下面的代码用来实现,异步方式监听9000端口,然后接收客户端数据包。
碰到一个奇怪的问题:客户端第一次连接,能正常接收数据,后面就接收不到数据。但是客户端是在一直发包,并且用Sniffer抓包发现,客户端数据包也正常发过来的。//main
int main(int argc, char* argv[])
{
BOOL bRet = myInitSocket();
if (bRet == FALSE)
{
return 0;
}SOCKET fd;
bRet = myBindSocket(9000, fd); //监听9002
if (bRet == FALSE)
{
return 0;
}bRet = myListen(fd, MAX_CONNECTION); //允许同时20个客户端连接
if (bRet == FALSE)
{
return 0;
}//客户端IP和端口
SOCKET sockRemote;
SOCKADDR_IN addrRemote;int recvLen = 0;
int selectResult = 0;
int sendLen = 0;
char buf[1024] = {0};timeval TimeOut;
TimeOut.tv_sec = 0;
TimeOut.tv_usec = 500;//==========
int i, rc;
int max_fd, tmp_fd;
int fd_array[20];
fd_set read_fd, all_fd;
memset(&fd_array, -1, FD_NUM); //初始化Socket组
fd_array[0] = fd;
max_fd = fd;
//==========while (TRUE)
{
read_fd = all_fd; //Socket集合
FD_ZERO(&all_fd);
FD_SET(fd, &all_fd); if(select(max_fd + 1, &read_fd, NULL, NULL, &TimeOut) == -1)
{
continue;
} //接受客户端连接
//客户端第一次连接时,FD_ISSET返回非0
//但是之后就一直返回0 !!!!!!
if(FD_ISSET(fd, &read_fd))
{
printf("accept...");
int addrLen = sizeof(addrRemote);
if((tmp_fd = accept(fd, (SOCKADDR*)&addrRemote, &addrLen)) == -1)
{
printf("accept fail\n");
continue;
}
else
{
printf("accept ok\n");
for(i = 0; i < FD_NUM; i++)
{
if(fd_array[i] == -1)
{
fd_array[i] = tmp_fd; //保存句柄
break;
}
}
//FD_ZERO(&all_fd);
FD_SET(tmp_fd, &all_fd);
if(tmp_fd > max_fd)
{
max_fd = tmp_fd; //更新max_fd
}
}
continue;
}
else
{
//printf("FD_ISSET fd fail\n");
} //接收数据
for(i = 0; i < FD_NUM; i++)
{
if(FD_ISSET(fd_array[i], &read_fd)) //查询Socket
{
rc = recv(fd_array[i], buf, BUF_SIZE, 0);
if(rc <= 0)
{
printf("recv<0 \n");
}
else
{
buf[rc] = '\0';
printf("recv:%s\n", buf);
}
//break;
}
else
{
//printf("FD_ISSET fd_array fail\n");
}
} Sleep(1);
}system("pause");
return 0;
}
碰到一个奇怪的问题:客户端第一次连接,能正常接收数据,后面就接收不到数据。但是客户端是在一直发包,并且用Sniffer抓包发现,客户端数据包也正常发过来的。//main
int main(int argc, char* argv[])
{
BOOL bRet = myInitSocket();
if (bRet == FALSE)
{
return 0;
}SOCKET fd;
bRet = myBindSocket(9000, fd); //监听9002
if (bRet == FALSE)
{
return 0;
}bRet = myListen(fd, MAX_CONNECTION); //允许同时20个客户端连接
if (bRet == FALSE)
{
return 0;
}//客户端IP和端口
SOCKET sockRemote;
SOCKADDR_IN addrRemote;int recvLen = 0;
int selectResult = 0;
int sendLen = 0;
char buf[1024] = {0};timeval TimeOut;
TimeOut.tv_sec = 0;
TimeOut.tv_usec = 500;//==========
int i, rc;
int max_fd, tmp_fd;
int fd_array[20];
fd_set read_fd, all_fd;
memset(&fd_array, -1, FD_NUM); //初始化Socket组
fd_array[0] = fd;
max_fd = fd;
//==========while (TRUE)
{
read_fd = all_fd; //Socket集合
FD_ZERO(&all_fd);
FD_SET(fd, &all_fd); if(select(max_fd + 1, &read_fd, NULL, NULL, &TimeOut) == -1)
{
continue;
} //接受客户端连接
//客户端第一次连接时,FD_ISSET返回非0
//但是之后就一直返回0 !!!!!!
if(FD_ISSET(fd, &read_fd))
{
printf("accept...");
int addrLen = sizeof(addrRemote);
if((tmp_fd = accept(fd, (SOCKADDR*)&addrRemote, &addrLen)) == -1)
{
printf("accept fail\n");
continue;
}
else
{
printf("accept ok\n");
for(i = 0; i < FD_NUM; i++)
{
if(fd_array[i] == -1)
{
fd_array[i] = tmp_fd; //保存句柄
break;
}
}
//FD_ZERO(&all_fd);
FD_SET(tmp_fd, &all_fd);
if(tmp_fd > max_fd)
{
max_fd = tmp_fd; //更新max_fd
}
}
continue;
}
else
{
//printf("FD_ISSET fd fail\n");
} //接收数据
for(i = 0; i < FD_NUM; i++)
{
if(FD_ISSET(fd_array[i], &read_fd)) //查询Socket
{
rc = recv(fd_array[i], buf, BUF_SIZE, 0);
if(rc <= 0)
{
printf("recv<0 \n");
}
else
{
buf[rc] = '\0';
printf("recv:%s\n", buf);
}
//break;
}
else
{
//printf("FD_ISSET fd_array fail\n");
}
} Sleep(1);
}system("pause");
return 0;
}
if(FD_ISSET(fd, &read_fd))
{
printf("accept...");
int addrLen = sizeof(addrRemote);
if((tmp_fd = accept(fd, (SOCKADDR*)&addrRemote, &addrLen)) == -1)
{
printf("accept fail\n");
continue;
}
else
{
printf("accept ok\n");
for(i = 0; i < FD_NUM; i++)
{
if(fd_array[i] == -1)
{
fd_array[i] = tmp_fd; //保存句柄
break;
}
}
//FD_ZERO(&all_fd);
FD_SET(tmp_fd, &all_fd);
if(tmp_fd > max_fd)
{
max_fd = tmp_fd; //更新max_fd
}
}
continue;
}
else
{
//printf("FD_ISSET fd fail\n");
}
虽然没有调试,但是我觉得有数据到来了应该是执行这一段,然后调用了accept阻塞了。你可以自己调试一下看看是不是这么回事。