关于select socket error 10022

最新推荐文章于 2024-01-14 01:34:46 发布

徐新华

最新推荐文章于 2024-01-14 01:34:46 发布

阅读量6.7k

点赞数

CC 4.0 BY-SA版权

文章标签： socket null struct server

本文链接：https://blog.youkuaiyun.com/xuxinhua/article/details/7531695

本文分析了使用select函数时出现的超时错误原因，并提供了一种修正方案，确保在超时情况下程序能正确处理文件描述符集合。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

看下面代码是否有问题：

struct timeval time;
time.tv_sec = 0;
time.tv_usec = 1000;

for(;;)
{
if(g_bServerStart == false)
goto cleanup;

retval = select(0, &readfds, NULL, NULL, &time);
//retval = select(0, &readfds, NULL, NULL, NULL);
if (retval == SOCKET_ERROR)
{
fprintf(stderr, "ob select failed %d\n", WSAGetLastError());
goto cleanup;
}

if(retval == 0)
continue;

}

select会出现超时后错误，原因为select后，超时，会清除FDSET即没有响应的描述符，导致readfds失效。正确的写法为

struct timeval time;
time.tv_sec = 0;
time.tv_usec = 1000;

for(;;)
{
if(g_bServerStart == false)
goto cleanup;

//
// The fd sets should be zeroed out before using them to prevent errors.
FD_ZERO(&readfds);

// Set the server sockets
FD_SET(g_ob_server_socket, &readfds);

retval = select(0, &readfds, NULL, NULL, &time);
//retval = select(0, &readfds, NULL, NULL, NULL);
if (retval == SOCKET_ERROR)
{
fprintf(stderr, "ob select failed %d\n", WSAGetLastError());
goto cleanup;
}

if(retval == 0)
continue;