>>246
こんな感じでもOK

#include <lua.h>
#include <lauxlib.h>
#include <lualib.h>
int main(int argc, char **argv) {
  int i;
  lua_State *L, *co;
  L = lua_open();
  lua_baselibopen(L);
  lua_dofile(L, "test.lua");
  co = lua_newthread(L);
  lua_getglobal(co, "co_func");
  for (i = 0; i < 4; i++) {
lua_pushnumber(co, i);
    printf("c: resume=%d\n", lua_resume(co, 1));
    printf("c: co result1=%lf\n", lua_tonumber(co, -2));
    printf("c: co result2=%lf\n", lua_tonumber(co, -1));
  }
  lua_close(L);
  return 0;
}