users and I have no control over it. What I'm doing now is setting the variables the code needs by doing:
                     lua_pushinteger(pLuaState, (int)atoi(value.c_str()));
                     lua_setglobal(pLuaState, name.c_str());

and then executing the script doing:
                     luaL_dostring (pLuaState, 
script.c_str())

the thing is that the script has no functions or anything, just calls to methods and declaration of variables. Once a script is executed the variables should be cleared but this must be made in C after the luaL_dostring call. Is there any way to do this or do I have to create a new LuaState for each time I execute a script?

thanks,
José Tavares

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