c++ - How I get the cdata out in c function with variable arguments using luajit? -

here code. aim print messages. in printc, e...but arrives cdata. how can unpack or circumvent that?

extern "c" {     static int printc ( lua_state *l )     {            // not work cdata         //executor* e = ( executor* ) lual_checkudata(l, 1, "cdata"); n             //lual_checkudata(l, 1, "void *");           if ( e->writelog )         {             int no = lua_gettop ( l ) ;              ( int = 2; <= no; i++ )             {                 cout << lua_tostring (l,i);             }           }         return 1;     }  } 

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// initialised lua_pushcfunction ( l, printc ); lua_setglobal ( l, "printc" ); lua_pushinteger ( l, ( long ) ); // in class executor lua_setglobal ( l, "p" ); 

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p= ffi.cast("void *",p) function   print()    return  printc(p) end 

you can't. lua c api , luajit ffi deliberately separated , cannot interact.

rewrite printc in lua using ffi, or write lua c api bindings library you're using p with. i.e. use 1 or other.