SDL和X11多线程致命IO错误

SDL and X11 multithreading Fatal IO Error

本文关键字：IO 错误 多线程 X11 SDL      更新时间：2023-10-16

我正在尝试使用C++和SDL创建一个简单的多线程示例，如下所示：

#include <iostream>
#include "SDL/SDL_image.h"
#include "SDL/SDL.h"
#include "SDL/SDL_thread.h"
#include "X11/Xlib.h"
#include "SDLAbstractionLayer.h"
#include <string>
using namespace std;
SDL_Thread* thread = NULL;
bool quit = false;
int myThread(void* data) {
   while (!quit) {
      //caption animation
      SDL_WM_SetCaption ("Thread is running", NULL);
      SDL_Delay(250);
      SDL_WM_SetCaption("Thread is running.", NULL);
      SDL_Delay(250);
      SDL_WM_SetCaption("Thread is running..", NULL);
      SDL_Delay(250);
      SDL_WM_SetCaption("Thread is running...", NULL);
      SDL_Delay(250);
   }
   return 0;
}
int main(int argc, char* argv[]) {
   SDL_Surface* screen = init(640, 480, "");
   XInitThreads();
   Surface test("resources/image.png");
   thread = SDL_CreateThread(myThread, NULL);
   SDL_Event event;
   while (!quit) {
      if(SDL_PollEvent(&event)) {
         if (event.type == SDL_QUIT) {
            quit = true;
            break;
         }
         fillScreen(screen, Surface::WHITE);
         applySurface(0, 0, test, screen);
         flip(screen);
      }
   }
   cleanUp();
   SDL_KillThread(thread);
   return 0;
}

问题是，当我在Eclipse或终端中运行它时，我会得到以下消息：

XIO:  fatal IO error 0 (Success) on X server ":0.0"
  after 113 requests (113 known processed) with 0 events remaining.

或者这个：

XIO:  fatal IO error 11 (Resource temporarily unavailable) on X server ":0.0"
  after 113 requests (113 known processed) with 2 events remaining.

我正在使用带有Eclipse开普勒的Ubuntu 13。我试着做了一些研究，但没能找到任何有用的东西。

编辑：所以我更新了代码，包括一个计数器和一些到处都是的cout：

int myThread(void* data) {
   while (!quit) {
      //caption animation
      SDL_WM_SetCaption ("Thread is running", NULL);
      SDL_Delay(250);
      cout << "Thread is running 1" << endl;
      SDL_WM_SetCaption("Thread is running.", NULL);
      SDL_Delay(250);
      cout << "Thread is running 2" << endl;
      SDL_WM_SetCaption("Thread is running..", NULL);
      SDL_Delay(250);
      cout << "Thread is running 3" << endl;
      SDL_WM_SetCaption("Thread is running...", NULL);
      SDL_Delay(250);
      cout << "Thread is running 4" << endl;
   }
   return 0;
}
int main(int argc, char* argv[]) {
   SDL_Surface* screen = init(640, 480, "");
   XInitThreads();
   Surface test("resources/image.png");
   thread = SDL_CreateThread(myThread, NULL);
   SDL_Event event;
   int count = 1;
   while (!quit) {
      if(SDL_PollEvent(&event)) {
         if (event.type == SDL_QUIT) {
            quit = true;
            break;
         }
         fillScreen(screen, Surface::WHITE);
         applySurface(0, 0, test, screen);
         flip(screen);
         cout << "finished iteration " << count++ << endl;
      }
   }

下面是控制台运行一次后的输出：

finished iteration 1
Thread is running 1
XIO:  fatal IO error 0 (Success) on X server ":0.0"
      after 113 requests (113 known processed) with 0 events remaining.

然后，在第二次运行后：

finished iteration 1
finished iteration 2
Thread is running 1
Thread is running 2
XIO:  fatal IO error 0 (Success) on X server ":0.0"
      after 116 requests (116 known processed) with 0 events remaining.

如果有疑问，请在主线程上执行所有SDL操作。

主要异常是SDL_PostEvent()。

没关系。我刚刚收到了一封发给制作教程的人的电子邮件的回复，我正在关注：

是的，这是我的应用程序中的错误，我正在SDL2.0教程中修复它。查看SDL2.0多线程示例以获得修复。问题是SDL多个线程执行渲染不起作用。因此，从另一个线程设置标题工作不正常。在2.0教程中，渲染是在一个线程和控制台输出中进行的在另一个中。

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