Function costatus

lua/lbaselib.c:498–515

    {"running", "suspended", "normal", "dead"};

static int costatus (lua_State *L, lua_State *co) {
  if (L == co) return CO_RUN;
  switch (lua_status(co)) {
    case LUA_YIELD:
      return CO_SUS;
    case 0: {
      lua_Debug ar;
      if (lua_getstack(co, 0, &ar) > 0)  /* does it have frames? */
        return CO_NOR;  /* it is running */
      else if (lua_gettop(co) == 0)
          return CO_DEAD;
      else
        return CO_SUS;  /* initial state */
    }
    default:  /* some error occured */
      return CO_DEAD;
  }
}


static int luaB_costatus (lua_State *L) {